Archive through October 17, 2010

 

New member
Username: Panzer6

Post Number: 1
Registered: Aug-10
One thing that happens when you biwire your loudspeakers is that the input of the high- and the low-pass filters are fed with different input signals. The difference is a result of the high frequencies and the low frequencies being forced to travel different paths, perhaps through different types of cables, but under all circumstances through cables who have seen different loads (a tweeter with a high pass filter has a completely different impedance response compared to a woofer with a low pass filter!).

What happens is that the drivers will work less good together than when their filter halves were fed with equal signals. The result is a generation of more static and stochastic phase error sounds at different directions from the loudspeaker. The stochastic phase error sounds appear because there may be different types of unlinearities in the low- and high-frequency paths.

What does this sound like? Well, usually, just as you may expect from physics, it appears as a change in the reproduction of space and sound stage. Often, the first impression is that the "biwired" sound presents extended "dimensions", more "air", and is more "living". The impression after a week or month, however, is that all recordings sound very much alike, and the "airiness" appears on all records. It does not even sound like air anymore, instead more like a slime that pollutes every record you play. No wonder, since it is not a real, recorded quality but a "speaker characteristic" added to all reproduced material. "Sameness" is another word for it.
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15091
Registered: May-04
.

"One thing that happens when you biwire your loudspeakers is that the input of the high- and the low-pass filters are fed with different input signals."

This is incorrect. The only way to achieve discrete outputs (not inputs) from a single source is to enlist an active filter in front of the amplifiers. With this active device in the signal chain you can get closer to (but still not achieve absolutely) discrete output to the individual drivers. Simple biwiring takes the same full range signal from the same single (channel) output of a single amplifier and does nothing more at this point in the game than (hopefully) feed discrete sections of the passive crossover employed in the multi-way speaker system and (once again, hopefully) allow a discrete return path for the back electromotive force generated by the driver to the point where both halves once again join at a single input to the amplifier and it's NFB circuit. However, biwiring is not a proven tactic in anyway and for multiple reasons. The most obvious reason I would hope is that manufacturers understand marketing a product to an unwitting and uninformed/misinformed public and the engineering department understands the cost involved in actually making the marketing/sales department's touted "marketable" advances fully operable.


"The difference is a result of the high frequencies and the low frequencies being forced to travel different paths, perhaps through different types of cables ... "

This too is incorrect. A biwired cable is carrying full range information up to the point where it meets a (hopefully) discrete passive filter within the speaker system. It is only after this filter that any division of duties will occur and that then involves the internal cabling within the speaker but not the cable feeding the full range singal from the single amplifier channel to the speaker.


" ... under all circumstances through cables who have seen different loads (a tweeter with a high pass filter has a completely different impedance response compared to a woofer with a low pass filter!)."


This is never stated as a goal or a benefit of biwiring since "impedance" is seldom the single factor which affects amplifier performance if you assume you are dealing with a well designed and well executed amplifier. Since the amplifier has only a single output to the speaker and a single return leg input from the speaker, the total impedance of the speaker system remains the same in either biwired or mono-wired configuartions. If the cable you are using has so much "impedance" as to be a factor, you really should be assuming the cable is acting as a passive tone control and not the biwiring itself.


"What happens is that the drivers will work less good together than when their filter halves were fed with equal signals."


That makes no sense. The drivers are discrete passive devices which cannot judge how
"good together" they operate.


"The result is a generation of more static and stochastic phase error sounds at different directions from the loudspeaker. The stochastic phase error sounds appear because there may be different types of unlinearities in the low- and high-frequency paths."


At best, that's linguistic mumbo-jumbo which means nothing. "Unlinearities" in not a word so there's not much to make of that other than you don't understand what you are posting.

From there you venture further and further into the weeds. Deeper and deeper you go until you are finally lost to all humanity, never to be heard from again.


Or, at best, let's hope for that.


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Gold Member
Username: Dmitchell

Ottawa, Ontario Canada

Post Number: 4123
Registered: Feb-07
I've for the life of me never understood how bi-wiring can make any difference whatsoever. Even tried it a few times... nada.
 

Gold Member
Username: Magfan

USA

Post Number: 1427
Registered: Oct-07
Yet, a lot of bi-wire capable speakers make a big deal of the jumper.
And with my panels, the 'remove the fuse' school gets good play.
 

Gold Member
Username: Dmitchell

Ottawa, Ontario Canada

Post Number: 4178
Registered: Feb-07
I do believe in replacing the cheap, thin brass jumper plates that come with most speakers, but I usually just use a small length of speaker cable.
 

Platinum Member
Username: Nuck

Post Number: 15307
Registered: Dec-04
Somehow I think that the issue is not at rest...
 

Platinum Member
Username: Artk

Albany, Oregon USA

Post Number: 13042
Registered: Feb-05
Biwiring has made a considerable difference for me on several speakers. Paradigm, Totem, Wharfdeale to mention but a few. Some designers don't like and don't include that capability in their designs, John DeVore being one.
 

Platinum Member
Username: Nuck

Post Number: 15312
Registered: Dec-04
John already did the work for you, Art, not like the Ikea solution.
I like stuff like that.
Having a speaker that can be made active easily is the next step for fiddling.
 

Platinum Member
Username: Artk

Albany, Oregon USA

Post Number: 13044
Registered: Feb-05
Yep...Mr DeVore is one clever fella and I love them apes!
 

Platinum Member
Username: Nuck

Post Number: 15321
Registered: Dec-04
No options here neither, Art.
And I love what they do.
 

Platinum Member
Username: Glasswolf

Post Number: 13878
Registered: Dec-03
Bi-wiring binding posts on speakers are really only beneficial at all (and even here it's debatable) if you're using a set of 4 monoblock amplifiers to drive 1 pair of speakers, allowing one amplifier to drive the low frequency, and one to drive the mid/high range per speaker. If you use one amp with two channels to drive that bi-amped speaker, you're most likely still sharing the same amplifier power supply and not really achieving any benefit. In car audio we amplify the mids/highs with a separate amp from the lows to avoid the lows drawing enough current to wash out the front stage, which happens due to a number of factors, but in a home audio system on city-supplied AC current with a dedicated high-current circuit for the amplifier(s) this really should be a concern one would think.
 

Platinum Member
Username: Nuck

Post Number: 15424
Registered: Dec-04
Multi-amping (mono amping) drivers is fine, but powering the passive crossovers would normally be addressed before this point, with actives.
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15286
Registered: May-04
.

What you're describing, GlassWolf, is not biwiring but bi-amping - which a a completely different approach. There's no need for monoblock amplifiers.

"If you use one amp with two channels to drive that bi-amped speaker, you're most likely still sharing the same amplifier power supply and not really achieving any benefit."

Well, one amp with two channels is a stereo amp. If you connect the two channels of a stereo amp to drive individual drivers in one cabinet you're going to porbably) have the left/right channel coming from the woofer and the opposite channel coming from the tweeter. That would risk damage to the amp by possibly having both channels connected together through the crossover. You're going to have to split your outputs of your pre amp to do otherwise and then have two amplifier channels which can be devoted to driving each section of a single speaker and you really want to make certain you have totally discrete crossover sections.

But that still is not biwiring.


" ... but in a home audio system on city-supplied AC current with a dedicated high-current circuit for the amplifier(s) this really should be a concern one would think."


I don't know what you mean here. You don't need a dedicated circuit to biwire a speaker.


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Gold Member
Username: Dmitchell

Ottawa, Ontario Canada

Post Number: 4303
Registered: Feb-07
I thought we had put this to rest ;-)
 

Platinum Member
Username: Glasswolf

Post Number: 13880
Registered: Dec-03
I said I was talking about bi-amping, Jan. I was describing the only useful reason for having bi-wire posts on a pair of speakers. Using 4 ends at the speaker and 2 ends at the amp is completely pointless, as already noted.
The reason for bi-amping speakers is to separate the signal path beyond the pre-amp to get full, dedicated power to each speaker range in the cabinet (LF and HF) so yes, having monoblock amplification is beneficial, even if the two isolated amplifiers are in one casing, as many are, using a "stereo amp" with a common power supply is somewhat self-defeating. The reason I mentioned the dedicated circuit is because most high power amplifiers recommend one. This holds especially true for Class-A amplifiers, and when using multiple amplifiers. Most 15A home circuits aren't really designed to supply the current these amplifers will demand, particularly when 2 or 3 rooms may be sharing that same circuit.
If the crossover is properly wired, there should be no shared signal path between the HP and LP sides of a bi-wired set of speaker terminals. There certainly aren't in my MartinLogans, or any of my KEFs. I'm driving my KEF center channel (bi-amped) with an Adcom GFA-545 Mk II now without any issue at all, using left channel for LP, and right channel for HP. Checking for any signal path commonality is as simple as using a continuity tester at the speaker terminals, but that is a good point as something to check before doing this sort of wiring, I agree.

Anyway, long story short, my point was to the remark about why speakers even offer bi-wire posts, and not to obfuscate the pointlessness of bi-wiring versus bi-amplification. Yes, I was talking about bi-amping because that's the only real reason to have bi-wire posts on speakers. Bi-wiring alone (8 terminals speaker-side) with a stereo amplifier (4 terminals amp-side) is of course useless. The OP is a troll, which sadly nobody picked up on to this point, for some reason. "1" total post on a new account, and all he did was post a few paragraphs of total dysinformation to stir up trouble. I wasn't looking to start a whole new debate. I was just sharing my thoughts on how bi-wire posts could possibly have a use.
 

Platinum Member
Username: Glasswolf

Post Number: 13881
Registered: Dec-03
Here's an interesting article I just read.. thought I'd share it, for what it's worth.
http://sound.westhost.com/bi-amp.htm#bi_wiring
 

Platinum Member
Username: Plymouth

Canada

Post Number: 14963
Registered: Jan-08
I agree with Glasswolf!

Bi-wiring give nothing on a strereo amplifier, the speaker with bi-wirings are made for 2 amplifiers and give nothing more for only one, if you use cheap wire maybe you will see a difference but with good one none.
 

Platinum Member
Username: Artk

Albany, Oregon USA

Post Number: 13270
Registered: Feb-05
You both are wrong.

Pick up a set of any well made and well designed speaker with facility for biwiring. Leave the jumpers in and try single wiring to the LF drivers first...then switch to the HF drivers. You will hear a difference and that should tell you all you need to know relative to biwiring.
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15288
Registered: May-04
.

IMO large amounts of useful and accurate information cn be found on Elliott's site, however, you have to keep in mind he is an engineer first and foremost and engineers don't always have the same perspective on certain aspects of consumer audio as do the end users. Elliott, by his own admission, hasn't tried biwiring and, even if he had, the variances in speakers which do and do not benefit from such "tweaks" would necessitate experimenting with more than two or three pairs of speakers.



Glasswolf, what you were describing amounts to bi-amping but I am not certain you made that clear in your initial post.




"The reason for bi-amping speakers is to separate the signal path beyond the pre-amp to get full, dedicated power to each speaker range in the cabinet (LF and HF) ... "


Possibly this is a reason given in the car stereo world but this is not the reason for doing bi-amping in the home audio world. High frequency material uses so little actual "power" in comparison to low frequencies that a ten watt amplifier would likely be adequate for the vast majority of "audiophile" type high frequency speakers. Very few "high end" tweeters require anything more than minimal amperage. Therefore, "getting full, dedicated power" to each driver is hardly prevented by the demands of high frequency music material.

At normal listening levels even the most difficult home speakers typically cruise along at less than twenty watts total (and often far, far less than that amount), most of which will be required by the lowest frequency driver while the tweeter is being fed less than 1/10 of a watt. You have to understand that (the average) audiophile type home audio system is not based upon contests to see which system plays the loudest. If that is you're goal in home audio, neither buying lots o'watts nor more amplifiers will be the quickest route to a trophy or a complaint from your neighbors.


" I was describing the only useful reason for having bi-wire posts on a pair of speakers. Using 4 ends at the speaker and 2 ends at the amp is completely pointless, as already noted."


Quite a few speaker designers and numerous users would certainly disagree with your determination that biwiring is "completely pointless". Biwiring can and does serve a beneficial function in many speakers. We have discussed this on numerous occasions here on this forum along with a quite lengthy thread that ran a few years back. There are serious misunderstandings by many users regarding biwiring but there are also more than a few on this forum who feel it is beneficial in their personal system(s).


" ... having monoblock amplification is beneficial, even if the two isolated amplifiers are in one casing, as many are, using a "stereo amp" with a common power supply is somewhat self-defeating."



"Self-defeating"?!!! While I won't argue with the benefits of discrete power supplies from the raw AC input forward, I'm afraid you're going to find most home audio amplifiers do share one common power supply. My recollection is your Adcom is one of the many amps with one common transformer/power supply. Actually, it's rather difficult finding a home amp with true dual power supplies.


"The reason I mentioned the dedicated circuit is because most high power amplifiers recommend one. This holds especially true for Class-A amplifiers, and when using multiple amplifiers. Most 15A home circuits aren't really designed to supply the current these amplifers will demand, particularly when 2 or 3 rooms may be sharing that same circuit."



All 15 amp home circuits are designed (by code) to provide a full 15 amps either on demand at the surge associated with the start up of such things as refrigerators or dishwashers or over a period of time when multiples of such appliances are in constant use. The high current, instantaneous surges associated with refrigerator start up and a clothes washing machine kicking into spin cycle are the sort that cause your lights to dim in the entire house. Not much in home audio is likely to cause your lights to flicker and, if they do, you probably have more serious problems than the lack of a dedicated ciruit to your amplifier. Home audio use seldom if ever requires the time constant involved with such appliances running constantly for 10 minutes or more. Large dynamic musical peaks come and go with the flow of music and therefore do not represent a constant current draw on the circuit nor do they pull the sort of amperage as will a 15 amp motor at start up.

You seem to associate dedicated circuits with "high power" amplifiers. That would be missing the point of a dedicated circuit IMO. Once again we're back to the point of very few home amplifiers actually requiring the time constant current draw which would call for a 20 amp circuit. Fifteen amp curcuits will do fine in all but, say, 1-2% of the highest wattage "audiophile" music systems out there. Installing a 20 amp circuit by no means provides 20 amps when there is no need for such high current flow present in the music. Current is supplied as called for by the system's demands. Therefore, the logic behind dedicated circuits in an "audiophile's" listening room goes beyond simple amperage.

Equally, I can see no association between high current and class A amplifiers. Quite the contrary, most class A consumer amps are lower wattage affairs - due mainly to the inefficiencies (and also the subsequent heat generation) of pure class A operation. In home audio it's once again somewhat difficult to find a true class A amplifier that is rated at more than 50 watts and most fall in the under 25 watt range. Theoretically, the multiple paralleled outputs needed to achieve high wattage in pure class A tends to defeat many of the sonic advantages of true class A operation. Nelson Pass prefers pure class A and his older 200 watt designs for Threshold tended toward reasonably high current capacity though even his most ambitious voltage driven amps of that period are still outdone by numerous high wattage class AB behemoths. (Pass has now moved towards a "current dumping" sort of topology which is meant for difficult loads but even here the addition of 20 amp circuits from the breaker is not generally a necessity.) I'm not understanding your conclusion that class A or even multiple amplifiers will be current starved on a single 15 amp circuit. Neither of those two qualifiers determine the actual current draw from the AC line.

When high current is temporarily demanded by the signal/speaker load the amplifier first draws from its supply reservoir capacitors located in the power supply. This is where current demands are dealt with in all but the most mediocre of amplifiers today. Current draw from the AC outlet occurs only as these caps are drained and, by the nature of capacitors, can only take place at a specific rate. However, the real key to this is the speaker load which will determine how much current is required from the amplifier as it is presented with a signal which fits into the generally rather narrow frequency range where low impedance and high electrical phase angle both occur in the speaker system. Therefore, "on demand" current supply from the AC outlet is; first, unlikely to occur in the average home music system and, second, will come into play only after the amplifier's supply reservoir has been sufficiently drained. Finally, with wise and informed speaker selection high current might never be required of the amplifier.

And none of this has anything to do with dedicated circuits in, say, 98-99% of the home audio systems out there.



"Bi-wiring alone (8 terminals speaker-side) with a stereo amplifier (4 terminals amp-side) is of course useless."


Again I have to disagree. Any amplifier with "A/B" speaker selection will have eight connections per speaker channel and they can easily be used for biwiring. Many members here believe doing so has been beneficial to their system's sound quality. GlassWolf, you haven't disproven the benefits of biwiring, you've simply stated your opinion that there are no benefits. Reality says you are wrong according to many members here and on other such forums.



You will find, GlassWolf, that when you come to home audio from car stereo there are entirely different rules which apply. This is largely due to the different demands placed on the two types of systems. IMO most of what you've learned in car stereo will need to be unlearned to deal well with home equipment.




"The OP is a troll, which sadly nobody picked up on to this point ... "

Not really, this is from my initial post in this thread, "From there you venture further and further into the weeds. Deeper and deeper you go until you are finally lost to all humanity, never to be heard from again.

Or, at best, let's hope for that."






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Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15289
Registered: May-04
.

"Bi-wiring give nothing on a strereo amplifier, the speaker with bi-wirings are made for 2 amplifiers and give nothing more for only one, if you use cheap wire maybe you will see a difference but with good one none."


Try providing actual facts which would support your claims. Saying only that you don't believe is no proof of anything other than your inability to provide facts which back up what you say. I would say you are absolutely wrong on virtually everything you've claimed. Read my repsonse to GlassWolf for many reasons why this is so. "Cheap wire" has nothing to do with the benefits of biwiring and, in fact, biwiring might actually be a benefit to buying cheap wire.


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Gold Member
Username: Gavdawg

Albany, New York

Post Number: 1590
Registered: Nov-06
GW, with decent cable, the difference is more obvious to my ears than with OEM.

And I am not talking about the "speaker hose" crap
 

Platinum Member
Username: Plymouth

Canada

Post Number: 14970
Registered: Jan-08
Hi Jan Vigne!

Happy to talk with you!

So I'm not a car system guy but a HI-fi home audio guy, I'm able to play in car audio but I found that come too much db and it destroy my ears.

At Rotac Electronique the owner tested 3 option, Bi-wiring then Bi-amp on Bi-wiriring and also very good wires on a Bi-wiring speakers.

The best result was Bi-amp(Tube Class A on mid/high then a transistorised amp with heavy duty power supply) which win.

The Bi-wiring is second best then simple wiring in last, he noted that the quality of wiring was much more important on simple wiring and Bi-wiring permit to save on wiring, the impedance and the lenght of wire play in game. His result was a good wire can do then the best is both amplifiers.

The surch of purity tell me that it is the best but the money can be send for other thing to improve the audio system.

Sh1t my speaker wiring cost only 730$!

You will certainly tell me that a tube amplifier sound better than a transistor like I tought before that I modified my Adcom's, I can tell that it is a fashion to heat the room with amplifier.

Best regard!
 

Platinum Member
Username: Plymouth

Canada

Post Number: 14971
Registered: Jan-08
Rotac also tested my modified Adcom then he compared it with a tube amp which cost 15,000$, like I say to GW he listened it 3 hours long then he was very surprise that my Adcom beat this expensive tube amp!

Rotac is the most reputy hi-fi house in Québec city!
 

Platinum Member
Username: Glasswolf

Post Number: 13883
Registered: Dec-03
I was using my Krell KSA-200 as an example, which in the manual states teh need for a dedicated circuit for AC power, as an example, and bi-amplification is very useful for speakers like my MartinLogan ESLs, which really do ahve two discrete portions for HF and LF. That aside, my UPS does go off in a brown out state when that Adcom 555 powers on, since it shares the circuit with my AVR and Television at the moment (soon to be rectified when I do the built-in shelving for the components and use a dedicated filtered circuit for the AV power for 3 amps and an AVR.) I'm aware the Adcom shares a single power supply, however my Aragon 8008BB does not, as another example. I'd have to look again to see if the Krell does or not, I don't really recall off hand.
I have used Transparent and AudioQuest bi-wire cables and despite the impedance differences of which, (yes as an engineer) I'm aware, I don't really haer any audible difference to be honest.
I'm also very aware of power requirements and power to volume ratio figures, but thank you for pointing that out. My Pass F5 and Aleph J and very good examples of just how little power is required to have plenty of output with outstanding audio. I apologize if I was unclear to you in my initial post. I do agree the actual speaker in question will make a large difference as to what any change to the rest of the system will affect.

Oh, and the only reason I'm actually bi-amplifying the center channel is because I wanted to use the GFA-545, as I have teh 555 on my mains, and another 545 on the surround speakers, and this third amp was handy for the center channel but does not support a bridged mode, so it was a simple solution to just run one channel to the LF and one to the HF to utilize the amplifier. It was really more for convenience than for any sort of audible gain.
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15290
Registered: May-04
.

Plymouth, I'm going to guess English is not your primary language. It would be an unusual circumstance where a tailor made system being bi-amped as you describe would not sound "better" than a system simply biwired from either amp. Though what you describe is a faux bi-amped system which still relies on the quality of the OEM crossover for its results. The highest degree of benefits to be gained from bi-amping would come with filters in front of the amplifiers.


"The surch of purity tell me that it is the best but the money can be send for other thing to improve the audio system."

If this is meant to imply there are numerous methods available to modify a system, then, once again, it would be an unusual system that would not fit that criteria. But that has nothing to do with the credibility of biwiring as one of those options.


"You will certainly tell me that a tube amplifier sound better than a transistor like I tought before that I modified my Adcom's ... "


No, I'm not here to tell anyone one thing is better than another. That's not my job - nor is it anyone else's job IMO.

There are two large issues to discuss reagarding your post, Plymouth. First, if you only tried this experiment one, or even two, or even five pairs of speakers, you have not given biwiring a fair chance. Individual speakers respond to biwiring in different ways and many speakers which have the capacity to be biwired - a sufficient number of posts at the speaker - are not truly meant to have any sonic improvement improvements from the extra posts, they are meant only to have higher sales with the extra posts included. Second, you've provided nothing more than subjective impressions of your findings in an uncontrolled experiment. You knew which wiring configuration was being used, no? Such experiments are fraught with preconceived conclusions and are not at all helpful.

I'm not looking for subjective opinions since I can easily find just as many opinions which disagree with your conclusions. A few of these conclusions would have come from better experiments.

Do you have any objective facts or even just well reasoned thoughts on the efficacy of biwiring? If not, then I'll just mark you down as "don't know".


.
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15291
Registered: May-04
.

"I was using my Krell KSA-200 as an example, which in the manual states teh need for a dedicated circuit for AC power ... "


Need? Or "preference"? No one is denying a dedicated circuit should make an audible improvement in the vast majority of high quality systems. But, does Krell actually state the "need" for a dedicated circuit or do they merely suggest you consider such wiring? Is the warranty voided should you not immediately plug the amp into a dedicated circuit?

What does Krell say about 15 vs 20 amp circuits? At which amperage do they rate their OEM power cable? It is indeed the rare bird of an amplifier that comes stock with a 20 amp cable. If the manufacturer supplies a 15 amp cable, then a 20 amp circuit in the wall would tend toward overkill for the sake of overkill. This would especially be true of any system with a power conditioner where the current is going to be choked down by no more than 10-15 watt fusing. If your present UPS is shutting down with the Adcoms, then that UPS certainly would not benefit from a 20 amp circuit breaker.



" have used Transparent and AudioQuest bi-wire cables and despite the impedance differences of which, (yes as an engineer) I'm aware, I don't really haer any audible difference to be honest."


Then as far as objective facts regarding biwiring go, I'll put you down in the same column as Plymouth - "don't know". You tried with what? one pair of speakers? Not, as you had said, "completely pointless", just you don't know the reasons but subjectively you cannot hear any changes on that pair of speakers.



"I apologize if I was unclear to you in my initial post."


I get used to it the more posts you acquire on this side of the forum.



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Platinum Member
Username: Plymouth

Canada

Post Number: 14973
Registered: Jan-08
Jan Vigne

You are right! I'm a French Canadian! Sorry if you has difficuty to understand me!

In fact I agree with you for majority of your comments!

What I can tell is that many Bi-wiring Hi-Fi speaker are not good at all then put the money on better speaker with only simple wiring give best result than bad speaker.

I think that surround system can't beat a good stereo system, I listen classic, Jazz then all style of music.

''don't know''
I'm not here to make war with you, you don't know my experience with sound.

How old are you then which system you use?

I simply asked it to know more on you!


Best regard!
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15292
Registered: May-04
.

I've been around for quite a few years, I'm no spring chicken. My system isn't something I normally discuss on this forum. It has no bearing on whether I am giving correct information. For what it's worth, my system is comprised of components you are unlikly to be familiar with and which I've owned for some time. Many are modified or DIY. There are tubes in the system but also solid state.

I'm not here to make war with anyone either, I just prefer facts when someone states flatly this or that is or isn't "better" than something else. You're welcome to your opinion but that doesn't get us anywhere in understanding what is happening in a subject such as biwiring.

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Gold Member
Username: Magfan

USA

Post Number: 1643
Registered: Oct-07
I don't want to put words in GlassWolfs mouth, but I THINK he meant that class 'a' amps draw current continuously, not like an a/b amp which can draw lots or little power.

I don't know how bad it can get, but a system with lots of tubes can have a decent current overhead, too, based on a couple amps or more of heater current. Good in winter, bad in summer!
 

Platinum Member
Username: Glasswolf

Post Number: 13885
Registered: Dec-03
a direct quote from the manual of my KSA 250
"B. POWER CONSIDERATIONS
The KSA-150 is rated as delivering 150 watts per channel into 8 ohms. The amount of Class A power is adjusted for the finest sonic performance with a minimum of generated heat and energy consumption. The amplifier's maximum power into 8 ohms is 220 watts per channel. The KSA-250 is rated as delivering 250 watts per channel into 8 ohms. The amplifier's maximum power into 8 ohms is 320 watts per channel.
That every Krell product uses Class A circuitry in all gain and supply stages is a foundation of our design philosophy. A second design commitment that relates to amplifiers is that every unit be capable of doubling its output into successively lower impedances. The KSA-150 will deliver 300 watts per channel into 4 ohms, 600 watts per channel into 2 ohms and 1,200 watts per channel into 1 ohm. The KSA-150 is fully capable of driving impedances below 1 ohm. The KSA-250 will deliver 500 watts per channel into 4 ohms, 1,000 watts per channel into 2 ohms and 2,000 watts per channel into 1 ohm. The KSA-250 is capable of driving impedances below 1 ohm. Given the above, the AC power supplied to the amplifier is crucial to getting maximum performance. The KSA-150 will perate at its peak with a dedicated 20- amp line, although this is not a requirement. Additionally, the KSA-150 should only be operated with the power cord supplied with the unit. Use of other power
cords may damage the amplifier and void its warranty. The KSA-250 requires a dedicated 20-amp line. It too, should only be operated with the power cord supplied with the unit.
Please consult Krell or your dealer before using any devices designed to alter or stabilize the AC power for the KSA-150 or KSA-250."

The UPS is on the same house circuit, for my DVR. It is not between the wall outlet and the amplifiers. I simply stated that when the amplifier powers on, the UPS beeps to signal that there is a sag in line voltage on the circuit.

I have used the bi-wire cables on numerous speakers, having been in the audio industry for over 20 years. I have tried them with anything from conventional cabinets and designs to more esoteric speakers like mag-planars and electrostatics. I have taken measurements on the wires with meter and scope and the numbers revealed would show a difference too insignificant for any human ear to detect. Your arguments, while no more objective than the quotes you chose to highlight as subjective, are based on your desire to hear a difference to justify the money spent and from your statements, I've seen no reference to facts or figures either, let alone any actual research on your part.

Failure on y0ur part yet again, like the last time you tried to argue the need for expensive speaker cables without anything to prove an audible difference, yet swearing you're always right and my arguments get picked at yet never disproved by you.

I retract my apology. Apparently, you're just rather stubborn in spite of accuracy or lack thereof on your part. Having re-read my earlier post, I was quite clear. The fault was in your comprehension and reading skills.
 

Gold Member
Username: Magfan

USA

Post Number: 1644
Registered: Oct-07
Glass, do you have a 'kill-a-watt' plug in meter?
Meters like that are cheap....like about 25$ or so. They will also show power factor, which is NOT a trivial concern at outlet limits.
I'd be curious to know how much current your amp draws...just sitting there. If it is fully class 'a', than it'll stay high.
The power line sag? Turn on cap charging, of course.
 

Platinum Member
Username: Plymouth

Canada

Post Number: 14976
Registered: Jan-08
Jan Vigne

My modified Adcom take about 45 seconds to drain the supply if I power it off, this with maximum gain. I know that only put big capacitors doesn't give a good sound but the damping factor (Yes the system which correct a bad power supply) is reduced to nothing. In fact the supply is split in 2 step, the first is the standard board with 2- 6800uf which I added 2 more (one channel) then a 12 gauge solid copper was soldered on the plate board for less impedance loss, 2 Mallory 750, 000uf (each channels)was hooked directly behind the power transistors, The darlinton transistors was able to drain about 75 amps to the speakers, all the cables was replaced with the best of market at this time as well that connectors banana's and RCA's.
This kind of configuration eliminate totally the frequency of 120 hz from the AC.

Now for the speaker wires, the lenght of the wire then the impedance will affect the result between bi-wire or simple, a absolute zero ohms can't doing any difference. the thing is that a wire is not a supra conductor but pure copper without oxygen give a much more result especially if it contain many conductor individually
shielded.
I saw cheap Chinese cable doing much better than Monster cable to 40 times the cost.
I'm able and I have equipment to test all system, like a frequency generator, sonometer, scope but my ears are the best in result, I like when a piano sound like a piano with the depth of the room.
 

Gold Member
Username: Magfan

USA

Post Number: 1646
Registered: Oct-07
I'd love to see speakers after a nice blast of 75 amps.....even at the couple of volts it doubtless sagged to.
 

Platinum Member
Username: Plymouth

Canada

Post Number: 14977
Registered: Jan-08
Glasswolf


A 2000 watts amplifier doesn't drain 2000 watts on the AC but maybe max 1000W, the capacitors give you the power to produce the 2000 watts.
 

Platinum Member
Username: Plymouth

Canada

Post Number: 14978
Registered: Jan-08
Hi leo stierer

The 75 amps is good to keep the control of the speaker added with a perfect power supply=best control=less distorsion> less distorsion=need less damping> less damping=High frequency pur and clean without coloring.

The reason why a tube sound better is the high voltage which pass through a transformer to decrease the voltage then increase the amperage, the power supply section doesn't need to be very strong due to lower amperage required!
The same formula is applies that for the transistor which works on low voltage but which requires a very powerful power supply>>> best control=less distorsion> less distorsion=need less damping> less damping=High frequency pur and clean without coloring.
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15293
Registered: May-04
.

"Having re-read my earlier post, I was quite clear. The fault was in your comprehension and reading skills."


Not that dull saw of a personal attack again!!! I always envision the folks who resort to the blaming-the-reader-attack as standing before their high school English teacher and protesting (constantly), "A 'D'?!!! That's just stupid and it's all because you're stupid and you lack adequate comprehension skills. I know exactly what I meant!"

However, then you post, "Your arguments, while no more objective than the quotes you chose to highlight as subjective, are based on your desire to hear a difference to justify the money spent and from your statements ... ". To that, GW, I say, ""



Apology retraction graciously accepted, GW. You are a reactionary who resorts to ad hominems when challenged to prove your statements. That's now understood and I'll be on alert in the future. You are certainly not the first I've met on this forum who dislikes being asked to provide proof.


"I'm not here to make war with anyone either, I just prefer facts when someone states flatly this or that is or isn't "better" than something else. You're welcome to your opinion but that doesn't get us anywhere in understanding what is happening in a subject such as biwiring."




OK, your amplifier manufacturer suggests a 20 amp dedicated circuit. But that is not how we got into this discussion. It began when you stated, "In car audio we amplify the mids/highs with a separate amp from the lows to avoid the lows drawing enough current to wash out the front stage, which happens due to a number of factors, but in a home audio system on city-supplied AC current with a dedicated high-current circuit for the amplifier(s) this really should be a concern one would think."

And the end result of this is, as I had earlier said, "... none of this has anything to do with dedicated circuits in, say, 98-99% of the home audio systems out there." Nor does it have anything to do with class A amplifiers, nor does it have anything to do with biwiring which is the topic of this thread.


"I have used the bi-wire cables on numerous speakers, having been in the audio industry for over 20 years. I have tried them with anything from conventional cabinets and designs to more esoteric speakers like mag-planars and electrostatics. I have taken measurements on the wires with meter and scope and the numbers revealed would show a difference too insignificant for any human ear to detect."


Have you considered the possibility that, first, you are undertaking an uncontrolled experiment very much like Plymouth's? Maybe you'll tell me you performed DBT's, which are engineers' favorite tactic for shutting down discussion. I don't know, you haven't said how you performed your experiments. But certainly you understand the placebo and "no-cebo" effect, no? If you've already decided how a change is going to come out, then your expectation bias will provide you with that result in the majority of cases. If you've measured this and that and found no difference you can identify, then you are likely to have an expectation bias which informs you there will be no difference in sound quality. As I've told many people who claim this or that change is "completely pointless", I am not responsible for what you cannot hear. Other listeners whom I respect just as much as you, GW, have claimed to hear significant improvements when moving to biwiring. That you have been unable to detect any improvement does not negate their findings.

Secondly, have you considered that possibly you have yet to find a speaker that would benefit from biwiring because you've tried the "wrong" speakers? This has little to nothing to do with the audiophile bona fides of a speaker. High end speaker designers disagree about the real world benefits of biwiring. If the crossovers in the speakers you've experimented with have discrete ground paths, then it is unlikely those speakers will respond to biwiring. This ground plane sharing, which is common in many speakers of various price ranges, is the most significant issue biwiring attempts to address. Any speaker which is designed for bi-amping (probably) would not respond to biwiring though the opposite is not true. Maybe you just need to try more speakers? I don't know, you haven't said.

Next, you say you've measured the wires. Have you considered you possibly are not looking in the right place? How do you know what you are measuring has anything to do with the effects of biwiring? Have you read any of the actual arguments for biwiring as made by someone other than an informal listener on a forum? If you are "measuring" the cables, then I would say you are not even close to understanding how biwiring can affect a system's performance. While cables can affect sound quality, the issues biwiring seeks to address are most often to be found elsewhere. If you've measured crossovers and found no commonalities at the "-" terminals, then you are still not looking in the right place for how biwiring works (though a thorough visual inspection would be recommended with most boards).

I must conclude, GW, that you simply haven't looked in the right places for the real causes of the problems biwiring addresses. Having looked in the wrong place and found nothing you've made up your mind there is nothing to be found and your negative expectations have been rewarded with failure to perceive any improvements. All of this is a very typical chain of events for an engineer. At this point you conclude you're right - as you knew you would be - and you no longer ask questions at which point you cease to think. This is quite typical of most engineers, wouldn't you say?


" ... you tried to argue the need for expensive speaker cables without anything to prove an audible difference ... "

" ... based on your desire to hear a difference to justify the money spent ... "



You're relatively new to the home audio side of the forums, GW, but anyone who has spent time here will tell you you have this quite wrong. I haven't spent great sums of money on my cables - though I've tried many - and my general policy on this forum is not to recommend anything in the way of product or to claim what I have perceived is anything more than my personal perception of the events. I don't know where you came up with such a criticism of me but I would very much like to see a link to those posts which you feel prove your assertions. Beyond that, I'll just put this down to another tired ol'ad hominem in the same vein as "you lack comprehension skills".


" I've seen no reference to facts or figures either, let alone any actual research on your part."


I've discussed biwring numerous times on this forum. As I've said there was a quite lenghty thread a few years back which went through the research I have performed. I'll put it this way, GW, I was not the person who resurrected what was at the time a stagnating, worthless thread just to state biwiring is "completely pointless". Which, IMO, is a complete slap in the face to those forum members who find biwiring beneficial. My feeling is the person who makes such claims should be the first to provide proof of their statements. Once you've done that, then I will refute or agree with what you've proposed. You say you've taken measurements of the cables and I have now said you're looking in the wrong place. See how that works?

As to objective statements regarding the value of biwiring, I would return you to my first post in this thread where I stated, "Simple biwiring takes the same full range signal from the same single (channel) output of a single amplifier and does nothing more at this point in the game than (hopefully) feed discrete sections of the passive crossover employed in the multi-way speaker system and (once again, hopefully) allow a discrete return path for the back electromotive force generated by the driver to the point where both halves once again join at a single input to the amplifier and it's NFB circuit. However, biwiring is not a proven tactic in anyway and for multiple reasons."

I assume you missed that.

That is a very generic explanation of how biwiring might benefit a speaker system/amplifier circuit. Most people begin looking only at a single part of the system and do not bother to put together all of the pieces as a working system, such an examination would include amplifier, cables and complete speaker systems with their individual components. For more objective information regarding my statements about this topic I would refer you to the "Speakers" section of this forum and go back a few years in time in the archives. The thread was quite lengthy and I addressed quite a few of the common misconceptions regarding biwiring. I even used Elliott as a reference in a few cases.

I really don't feel it's my obligation to repeat this stuff every few months as the topic arises. You've made the definitive statement, GW, that biwiring is "completely pointless". It is now up to you to prove that statement with objective facts as your subjective opinions have been countered and met by other subjective opinions which are in disagreement with your findings. If you have objective facts or research, please introduce them now. Otherwise, we are no further along than we were before you reinvigorated this sad topic.



.
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15294
Registered: May-04
.

"Now for the speaker wires, the lenght of the wire then the impedance will affect the result between bi-wire or simple, a absolute zero ohms can't doing any difference. the thing is that a wire is not a supra conductor but pure copper without oxygen give a much more result especially if it contain many conductor individually
shielded.
I saw cheap Chinese cable doing much better than Monster cable to 40 times the cost.
I'm able and I have equipment to test all system, like a frequency generator, sonometer, scope but my ears are the best in result, I like when a piano sound like a piano with the depth of the room."




"Now for the speaker wires, the lenght of the wire then the impedance will affect the result between bi-wire or simple ... "


Tough to make complete sense of that, Plymouth. The length is not important as we are generally discussing a typical home music system installation where front speakers are placed to maintain the shortest posible cable length.

As a rule we also tend to dismiss those cables with impedance values (or other oddities) which would render them out of the ordinary and which would therefore obviously affect the system performance. Cables as tone controls or cables which send an amplifier into oscillation are not the issue here though a few people still believe this is the major benefit of biwiring. This is similar to your experiment with a tube amp on top and a solid state amp beneath. Such systems are being tailored to a specific tonal balance and are therefore outside of the stated goals for most high end systems. I'm not disparaging such choices, just saying they are not a clear representation of biwirings benefits.



" ... a absolute zero ohms can't doing any difference ... "


I'm going to guess you are referring to the ground plane of the crossovers as there can be no "absolute zero" impedance when measuring a cable. See my above comments to GW regarding ground planes.



"the thing is that a wire is not a supra conductor but pure copper without oxygen give a much more result especially if it contain many conductor individually
shielded."



As noted, we are not discussing the out of the ordinary contruction of a particular cable. In any event, oxygen free conductors and the number or gauge of conductors have no distinct effect on whether biwiring is effective or not. As with GW, I believe you are looking too narrowly at only one component within the entire circuit.



"I saw cheap Chinese cable doing much better than Monster cable to 40 times the cost."


Why does everyone beat up on Monster Cable?

Plymouth, cost is not an issue in the discussion of biwiring. Either biwiring is effective or it is not. We all know high end audio is a trickle down game. If biwiring works at all, then it is an effective way to improve performance. If that has been proven, then we need only wait for the enterprising designer who can bring those benefits down to a price range acceptable to the majority of buyers.


As to your test equipment, once again, refer to my post to GW. It is quite possible you are not looking in the right place or at the complete picture.


.
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15295
Registered: May-04
.

Just to let everyone know the facts on my end of this, I do not now own nor have I ever owned a pair of speakers which offered biwiring capacity. It would, therefore, be impossible for me to reach any conclusion " ... based on your desire to hear a difference to justify the money spent ... ". I have not spent money for speakers or cables which have to do with biwiring, therefore I have nothing to justify to you or to myself pertaining to my actions or beliefs. The conclusions I have reached are based upon my belief that many listeners have accurately perceived improvements when converting to a biwire configuration. I have also taken into account the technical information I have already possessed and that which I have found while doing research into the hows and whys of the debate.

If someone feels this disqualifies me from the discussion, then you are perfectly welcome to immediately end your part of this conversation.


.
 

Platinum Member
Username: Plymouth

Canada

Post Number: 14981
Registered: Jan-08
"the thing is that a wire is not a supra conductor but pure copper without oxygen give a much more result especially if it contain many conductor individually
shielded."


As noted, we are not discussing the out of the ordinary contruction of a particular cable. In any event, oxygen free conductors and the number or gauge of conductors have no distinct effect on whether biwiring is effective or not. As with GW, I believe you are looking too narrowly at only one component within the entire circuit.

I do not approve your answer because the accuracy of the sound passes by there, I know that cable play with the frequencies especially that the conception of cable modifies the frequencies and helps to correct certain defect of the system in acting like a capacitor, al cables does not sound identical,

What arrives if the amplifier is directly hooked with a bi-wirings speaker?
The answer is none difference!!!!!

My first reply was under this but we all know that no cable is perfect then we will see a difference in sound.

On this your pretending of using bi-wirings is totally right then I agree with you on this.

My search of purity was under my controversial answer but in practice you are totally right!

Best regard!
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15296
Registered: May-04
.

Not sure what to make of that post, Plymouth.
 

Platinum Member
Username: Plymouth

Canada

Post Number: 14983
Registered: Jan-08
For those who do not know why there is a difference with the bi-wiring, here is my answer which is not a C / P purpose my understanding of the phenomenon!

Imagine a low frequency which drop the gain at the end of speaker but can't affect the amplifier because of impedance of the wire, the mid and high frequency will drop for the same amount on the tweeter causing a distorsion of the initial signal that the amplifier can't correct because this signal is not return to this one, now let us use bi-wirings, the mid and high frequencies will not be affected by the great power asked by the woofer and this signal is going to be returned without decrease of the signal making purer and more just mid and high frequencies.

That's why the impedance has an impact on the tone.
 

Platinum Member
Username: Plymouth

Canada

Post Number: 14984
Registered: Jan-08
>Not sure what to make of that post, Plymouth.<

Why Jan?
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15297
Registered: May-04
.

Well, for starters, I wasn't looking for your "approval" or disapproval.

If I understand your post correctly, what you are describing is something so far fetched in terms of the impedance of a cable which so drasticaly affects the overall gain of the signal as to be out of the ordinary in virtually every respect. Tell me what sort of measurements you would expect to find in a cable with this sort of performance. How does this cable not affect the amplifier but just certain frequencies?



As I said, Plymouth, we have to maintain some sense of normalcy for this to be relevant. We can't pull "what ifs" off the shelf to make an explanation work in a minimal number of all together unusual circumstances. The benefits of biwiring have been reported in a wide range of systems, not just those with cables which seriously compromise the signal quality.



.
 

Platinum Member
Username: Plymouth

Canada

Post Number: 14985
Registered: Jan-08
Jan

Again I agree with you and explain why this happen, I tested a 0 gauge copper wire used for electric installation to see what can be the difference in tone, result the high frequencies was in back in comparaison with low frequencies!

Why?

Only because the low frequencies was done without any loss!

The result with the high frequency was a purer and detailed sound!

If you are able to read the diagram of an amplifier, you will see that they usualy use a correction in the damping loop which playing with the final result. Without this filter the sound is more detailed and the depht of the room is greater.

What is the principal use of damping?

To give a lower distorsion to provide better spec which correct defaults of bad amplifier! It work like this: take the output to compared with the imput to make the correcrion to the output but this kind of test is made on a resitive charge and not on a speaker that's why usualy a high cost amplifier does not give the best distortion on the market.
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15299
Registered: May-04
.

Plymouth, did you say you too are an engineer? I know of nothing termed the "damping loop". I believe you are confusing this with the "negative feedback loop".
 

Platinum Member
Username: Plymouth

Canada

Post Number: 14986
Registered: Jan-08
Jan

Sorry you know that I'm a French Canadian!

Yes I talk about ''negative feedback loop''!

When you read the damping factor, it tell you the amount of this negative feedback act on the output.

No I'm not ingineer but I play in elctronic since I had 8 years started with tube, I have 48 years today, I worked with Bose ingeneer under using with the Bose 901 at their beginning like student, I had a electronic repair shop with the beginning of the VCR, worked like recordman in studio, I'm a electrothechnician specialized in motor drive, recently partialy worked for GroupeSPL like audio technician, lighting tech and electrician etc....
 

Gold Member
Username: Magfan

USA

Post Number: 1648
Registered: Oct-07
Jan, would my panels be considered candidates for biwiring?
I'd love to remove the jumpers. Each 'side' of the speaker would have it's own ground path.

Plymouth, amps, at least a/b amps are no more than about 55% efficient....from plug to speaker. You must, at some time, charge the capacitors. The average power used by the amp should always be higher than the average output power of the same amp. No?
75amps is a lot of current. I'm sure this current is delivered at only a few volts, and than not for very long.

My panels, which are considered to need more power....than some more, have only a 4 amp fuse on the mid/tweeter. If the speaker can take say.... 10 amps continuous I'd guess that 40 or 45 volts would be about it... certainly no higher than 50 volts.
Where do you get the value of 75amps? How much current does your amp draw when you turn it on? Have you measured power line sag? I would suggest that with all the reactance of your power supply, the power factor is very low. Try a Kill-a-Watt meter. They are very inexpensive.
 

Platinum Member
Username: Plymouth

Canada

Post Number: 14990
Registered: Jan-08
Hi Leo!

Sony sold a amplifier with 2x 250 watts RMS with a transformer of 300 for both channels, their reference! LOL!

My modified Adcom is originaly listed for a consumption of 300 watts for 2 x 60 watts uner 8 ohms but with 2 transformers of 500 watts each.

75 amps is the total of darlinton transistors(3 x 25 amps each, 6 total for each channels in push/pull), the output voltage from the power supply is 45+ then 45 - for a total of 90 volts, the two original transfo furnish about 6 amps under 90 volts each which go true a 50 amps bridge for each channels to the both pack of capacitors for each channels.
On the cliping low wave the power supply drop under 78 volts DC, the original output fuses was 5 amps but I use now 8 amps
soldered due to the contact oxydation.If I only short the speaker lead at low volume the fuses blow immediately.

I runned this ampli with 2 pairs of 6 ohms and a pair of 8 ohms speaker in my old house, now with the home theater only the IMF Reference Professional Mark IV are hooked, certainly the voltage will be higher because my reading was made with 6 speakers.

Evaluate the power factor is realy hard because this amp can drive as low that 1 ohms, I let you calculate how much watts RMS this ampli can provide, I estmated to about 80 watts per channel under 8 ohms then due to the very strong power supply 320 watts under 2 ohms.

>How much current does your amp draw when you turn it on?<

I can check the peak for you but I can tell that the light inside the house drop more than my industrial compressor of 5 HP which drain over 120 amps on the start.
I don't need a Kill a watts meter to check the consumption, I can simply use a good AC ampere clamp which I multiplie by the voltage to have the wattage> I x V=Watts.

>I would suggest that with all the reactance of your power supply, the power factor is very low.<

If you reffering with the car capacitors like a 25 farads, no! my capacitors are made by the reputy company Mallory and does not drain the power like a car Capacitor!

I can't talk about your panel which I presume are electrostatic?

If yes, those electrostatics need more amperage for one reason, the surge of static drain a high voltage which cause lightening in the amplifier and destroy the transistors.

Yes you can use bi-wiring for your panel!

Best regard!
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15300
Registered: May-04
.

Plymouth, in the grand scheme I think you have the overall idea of biwiring more or less figured out. However, you have many of the facts regarding negative feedback backwards or incorrect.



"I tested a 0 gauge copper wire used for electric installation to see what can be the difference in tone, result the high frequencies was in back in comparaison with low frequencies!"


I know of no consumer audio connectors which can accept a 0 AWG cable. So, I assume you had intermediary connectors. 0 AWG cable used for electrical installations is not of the same construction as any sort of acceptable audio grade speaker cable. You are changing too many factors to make this a valid comparison. I too would expect a diminished high frequency content (among other subjective changes) with inferior grade cabling.


"Only because the low frequencies was done without any loss!

The result with the high frequency was a purer and detailed sound!"



The cable has no ability to determine its frequency response. Even a solid core 0 AWG cable 10' in length should indicate a flat frequency response from 20-20kHz. The total impedance of a 0 AWG cable should be so low as to not be of consequence to the amplifier/speaker circuit, there should be no additional interaction between amplifier and speakers due strictly to the insertion of such a cable. Your subjective impression of "purer" high frequency content is attributable to some other factor beyond altering the gauge of the cable.


"If you are able to read the diagram of an amplifier, you will see that they usualy use a correction in the damping loop which playing with the final result. Without this filter the sound is more detailed and the depht of the room is greater."


Here I don't know what you are referring to. It was at one time common for consumer amplifiers to include a Zobel network (http://search.yahoo.com/search?ei=utf-8&fr=slv8-hptb5&p=zobel%20network&type=. The inclusion of this circuit was meant to flatten the overall impedance of the load which would make the reactance of the typical speaker far less of an issue with most amplifiers. The network also cost the amplifier usable power in the real world. Most high quality amplifiers have long ago dropped the Zobel in favor of a more direct coupling to the speaker load which has its advantages and disadvantages. While it is relatively simple to eliminate a Zobel network from the signal path, it is not so easy to do away with the negative feedback loop.

If you are suggesting removing the NFB, this would require a total overhaul of the amplifier circuit as NFB affects several critical factors in an amplifier's operation. The NFB circuit will lower output impedance for the circuit to which it is applied, it will adjust gain within the circuit and it will lower total harmonic disortion at the output of the circuit. (It will also tend to make an amplifier more stable into a reactive load when used in moderation but will push an amplifier over the edge into instability and the incapacity to deal with highly reactive loads when its use is applied as a patch to a poorly designed and poorly implemented amplifier.) Therefore, removing a NFB loop is impossible to do and still call the end result a similar amplifier to the one you started with.


"What is the principal use of damping?

To give a lower distorsion to provide better spec which correct defaults of bad amplifier! It work like this: take the output to compared with the imput to make the correction to the output but this kind of test is made on a resitive charge and not on a speaker that's why usualy a high cost amplifier does not give the best distortion on the market."



I can't find much to agree with in that statement, Plymouth. Yes, as I stated above the application of NFB (not damping) is intended to lower THD. NFB became a BandAid in the 1970's when the emerging Japanese receiver market applied excessive NFB in order to put on paper specs which uninformed consumers often used as a comparison value. This, unfortunately, gave rise to zero NFB amplifiers in the high end market which could not deal with the real world loads presented by the speakers of the day.

The end result tended toward high end amplifiers which did not rely on global feedback circuits - those which ran from the "-" terminal of the speaker connector back to the front end input of the amplifier. Higher quality amplifier designers still needed the NFB loop to stabilize the amplifier when it was working into a reactive load such as a (most)real world loudspeakers, so NFB slowly has come back into the discussion of quality amplifier design. This "need for NFB" is espcially true with solid state designs which would (and did) literally implode when the NFB loop was completely removed. Tube based power amplifiers, however, can and have run with only localized feedback loops for decades. This is often cited as one of the many advantages of vintage tube gear, many of the higher quality tube amps from the 1950-60's ran with only a few dB of feedback localized around specific circuits. (For example, the triode tubes used as pre amp, input or driver tubes in most tubed amplifiers have an inherent cancelling of odd order distortion components which acts very much like the NFB circuit in a transistor amp. Therefore, by using the triodes, the amplifier designer has no real need for global feedback other than lowering the overall cost of the amplifier.)

High quality amplifiers tend to measure well. If they are outdone on paper by low cost receivers, it is more due to the fact the numbers presented by the high end manufacturers are likely to represent the worst case, real world conditions for the high end amplifier vs the idealized spec's stated as the design goal for many cheap receivers. Testing facilties such as Stereophile employ "simulated speaker loads" when testing for amplifier performance. Less strict testing can be performed on receivers with a simple non-reactive load resistor.


"That's why the impedance has an impact on the tone."

Impedance matters due to Ohm's Law. With a relatively high output impedance the amplifier will respond to the reactance of the load as predicted by Ohm's Law. As the speaker's impedance dips and rises the amplifier will produce more or less "power" into that impedance load. Amplifier's with high output impedance coupled to a highly reactive speaker load will tend to sound bassy or thin, bright or rolled off as the amplifier/speaker circuit does what Ohm's Law predicts. Amplifiers with extremely low output impedance will tend to offer flatter response overall no matter the reactance of the load. That is a vastly simplified ideal which is seldom met in reality as achieving that low output impedance can have serious consequences in other areas of the amplifier's operation.



.
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15301
Registered: May-04
.

"When you read the damping factor, it tell you the amount of this negative feedback act on the output."


Well, no, reading the damping factor cannot tell you anything about the amount of feedback applied within the amplifier. Damping factor is nothing more than a marketing number in most people's mind. It was created during the 1940-50's to market higher quality pentode based, push pull amplifiers - most particularly those which followed the (then) newly introduced Williamson circuit - and to distinguish them from the "old fashioned" triode and single ended amplifiers which had preceded them in the years prior to the War. Since its introduction, damping factor has been a somewhat controversial specification. Bob Carver made it more important (than it needs to be) when marketing his Phase Linear line of products. Suddenly Phase Linear amplifiers were touting a 1000:1 damping factor against the competition of the day who were stating a modest 50:1 or possibly with a direct coupled transistor amplifier a 100:1 spec.

Damping factor is a completely on paper spec. It varies with frequency and the reactance of the load and, therefore, has little value in the real world. It is determined by taking the "nominal" impedance of a non-reactive, assumed 8 Ohm speaker load and dividing it by the "nominal" output impedance of the amplifier. If you understand the operation of an amplifier, you can see how this number is for all intents a truly pie in the sky spec.

Since there are numerous other facotrs which determine the same values affected by NFB, there is no simple one to one relationship between the stated damping factor of an amplifier - and the difference between global and localized feedback circuits - there is no direct one to one relationship between damping factor and the amount of NFB employed in the amp's design.


.
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15302
Registered: May-04
.

"Jan, would my panels be considered candidates for biwiring?
I'd love to remove the jumpers. Each 'side' of the speaker would have it's own ground path."



I have no idea, Leo. Biwiring is a suck-it-and-see-what-comes-out sort of affair. Most dealers have biwire cables they will loan out for a weekend's experimentation and that's the best way to find out for yourself in your specific system whether biwiring will be of any significance. If you've followed what I have described above, you should understand that biwiring is a case by case issue. The design of the speaker and its crossover design and layout most especially are of prime importance. But equally so is the amplifier. If your amp has little to no global NFB, then your system is far less likely to respond to biwiring. Speakers which tend towards a more reactive load or which exhibit higher levels of back EMF than your panels are also found on average to be "better" candidates for biwiring. On the other hand, those flattened speaker diaphragms of the panels are known to be unkind to many amplifiers, back EMF is not unheard of in Magnepans.

However, in the end, it is the entire circuit from amplifier outputs through the complete speaker system and back to the amplifier's "-" return leg which matters. The "-" speaker terminal at the amp is typically where a NFB circuit will take its input and therefore have its most dramatic affect when changes are made at that point.

Alternatively, biwiring can, if you so desire, be used as Plymouth explained, to tailor a system's performance by using cables as tone controls. Rather than having one cable which imparts its "sound" on the entire system, you can add a "bright" cable for the high end and a "fast" cable for the bottom. IMO this gets a bit tricker than finding cables which are more neutral throughout the frequency range but this is one option available when you biwire. Certainly, as everyone has agreed, bi-amping is the far more effective way to deal with the problems biwiring only hints at.


.


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Platinum Member
Username: Plymouth

Canada

Post Number: 14994
Registered: Jan-08
As you seem not understand what I said, read it to understand that the Negative feedback is the Damping factor.


C/P from Wiki

Damping factor
From Wikipedia, the free encyclopedia
Jump to: navigation, search

The term damping factor can also refer to the amount of damping in any oscillatory system or in numerical algorithms.

In audio system terminology, the damping factor gives the ratio of the rated impedance of the loudspeaker to the source impedance. Only the resistive part of the loudspeaker impedance is used. The amplifier output impedance is also assumed to be totally resistive. The source impedance (that seen by the loudspeaker) includes the connecting cable impedance. The load impedance Zload (input impedance) and the source impedance Zsource (output impedance) are shown in the diagram.

Source and load circuit Z.png

The damping factor DF is:



[edit] Explanation

In loudspeaker systems, the value of the damping factor between a particular loudspeaker and a particular amplifier describes the ability of the amplifier to control undesirable movement of the speaker cone near the resonant frequency of the speaker system. It is usually used in the context of low-frequency driver behavior, and especially so in the case of electrodynamic drivers, which use a magnetic motor to generate the forces which move the diaphragm.

Speaker diaphragms have mass, and their surrounds have stiffness. Together, these form a resonant system, and the mechanical cone resonance may be excited by electrical signals (e.g., pulses) at audio frequencies. But a driver with a voice coil is also a current generator, since it has a coil attached to the cone and suspension, and that coil is immersed in a magnetic field. For every motion the coil makes, it will generate a current that will be seen by any electrically attached equipment, such as an amplifier. In fact, the amp's output circuitry will be the main electrical load on the "voice coil current generator". If that load has low resistance, the current will be larger and the voice coil will be more strongly forced to decelerate. A high damping factor (which requires low output impedance at the amplifier output) very rapidly damps unwanted cone movements induced by the mechanical resonance of the speaker, acting as the equivalent of a "brake" on the voice coil motion (just as a short circuit across the terminals of a rotary electrical generator will make it very hard to turn). It is generally (though not universally) thought that tighter control of voice coil motion is desirable, as it is believed to contribute to better-quality sound.

A high damping factor indicates that an amplifier will have greater control over the movement of the speaker cone, particularly in the bass region near the resonant frequency of the driver's mechanical resonance. However, the damping factor at any particular frequency will vary, since driver voice coils are complex impedances whose values vary with frequency. In addition, the electrical characteristics of every voice coil will change with temperature; high power levels will increase coil temperature, and thus resistance. And finally, passive crossovers (made of relatively large inductors, capacitors, and resistors) are between the amplifier and speaker drivers and also affect the damping factor, again in a way that varies with frequency.

For audio power amplifiers, this source impedance Zsource (also: output impedance) is generally smaller than 0.1 ohm (&#937;), and from the point of view of the driver voice coil, is a near short-circuit.

The loudspeaker's load impedance (input impedance) of Zload is usually around 4 to 8&#937;, although other impedance speakers are available, sometimes as low as 1&#937;.
[edit] The damping circuit

The voltage generated by the moving voice coil forces current through three resistances:

* the resistance of the voice coil itself;
* the resistance of the interconnecting cable; and
* the output resistance of the amplifier.

[edit] Effect of voice coil resistance

This is the major factor in limiting the amount of damping that can be achieved electrically, because its value is larger (say between 4 and 8&#937;, typically) than any other resistance in the output circuitry of an Output TransformerLess amplifier.
[edit] Effect of cable resistance

The damping factor is affected to some extent by the resistance of the speaker cables. The higher the resistance of the speaker cables, the lower the damping factor. When the effect is small, it is called voltage bridging. Zload >> Zsource.
[edit] Amplifier output impedance

Modern solid state amplifiers, which use relatively high levels of negative feedback to control distortion, have extremely low output impedances--one of the many consequences of using feedback--and small changes in an already low value change overall damping factor by only a small, and therefore negligible, amount.

Thus, high damping factor values do not, by themselves, say very much about the quality of a system; most modern amplifiers have them, but vary in quality nonetheless. Given the controversy that has long surrounded the use of feedback, some extend their distaste for negative feedback amplifier designs (and so a high damping factor) as a mark of poor quality. For them, such high values imply a high level of NFB in the amplifier.

Tube amplifiers typically have much lower feedback ratios, and in any case almost always have output transformers that limit how low the output impedance can be. Their lower damping factors are one of the reasons many audiophiles prefer tube amplifiers. Taken even further, some tube amplifiers are designed to have no negative feedback at all.
[edit] In practice

Transient oscillations in electric circuits are normally reduced (damped) by inserting resistance into the circuit, or reactance (which increases resistance in the frequency region requiring damping).

This technique cannot be used with loudspeakers, because increasing the mechanical resistance to cone movement would make the speaker less efficient, requiring larger amplifiers. For high fidelity use, such speakers would be less capable of responding properly to musical or speech transients. Instead, the generator effect in voice coil drivers is used to damp oscillations electrically.

Damping factor describes the ability of the amplifier to control unintended movement of the speaker cone near the resonant frequency of the driver. Other things being equal, a high damping factor indicates that an amplifier will have greater control over the movement of the driver cone, particularly in the bass region near the resonant frequency of the driver.

The higher the resistance of the speaker cables or the output impedance of the amplifier, the lower the damping factor, since the resistance seen by the voice coil will increase. The damping factor is affected to a small extent by the resistance of the speaker cables, and for most amplifiers, to small changes in the output impedance of the amplifier.

http://en.wikipedia.org/wiki/Damping_factor
 

Platinum Member
Username: Plymouth

Canada

Post Number: 14995
Registered: Jan-08
Again the impedance of the wire play on the control of the speaker.

The high amperage of amp section then a strong power supply help to control the speaker, I talk of it because I tested it after I see it in a reputy revue 20 years ago.
My amp and my speaker can accept #0 wire with a copper terminal for battery of car!
 

Gold Member
Username: Magfan

USA

Post Number: 1650
Registered: Oct-07
I don't know how much NFB my 'd' amps use.....either input to output....'global' or at any given gain stage.
Panels are generally a low reactive load and don't store much energy.
I think my best best would be a 2-step, careful program.
1. Get rid of the fuse. A quick solder job, moving a wire from one side of the fuseholder to the other.

2. Better jumpers between hf/lf crossover sections.

Maybe part 3 would be to get away from the Banana plugs and go to a better, 'real' termination.

Plymouth:: You'd have to be using some wacky stuff to need 0 gauge wire. I read the DF section very differently. The amp with low resistance to back EMF actually allows the speaker to damp itself. Debate rages about how much DF is needed. Tube guys with low reactive, single driver speakers would say a low value is fine, while the SS guys can sometimes brag about DF in the 5 digit range. And they sometimes have the speakers to prove it!
 

Platinum Member
Username: Plymouth

Canada

Post Number: 14998
Registered: Jan-08
Leo

LOL! No it was purely to analize the difference between very big wire then usualy used wire.

Here is what I use:
Upload
Sorry for the dust!

This is not a new debate, this debate was started since it was introduce.

I'm surprise to see that it was not discussed here!

Is there one hardware which produce worst distorsion that a speaker, introduced the NFB was only to reduce the distorsion, nothing more, the higher cost tube amplifier do not use this kind of negative feedback but sound purer. The NFB introduce a resonant high frequency where you lose the clarity.

Like as mentionned on wiki, it work well on low frequency but less on mid/high freq, some manufacturer diverted this problem in using the NFB only on low frequency but the result is a lack of detail in some frequencies.

What brand and model of panel speaker you have?
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15303
Registered: May-04
.

"As you seem not understand what I said, read it to understand that the Negative feedback is the Damping factor."


No, it is not. The two are not strictly related. The amount of NFB is constant across all frequencies and with no relation to the load impedance. It is the same no matter whether the amplifier is driving an electrostatic panel or a simple load resistor. No matter the load impedance or characteristics of the speaker, the amplifier's output impedance remains constant at any one frequency and only varies as frequency rises and falls. At best, output impedance has no direct correlation to NFB.

Damping factor is a completely made up number as your Wiki link suggests. You cannot look at the damping factor specification and come up with a realistic guess at how much NFB is in use.



"Again the impedance of the wire play on the control of the speaker."


Again, speaker cables with sufficiently high impedance values are out of the norm. That doesn't mean they do not exist but such cables are not useful when discussing biwiring. Obviously, the amp/cable/speaker/cable/amp circuit must contain the value of the cables. However, unless you are intentionally try to deviate away from neutral performance, such cables are not going to provide consistent and repeatable results.


"The high amperage of amp section then a strong power supply help to control the speaker."

Uh, not exactly. There are numerous ways to control the loudspeaker.



Plymouth, I hope you won't make me argue with someone who has exposed filter/storage capacitors hanging out of the open back panel of his amplifier.





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Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15304
Registered: May-04
.

http://www.bcae1.com/dampfact.htm

http://www.lautsprechershop.de/tools/index_en.htm?/tools/t_kabel_en.htm


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Platinum Member
Username: Plymouth

Canada

Post Number: 14999
Registered: Jan-08
Jan
In your first link, we can see how seriously they make the test:

Damping Factor Tests

Standards:
If you are going to test more than one amplifier, you should adopt some standards. You should pick a single frequency or a defined set of frequencies. You should also pick a load with a commonly used impedance (such as 2 or 4 ohms). For this example let's say that the test frequency is 50 hertz and the test load's impedance is 4 ohms.

Testing:
For this test, you want to drive the amplifier to a sufficiently high level to produce large numbers. Since your test equipment has a limited number of decimal places, the larger numbers will help increase the accuracy of the tests. You will drive the amplifier to a level which will be below clipping when loaded with the test load. You must be absolutely sure that the level of the input signal is not changed throughout the test procedure. Measure and make note of the output voltage of the amplifier with no load. Connect the 4 ohm load to the amplifier's output terminals and measure the output voltage again. Make note of it. Please note that the voltage measurements should be taken as close to the amplifier as possible. OK, enough of that.


How many time I mentionned that the difference is in high frequencies then they try it with 50 hertz!

My amp does not drop even I put 2 more pairs of speakers only on clipping!

Also this site come from Car audio which is not a reference!


The second lind look like amateur with those cheap speaker!

Jan

You argue with nothing to proove that those debatable link! I can't believe you refer it to debate your point!

I will repeat again>>> a very strong power supply, high power transistors then the lower impedence between the amp and the speaker does not need or only few damping according with the quality of amplifier.

Best regard!
 

Platinum Member
Username: Plymouth

Canada

Post Number: 15000
Registered: Jan-08
Damping Factor

Having established that resistance within reason is not an issue as regards power loss, there is damping factor to be considered. Quite apart from the fact that "damping factor" is a rather ill-conceived term, we need to look at the reality of what the amplifier is capable of controlling within the speaker cabinet.

According to some, damping factor should ideally be infinity +/- 3dB so the amplifier is in total control of the speaker. What utter rubbish. The loudspeaker is an electro-mechanical device, and its sensitivity to external impedance is easily tested. Indeed, if the amp were in total control, with the amplifier connected (and turned on), you would not be able to move the cone at all by pressing it. Motional feedback can be used, but that's a completely different approach and will not be covered here.

Try this experiment. Disconnect the speaker leads from the speaker, and tap the cone lightly with your fingers - listen very carefully to the character of the "thump" of the speaker. Now, connect a short piece of stout wire directly between the speaker terminals - this will have a resistance so low as to be considered 0 Ohms.

Tap the cone again, the same way as before. Can you hear a difference? I would expect that you can, because if not the speakers are either so well damped internally that the amplifier's contribution is irrelevant, or there is so much internal resistance that no amplifier can save them.

Now, remove the short, stout wire, and replace it with a 4 metre length of bell wire or telephone cable. Tap the speaker cone again, and listen carefully to see if there is any difference between the sound with the "dead short" versus the piece of rubbish you just connected, which might typically have a resistance of 0.5 Ohm (maybe more).

Could you hear any difference? If you have access to an AC millivoltmeter, you should try to measure a voltage as you tap the speaker cone. You will typically find that very little change will be evident in the character of the sound between the dead short and the bell wire, and only a small voltage (a few millivolts) will be indicated.

This is a rather extreme test, and it is quite possible that a very slight difference in "tonality" will be observed. It is equally possible that you will not be able to hear any difference whatsoever, despite the fact that damping factor has been reduced to a small fraction of its former value with the dead short circuit created by the short wire. I suspect that most people assume that the back EMF from a driver is much higher than it really is. As an experiment, I attached two drivers together - face-to-face. Since both have a rubber roll surround and this made contact, the coupling between the cones was very good indeed.

The driven speaker was a Vifa P13WG, 8 ohm - the driving speaker was the same size, but an unknown brand. The driving speaker was then driven with 2.6V RMS at 175Hz, and considerable cone movement was visible for both drivers. The open-circuit voicecoil voltage was measured at 670mV, and short-circuit current measured at 76mA. The Vifa voicecoil was able to generate a voltage of 341mV into an 8 ohm load (43mA). So with a nominal 845mW driving power, even direct coupled cones could manage only 51mW output. Back EMF (and the resultant current) from drivers in a properly damped enclosure will be normally be a lot smaller than expected.

Even the best amplifier in the world will have some impedance, as will the most expensive cable. These can actually be "removed" completely by building an amplifier with a negative output impedance, but having tried this approach, I can assure the reader that a horn compression driver is the only speaker I have ever tested which sounded better with negative impedance. All other speakers, whether horn loaded, sealed or vented box sound universally dreadful with negative impedance.

Negative impedance is exactly what it sounds like - the amplifier is modified so that the voltage output rises with increasing load. This is surprisingly simple to implement, but speakers seem to hate it - most seem to prefer a small but measurable amount of positive impedance. This is the equivalent of using a cheap speaker lead, but has other implications - there is no loss of power due to the resistance of the lead, and high frequencies are far better since there is none of the capacitive loss incurred by the really cheap speaker lead.

Have you ever wondered what it is about valve (vacuum tube) amps that has many audio enthusiasts drooling over the latest - usually extremely expensive - offering from this manufacturer or the other?

They will wax lyrical about the extended bass, and the sweetness of the highs etc. etc. One of the things about valve amps is their relatively high output impedance - this may be up to about 6 Ohms for an amp without any feedback, and will rarely be less than about an Ohm (8 Ohm output selection is assumed). The damping factor is obviously grossly inferior to that of a transistor amp (although some of the premium amps of the late 60s and early 70s came very close indeed), but the sound quality is generally considered more musical, or "sweeter" by a great many enthusiasts.

There are many other factors involved than simply the output impedance, but if this were so important (or as important as some would have you believe) then valve amplifiers would be universally condemned for their poor low frequency performance - phrases such as "woolly", "muddy" and "over-emphasised" spring readily to mind. Instead, we can read reports where reviewers have praised the low frequency performance, claiming an extra 1/2 octave or so of bass extension. This is in spite of the fact that very few valve amplifiers can actually make it down to 20Hz without rolloff and output transformer saturation distortion starting to be readily observable.

Well before transformer saturation distortion and other undesirable effects make themselves known, the output impedance rises. This is at the very frequencies where damping factor is supposedly most important. Yet these amplifiers continue to receive rave reviews from listeners - we must conclude that the damping factor cannot be as important as is so often claimed. Could it be that all owners of valve amplifiers have tin ears, and couldn't tell the difference between a symphony orchestra and a bag of cat litter? This is possible, I suppose, but I do believe that it is somewhat unlikely !

I shall not go so far as to say that the myth is disposed of, but I believe that an extremely low amplifier output impedance is not as important as many people think it is, and that in some cases a small (preferably controlled) amount of deliberately introduced impedance is useful for correcting the characteristics of a loudspeaker driver whose Q is lower than desirable for the enclosure design used. Indeed, I have made such modifications to equipment - raising the output impedance of the amp so that a studio monitor driver could be matched more exactly to the enclosure, and this was at the request of the speaker designer.

http://sound.westhost.com/impedanc.htm

This link explain well also the damping:
http://www.amplifier.cd/Tutorial/Innenwiderstand/output_resistance.htm
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15305
Registered: May-04
.

Plymouth, why are we discussing damping factor in the first place? It has nothing to do with biwiring.


None the less; "How many time I mentionned that the difference is in high frequencies then they try it with 50 hertz!"


The test was performed at 50 Hz because it is the low frequency driver(s) which exerts sufficient back EMF to cause the amplifier problems. Equally, due to its mass/diameter and the distance the driver travels from stop to start it The low frequency driver) is the driver with the most obvious inertia, distortion and resonance issues. A conventional, dynamic type midrange or high frequency driver has none of these issues in sufficient amounts to constitute a problem for any competent amplifier.

Damping factor on paper is frequency independent as it does not concern itself with frequency variance which would occur under real world music material conditions. A point you should be able to deduce from the two calculation sites I linked to.

Maybe the tester didn't get your message about high frequencies. Or, maybe, since high frequencies are not an issue in calculating the damping factor spec, the tester didn't care what you had said. Look, Plymouth, damping factor is calculated by taking the (resitive component only from the) output impedance of the amplifier (including cable resistance) and dividing it into the resistive component of the (assumed) nominal speaker load. Actually, the "impedance" component of the load isn't of any concern to calculating damping factor, only the resistive value.

Nothing about frequency is in the calculation for damping factor.

You cannot directly measure damping factor, you can only calculate the equation by referring to other extraneous measurements. Any calculation you would make would only be of value for the specific frequency at which all those values would concur. In other words, the damping factor at 50Hz is not the same as the damping factor at 15kHz.

Nothing regarding NFB is in the calculation for damping factor.

Damping factor has nothing to do with biwiring.




That's why I introduced those two links, the calculation doesn't change from car stereo to consumer to pro audio. So, please, get off your high horse about my links. You can go anywhere and find the same method for calculating damping factor. You introduced Wiki links and then give me grief for a car stereo link?!!! PLEASE!!!




"My amp does not drop even I put 2 more pairs of speakers only on clipping!"


None of this has anything to do with damping factor, NFB or biwiring. What your amplifier does or does not do is not relevant to this thread.


"The second lind look like amateur with those cheap speaker!"


That is a subjective opinion. However, no matter what you think of the site, I could understand what was being said which is more than I can usually manage with your posts, Plymouth. You're really reaching for something - anything - when you disparage the look of a speaker on a website about math. C'mon, Plymouth. You don't talk about the speaker's appearance and I won't talk about the Litz type cabling you're running for speaker cables from automobile battery connectors grafted onto the back of your open chassis amplifier. OK?


"I will repeat again>>> a very strong power supply, high power transistors then the lower impedence between the amp and the speaker does not need or only few damping according with the quality of amplifier."


You're welcome to believe that - but you're wrong. And none of that has anything to do with NFB, damping factor or biwiring.


Nothing in your links mentions NFB as being calculated from damping factor specs. NFB and damping factor are linked due to the NFB reducing the output impedance of the amplifier. But there is no one ot one realtionship between DF and the amount of NFB employed. To the best of my knowledge, that is how we started this BS. You stated, "When you read the damping factor, it tell you the amount of this negative feedback act on the output."



That is incorrect.






Consider this, Plymouth, NFB is fixed within the amplifier as to amount in dB's. It does not vary widely dependent upon the load. However, if you calculate DF, you would find the DF spec changes when the load changes. DF is higher for a 16 Ohm load and lower for a 4 Ohm load. Meanwhile, NFB remains constant within the amplifier loop, certainly this is the case for localized feedback circuits as found in high quality amplifiers. This general description may not be the reality of how the NFB circuit operates in the real world in all amplifiers but it is close enough for this discussion.

From your second link, "A regulation is based on the principle of the negative feedback and a much higher open loop gain than a closed loop gain. Also a Hifi amplifier has an output resistance. Since a closed loop is present, I speak now of a dynamic output resistance. Dynamically therefore, the amplifier tries to regulate the output voltage, since it accomplishes continuously an actual value with desired value comparison. In other words, an amplifier is a DC source voltage with a very fast adjustable internal resistance. Since a constant continuous (following the signal) dynamic adjustment of internal resistance happens here, I call this internal resistance: dynamic internal resistance in the respective operating point. The measurement of dynamic internal resistance effected as in fig. 4 described, as signal source is set an alternating voltage on the amplifier. Dynamic internal resistance has validity for this operating point only.








At this point, Plymouth, I realy do not understand what it is you're trying to prove. The thread was about biwiring. None of this has anything to do with biwiring. NFB has to do with biwiring but neither biwiring nor NFB have any relationship to damping factor.






And I don't care how dangerous you've made your amplifier.






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Platinum Member
Username: Plymouth

Canada

Post Number: 15003
Registered: Jan-08
If you don't care with you tell it!

I started this thread to debate on this subject since that you seem not like debated it here!

https://www.ecoustics.com/electronics/forum/home-audio/656282.html
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15306
Registered: May-04
.

Plymouth, I have no idea what either of those two sentences are supposed to mean.

You're welcome to start all the threads you want but my answer isn't going to change. The DF spec does not inform you of the amount of NFB employed in an amplifier - most high quality amplifiers employ localized NFB which in many/most cases is not affected by the back EMF of the speaker system. DF is a made up spec - it means nothing.

You stated, "When you read the damping factor, it tell you the amount of this negative feedback act on the output." That is incorrect. And then you launched into this ... whatever? on damping factor.

You are becoming quite confrontational on this as best I can make out from the broken English you use. I don't understand why. Nor do I understand why you feel you must be confrontational over damping factor which has nothing to do with biwiring.


.
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15307
Registered: May-04
.

You didn't like a link to a car stereo mathmetician and you didn't think the second link was useful because you didn't care for the look of the speakers represented in a math article. How about one from Crown Amplifiers?

http://crownaudio.com/pdf/amps/damping_factor.pdf


No reference to NFB and the graph indicates a DF which varies with frequency.


.
 

Gold Member
Username: Magfan

USA

Post Number: 1653
Registered: Oct-07
Plym:
I've been a Magnepan owner for decades. The 1.6 was sort of a landmark and in production for about a dozen years.....which is a pretty long time in the world of hi-fi.

I'm a big fan of the 'thump test', but on my panels, it's a non-starter. The panel simply doesn't store that much energy.

Amp / Speaker match is all that matters.
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15308
Registered: May-04
.

An article from Monster cable; http://homepage.mac.com/tlinespeakers/vaughn/downloads/Damping-Factor.pdf

NFB is discussed in relation to DF but only in the sense that NFB can lower the amplifier's output impedance (its "Z") which increases DF into any given load. No one to one relationship is implied or stated.


That was my response at the beginning of this, Plymouth, and it will be my answer for as long as I can envision.


.
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15309
Registered: May-04
.

Can you show me any articles or White Papers which link DF to biwiring?
 

Platinum Member
Username: Plymouth

Canada

Post Number: 15008
Registered: Jan-08
Leo

I had ESS Tempest LS4 before my IMF, the tweeter used a identical technology for the tweeter, cetainly those speakers sound great then doesn't need Negative feedback vue the low inertia then the flat impedance courbe.
 

Gold Member
Username: Magfan

USA

Post Number: 1665
Registered: Oct-07
Plym,
What is the role of reactance in your scheme of things?

Just my personal opinion, but I'd rate impedance as 2nd in importantance, behind reactance and ahead of sensitivity......
 

Platinum Member
Username: Plymouth

Canada

Post Number: 15043
Registered: Jan-08
Leo

Reactance, impedance then all things that can influence the output produce by the amplifier, the final high amperage of the amplifier does not going to be influenced as well that a low amperage amplifier.
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15326
Registered: May-04
.

That's not much of an answer other than saying high current is the only way to build an amplifier in Plymouth's opinion. And certainly the designers of very successful and highly thought of amplifiers without high amperage capacity strongly disagree and have for the last 100 years. Many of you might have never read the famous quote from Paul Klipsch, "What this country needs is a good five watt amplifier". Those who agree with PWK understand minimizing reactance is a path to sonic bliss away from the brute force application of both amperage and vast sums of money. They also see the swing toward highly reactive loads in loudspeakers as a major step backwards in the pursuit of high fidelity to the original source - the music.

I've said it many times before on this forum, over the last three decades speaker designers have done their work as if their speakers do not require a real world amplifier (both in ability and in cost) to be driven with success. They are oblivious to the amplifier market and they are a major reason for those who try a tube based amplifier to find little success when the load exceeds the capacity of the amplifier. By now I'm sure the majority of forum members here on the "home audio" side know the matching of speaker to amplifier is of prime importance to any system and ignoring those requirements is the surest path to failure and wasted resources.

The oft sited Symphony Sound article,
"Tube Friendly Speakers", has been quite useful in this discussion - that is, if someone is willing to put aside their misconceptions and predetermined conclusions long enough to accept new information which contradicts what they think they "know" to be the only truth. On the other hand, if you are determined to be right and only one answer will fit how an audio sysem can be pieced together, then you are never going to see the diversity of sound which can be obtained through successfully mating the proper speaker to the proper amplifier. Sticking your head in the sand, stomping your feet and attacking any dissention or questioning while declaring how brilliant you are is not likely to gain you many fans on this forum. A forum full of people willing and eager to explore the numerous possibilites available to them. They experiment with some thought and a careful sense of questioning what they are being told and do not narrow their thinking down to believing only one method of approaching music is satisfactory.

If you take the time to read and understand the Symphony Sound article, and if you haven't already, you really should, you'll see that the reactance of the load is of prime importance in mating speaker to amplifier. We've spent quite a bit of time covering this topic; https://www.ecoustics.com/electronics/forum/home-audio/628565.html

If I can try to translate what is meant here, "Reactance, impedance then all things that can influence the output produce by the amplifier, the final high amperage of the amplifier does not going to be influenced as well that a low amperage amplifier", into a workable sentence, I would think low amperage amplifers are projected to not work well with highly reactive loads. Well, duh! no they are not. That does not mean low current amplifiers are bad or that they are unsuccessful designs. What the reality of the situation amounts to, as Symphony points out, is that such amplifiers require the proper load characteristics in speaker selection in order to be a successful pairing. If you prefer brute force as a sledgehammer to absurd loads just because you see that as the only way to build a system, then that is your perogative. But you are quite wrong to preach that everyone else must folllow your lead - particularly when it results in dangerous modifications to an amplifier. Modifications which, if we are to believe him, present 75 amps of steady state DC current hanging out in the air from an open chassis amplifier. Go out and, while holding on tightly - for as long as you can - to a wrench, short the terminals on your 60 amp car battery and see whether you think that too is a logical approach to anything. Make sure your insurance is paid up though before you try that experiment.

How we got to this point in a biwiring thread still defies my logic. Is this what we are discussing in this thread, reactance of the load to high amperage amplifiers? Not that I can see. I think leo's question is proper and insightful in this situation but, what has the answer provided us? It's interesting that Plymouth has nothing more to say about reactance than the above single sentence. He reduces the topic to a black and white/my way or no way approach to audio without at all explaining the reason for reactance in a load or how to successfully deal with the issues of reactance other than doing things his way. Possibly that stems from his experience as "a specialist in motor drive then we use the NFB in a regenerative drive to control the motor".

How many among you believe the experience with a large three phase motor running under constant load conditions at a constant voltage and current input provides you complete insight into how an amplifier/speaker circuit responds to the constantly changing dynamic demands of music being pushed through a highly reactive load? How reactive is that motor on the voltage source? How does amplifier voltage change when reproducing music? Does the motor require the power supply to respond to the instantaneous difficulties of multiples of frequencies from beyond the lower limits of audibility into the 100kHz+ range all being present at once? Does the industrial motor designer trouble themself with fundamentals and harmonics and which harmonics are musical and which are not? Does your amplifier need to respond to both loud and soft passages at the same time? Is the motor responding to the equivalent of several bass drums being struck while a quartet or possibly several dozen other instruments output the smallest of signals with harmonics which reach into the infinite? Does the license to drive mean you are an expert in how to build an automobile? You certainly can learn how those differences equate to one another but not if you refuse to acknowledge other people know things you do not. If you refuse to accept other people's opinions, is that success?

Plymouth also states, " ... I know that a powerfull drive has best result with less NFB, the inertial movement of a motor is much more signicant that a voice coil." No one denies a large three phase motor at start up draws enourmous amounts of current - at a fixed voltage and for the instant at start up after which it quickly settles to a more constant current demand at a constant voltage supply. Does Plymouth actually think this is an argument for understanding the dynamics of the amplifier/speaker circuit which might have a very large surge and then - unlike the motor - multiples of speed-of-sound start ups (and stops) to produce that tympani drum or synthesized sub-bass thwack or an explosion in a HT system? Does the motor Plymouth deals with need to respond to the slightest vibration of a single violin string at the very instant of start up for that bass note? An amplifier and speaker might find they are constantly dealing with these dynamic conditions.


So what exactly is Plymouth trying to say?


That "less NFB" is good?

For the most part that has been the stated position of the entire high end audio market, world wide for the last four decades. It was (one of) the spurs to revitalizing the low wattage, "zero" NFB SET amplifier design along with the burgeoning market for triode tubes and balanced circuits in high end audio. It was the very rejection of the high wattage, brute force approach to audio which intrigued so many listeners when they returned to direct heated tube filaments and single driver full range loudpseakers, all of which come from the very beginnings of audio. All of the thinking about such varied approaches to audio were the result of listeners thinking beyond the limitations of what was being pushed on them by the market and then finding new ways to succcesfully recreate music in their homes. If the idea of a SET, triode or class T amplifer has ever intrigued you, then you understand there can be more than one way to build an amplifier and there must be more than one way to mate that amp to revealing, transparent speakers without the need for massive crossovers which send most amplifiers into convulsions due to their severe reactance values.

If you think about it, ""Reactance, impedance then all things that can influence the output produce by the amplifier, the final high amperage of the amplifier does not going to be influenced as well that a low amperage amplifier", says absolutely nothing. Nothing other than Plymouth feels he holds the only key to how you must build your system to reflect his values. If you disagree or even question that there can only be one approach to music (not surprisingly, "music" is something Plymouth has yet to mention), you will be personally and repeatedly attacked and insulted.

Since there has been no other topic stated or reason claimed for this diversion into Plymouth's "philosophy", I can only conclude this is what he wants you to accept - his one singular way or he will not approve of your choices, just as he rejects an article from a car stereo site while posting the majority of his 15k posts on this forum to the car audio section.

The beauty of all this is, you get to decide how to proceed. You do not need to believe or accept anyone's opinion other than your own. You get to build your system any way you prefer and, should you decide a low amperage, low wattage amplifier is what you prefer, then the forum here will assist you in making the most of that selection.

At least most of us will.



.
 

Platinum Member
Username: Plymouth

Canada

Post Number: 15047
Registered: Jan-08
Do your guggle search on the good side then search why heavy current amplifier does better!

''How many among you believe the experience with a large three phase motor running under constant''

Again you are blind as usual and try to talk of what you don't know!

I was talking of regenerative DC drive, the AC motor doesnt need this kind of control due to the wave phase which control the speed, the way to contol it is raise the frequency and put more current to make that the motor not slip the phase!

A regenerative can work like a amplifier with positive output to run the motor clockwise then negative output to run unclockwise, the NFB is apply to control the motor under variant charge in regard with the encoder.

Again a false comment from you is that I'm from Car audio forum but you are wrong again, the majority of my posts are under Satellite forum.

I can add this to our conversation, my modification cost me 500$ 14 years ago, don't be surprise that most of amplifier manufacturers try to make the highest profit in their design.

An example is the solid bar to connect their capacitors which like we know does not eliminate the parasites from the AC outlet.

I'm not new in the Hi-fidelity then my experience is based on try-error not on what I can see on Google.
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15327
Registered: May-04
.

"Again a false comment from you is that I'm from Car audio forum but you are wrong again, the majority of my posts are under Satellite forum."


It's hardly a false statement, you have posts on the car stereo forums here at ecoustics. Anyone can cruise over there and find them. Why be ashamed of what you've done? The thing is, I haven't spent my time doing searches for your posts on forums other than this one. There's nothing honest about taking quotes out of context. You do, by your own admission, post on the car audio forums and talk about me behind my back on the car audio forums. And I wouldn't be surprised to find quotes from me which you took out of context from other forums and placed them on the car stereo forum.

But, despite your posting on the car audio forum, you rejected a link to calculating DF because it exists on a car audio site. Despite the fact a half dozen other sites gave the same calculation for DF.

Honesty does not seem to be your highest priority.



"Again you are blind as usual and try to talk of what you don't know!

I was talking of regenerative DC drive, the AC motor doesnt need this kind of control ..."




There is nothing in my posts that refers to you specifically dealing with AC motors. So who is being dishonest again?

The issue is whether or not experience with motors; AC, DC or any other type also provides useful insight into the function of an amplifier reproducing musical material through a reactive speaker load. Therefore, the same questions apply to how valuable your experience with motors really is to audio when you don't appear to even consider music in your posts. You look at numbers and you're satisfied what you have is good. Music doesn't play into the equation. You play with equipment to make numbers work. I prefer, and suggest others try, listening to music first and then the equipment much, much later. You have not answered the questions I posed any more than you have provided a clear topic of discussion in two threads. It doesn't really matter, as the questions were not, in the first place, aimed at you providing answers. Let's just call the rhetorical questions that require no real answer.

" It's interesting that Plymouth has nothing more to say about reactance than the above single sentence. He reduces the topic to a black and white/my way or no way approach to audio without at all explaining the reason for reactance in a load or how to successfully deal with the issues of reactance other than doing things his way. Possibly that stems from his experience as "a specialist in motor drive then we use the NFB in a regenerative drive to control the motor".

How many among you believe the experience with a large three phase motor running under constant load conditions at a constant voltage and current input provides you complete insight into how an amplifier/speaker circuit responds to the constantly changing dynamic demands of music being pushed through a highly reactive load? How reactive is that motor on the voltage source? How does amplifier voltage change when reproducing music? Does the motor require the power supply to respond to the instantaneous difficulties of multiples of frequencies from beyond the lower limits of audibility into the 100kHz+ range all being present at once? Does the industrial motor designer trouble themself with fundamentals and harmonics and which harmonics are musical and which are not? Does your amplifier need to respond to both loud and soft passages at the same time? Is the motor responding to the equivalent of several bass drums being struck while a quartet or possibly several dozen other instruments output the smallest of signals with harmonics which reach into the infinite? Does the license to drive mean you are an expert in how to build an automobile? You certainly can learn how those differences equate to one another but not if you refuse to acknowledge other people know things you do not. If you refuse to accept other people's opinions, is that success?




"I'm not new in the Hi-fidelity then my experience is based on try-error not on what I can see on Google."


You're not new to being an insulting @ss either. From what you've posted so far, a little time with Google might do you some good. If you actually accepted another opinion beyond your own, there's quite a bit to learn out there in Google Land. I doubt anyone here is ashamed of what they've learned on line and certainly not from this forum. To suggest someone should be ashamed of their on line learning because you have experience in a field totally unrelated to audio is pure arrogance on your part - another thing with which you have vast experience.


.
 

New member
Username: Superjazzyjames

Post Number: 2
Registered: Oct-10
I've heard bi-wired speakers. They sound great! Bi-amped and tri-amped are even better!
 

Platinum Member
Username: Plymouth

Canada

Post Number: 15049
Registered: Jan-08
Jan said: ''There is nothing in my posts that refers to you specifically dealing with AC motors. So who is being dishonest again?''


Jan said: ''How many among you believe the experience with a large three phase motor running under constant load conditions at a constant voltage and current input''

How a three phases motor can be DC?
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15334
Registered: May-04
.

Plymouth, I never claimed you work specifically with three phase motors. You're having the same problem here as you have had with my claims about your capacitors and hanging them outside of the amplifier chassis where there are dangerous voltages exposed. I never once said there are AC voltages on the caps. I am for being careful with AC volatges - and DC too. But I never claimed there are AC voltages on your caps. You were dishonest then and you are being dishonest now.

Please, read what has been posted ...


" Possibly that stems from his experience as "a specialist in motor drive then we use the NFB in a regenerative drive to control the motor".

How many among you believe the experiencewith a large three phase motor running under constant load conditions at a constant voltage and current input provides you complete insight into how an amplifier/speaker circuit responds to the constantly changing dynamic demands of music being pushed through a highly reactive load?

How reactive is that motor on the voltage source?

How does amplifier voltage change when reproducing music?

Does the motor require the power supply to respond to the instantaneous difficulties of multiples of frequencies from beyond the lower limits of audibility into the 100kHz+ range all being present at once?

Does the industrial motor designer trouble themself with fundamentals and harmonics and which harmonics are musical and which are not?

Does your amplifier need to respond to both loud and soft passages at the same time?

Is the motor responding to the equivalent of several bass drums being struck while a quartet or possibly several dozen other instruments output the smallest of signals with harmonics which reach into the infinite?


Does the license to drive mean you are an expert in how to build an automobile? You certainly can learn how those differences equate to one another but not if you refuse to acknowledge other people know things you do not. If you refuse to accept other people's opinions, is that success?


Plymouth also states, " ... I know that a powerfull drive has best result with less NFB, the inertial movement of a motor is much more signicant that a voice coil."

No one denies a large three phase motor at start up draws enourmous amounts of current - at a fixed voltage and for the instant at start up after which it quickly settles to a more constant current demand at a constant voltage supply.

Does Plymouth actually think this is an argument for understanding the dynamics of the amplifier/speaker circuit which might have a very large surge and then - unlike the motor - multiples of speed-of-sound start ups (and stops) to produce that tympani drum or synthesized sub-bass thwack or an explosion in a HT system?

Does the motor Plymouth deals with need to respond to the slightest vibration of a single violin string at the very instant of start up for that bass note?

An amplifier and speaker might find they are constantly dealing with these dynamic conditions.


So what exactly is Plymouth trying to say?"
}



If you think about it, ""Reactance, impedance then all things that can influence the output produce by the amplifier, the final high amperage of the amplifier does not going to be influenced as well that a low amperage amplifier", says absolutely nothing. Nothing other than Plymouth feels he holds the only key to how you must build your system to reflect his values. If you disagree or even question that there can only be one approach to music (not surprisingly, "music" is something Plymouth has yet to mention), you will be personally and repeatedly attacked and insulted."



There, I've separated out the issues of the motor, the music, the amplifier and you. That should make it simpler for you, even when it is written in English, to understand I am not claiming your experience exists with any specific sort of motor other than what you have posted; as "a specialist in motor drive then we use the NFB in a regenerative drive to control the motor". I never denied what you've posted and I've never said you have direct experience with any other sort of device.

The issue is whether experience with motors of any sort where voltage is fixed and current demand quickly settles in a near steady state condition can be expected to provide you insight into the far more complex issues of a modulated power supply (the amplifier) operating into a constantly varying reactive load when fed the dynamics of a signal as complex and intricate as is music.

Feel free to answer any of those questions about how a motor differs from an amplifier/speaker circuit when reproducing music. Though as I have said, none of those questions were intended for your answer in the first place. They require no direct answer as the answer is quite clear.

Does your experience with motors inform you of the demands of constantly varying voltage and current into a highly reactive load? If so, how?

In your work with motors are you concerned with the issues of fundamental frequencies in the sub-bass region and harmonics as they relate to a simple musical instrument? Are you concerned with which harmonics are the most musical and euphoric and which are not? How would you go about minimizing the least musical harmonics while not damaging the most musical?

Are you concerned with both high and low voltage demands at simultaneous instances? Into a reactive load?

Are you concerned with both high and low current demands at the same instant?

Are you concerned with low voltage and high current demands at 20-100kHz+ frequencies?

How do your motors respond to a musical input, Plymouth?


What is speaker "Qtc"? And how does it affect amplifier damping of the driver's motion? Do you find this same value in the motors with which you work?



Since you are so intent upon making this an issue, please, do answer those questions. Or, just say "I don't know (sh!t)."






.
 

New member
Username: Superjazzyjames

Post Number: 8
Registered: Oct-10
There is a difference between bi-WIRE and bi-AMP. Bi-wiring is using a single channel for each speaker. Many amps used to have 2 outputs for a single channel. One output ran directly to the woofer through a thick wire. The other output ran to the midrange and tweeter through a thinner wire which was wrapped around the woofer wire. This type of cable was called "time correction" cable. The reason for it is that mid & treble travel faster than bass. This set up was designed to compensate for the difference in speed. Bi-amping is using one channel of an amp for the woofer and one for the mid & tweeter. There are many advantages to bi-amping.
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15335
Registered: May-04
.

James, may I ask your age and the years of experience you have in consumer audio?
 

Platinum Member
Username: Plymouth

Canada

Post Number: 15053
Registered: Jan-08
Jan

You like post Bla Bla Bla, I was a Hi-fidelity guy long time before I was a motor drive specialist, you like arguing, I don't know you age but I'm sure that you was not been born then I played with electronic!
 

Bronze Member
Username: Superjazzyjames

Post Number: 12
Registered: Oct-10
Thank you Plymouth! Yes Jan, you are long winded, talk in circles and say things that just aren't true! Why do you ask my age and experience? So you can show me further disrespect? I'll tell you this: I'm old enough and have enough experience with audio equipment to know that you are full of crap! Ok? I'll have you know that in addition to my own experience, I've spoken to many ACTUAL experts who know well better than you what's what! I suspect Plymouth would fit in well with these individuals.
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15338
Registered: May-04
.

When did I "disrespect" you, James? You posted incorrect information. I can't change that fact. I used quotes from three different sources in an effort not to disrespect you. I explained how and why your post was incorrect. How did that show you any disrespect?


Did you too come over here from the car stereo forums?



.
 

Bronze Member
Username: Superjazzyjames

Post Number: 17
Registered: Oct-10
No Jan, I don't do car audio. I gained my knowledge from engineers first hand and experienced audiophiles who actually know what they are talking about. What I said about bi-amp vs bi-wire is absolutely correct. I gained this little nugget from a sales rep in a high end store. This store is not about to upset their customers with miss information as companies like McIntosh, B&K, B&W and other top brands would pull their merchandise in a heartbeat. As for disrespect, telling me I'm wrong when I'm clearly right. That's disrespect.
 

Gold Member
Username: Magfan

USA

Post Number: 1675
Registered: Oct-07
Plym.
I just had a further thought....or 3, about those extra caps of yours.

First, aren't you concerned about the extra series resistance? do you at least use low ESR caps? How about the same amount of capacitance divided up among more caps in parallel, to keep ESR down?

Second: How bad is the turnon surge? Do you have any speaker protection off say....a time delay relay?

Finally: how much capacitance is TOO much? Are the rule of thumb recommendations just so much gas?
 

Platinum Member
Username: Plymouth

Canada

Post Number: 15065
Registered: Jan-08
Leo

What is ESR?

I have no protection for the turnon surge or time delay! Why?

Simply because the complete amplification section use same power supply and power up equally, on many amp the first amplification stage use a different voltage which cause the bang in the speaker.

Use only Big cap is not the good way to proceed, I prefer add many 6800uf in the power supply section then put the big cap directly hooked to the driver, the big cap sound not as good because you miss midrange clarity, in the perfect world many different capacité of capacitor would be ideal but a good capacitor can be linear on the major part of frequency, that's why I use both capacity.
 

Platinum Member
Username: Plymouth

Canada

Post Number: 15066
Registered: Jan-08
Leo

I founded it!

ESR: Equivalent serie resitance.

I always use or replace by higher voltage capacitors if the space is available, for the Adcom I use 75 volts Mallory cap for about 47 volts, the cap losed the dimension with the time, sometime half of the dimension bringing breakdown of the part, the old caps was much more reliable. The layors of the capacitor are so thin that it produced a localised heat and destroy this one.
 

New member
Username: Phenderson

Post Number: 2
Registered: Oct-10
Back at the top of the thread a guy said that in biwire the lows and highs travel through different paths. Someone else said no, they only divide at the filter. That seems wrong. It's not as if the lows in the tweeter cable run off into a ditch. It seems to me that the wire from the amp to the high pass filter in the speaker carries only highs. But the amp doesn't 'see' that since the wires come together at its output. The impedance of a cable does vary with frequency which is why higher guage is preferred to avoid a high frequency rolloff. Higher guage will roll off too but at supersonic frequencies we don't hear. Cable capacitance also matters. The booklet for my BW CDM2 suggested choosing different cables for highs and lows, while warning that cable capacitance should be kept in a certain range. I don't think they believe mixing and matching cables is really a good idea; it's just a way of helping dealers sell cable, which also allows speaker makers to get away with offering less margin. I doubt that any speaker is improved by substituting anything for a single run of adequately thick OFC. But if there is a benefit to biwiring it might be because having separate wires for highs and lows prevents some intermodulation distortion from occurring in the cable. I don't know, is that physically possible and in non-trivial amounts?

BTW, I think the need for dealers to be 'cable believers' has hurt the customer relationship. Old fashioned dealers who would be too honest to promote voodoo end up at WalMart while the cynical ones make all the sales. Sane customers are driven away to make room for neurotics with trust funds. Audio becomes marginal.
 

Bronze Member
Username: Superjazzyjames

Post Number: 24
Registered: Oct-10
Well Peter, the only way to know how bi-wired speakers sound to you is to try it for yourself and see what you think.

Bi-wiring is mostly about time correction. Highs travel faster than lows, so the wire for the midrange & tweeter is longer than the one for the woofer and the mid/tweeter wire is wrapped around the woofer wire.

One thing to keep in mind is that although time correction will make the sound tighter, it may not sound natural like a concert. Remember, there is no time correction at a concert.

Also, if you have a choice between single wiring and keeping the capacitance down or bi-wiring with high capacitance, you're better off single wiring. Monster and Audio Quest both make speaker wire that they claim can correct time with a single wire.
 

Platinum Member
Username: Nuck

Post Number: 15462
Registered: Dec-04
Okay, against my better judgment (and with scotch in hand), I just have to know how treble moves faster than bass.

Please inform me.

I have a plethora of electrical properties available to me through Nasa JP Labs, the NRC and maybe the library of professional congress, but lets forget that, and see how the speed of electrons varies in any useful way to frequencies or bandwidths that are audible.

Stating that 'treble moves faster' is just fuckingstupid.

Oh, as soon as one of you clowns can add 'head of audio' in several musical theatres in Chicago to your resumes, as well as salesperson of the year in several locations, you might just want to think twice about challenging JV's experience, KIDS.

Bash at Jan's writing all you want to, but have half a brain KIDS.
 

Platinum Member
Username: Plymouth

Canada

Post Number: 15146
Registered: Jan-08
This phrase from Peter H. join my thought:

"But if there is a benefit to biwiring it might be because having separate wires for highs and lows prevents some intermodulation distortion from occurring in the cable."

Nuck

Jan is a big mouth with nothing made by him to prove what he put on table that C/P on Guggly!

How can you hear the difference of sound when you are drunk???
 

Platinum Member
Username: Nuck

Post Number: 15467
Registered: Dec-04
Because I have been listening, leaning, drinking and SHUTTING UP since I was about 10 yrs old. Well, drinking since around noon today.

Welcome to the forum Peter!
Treat the room first, avoid the nulls.

And the nuts. I have avoided calling you a troll until now, Plymouth, but there you are.
What part of accredited professional did you miss?
Musical reproduction tech for musical theatre? Several times?
This was in the 60's/70's.

If you wish to be derided moreover, then keep it up.
Like I said, you will never come close to knowing the stuff that JV has forgotten.
Pick another fight, or be COHERENT!
 

Platinum Member
Username: Plymouth

Canada

Post Number: 15148
Registered: Jan-08
"Okay, against my better judgment (and with scotch in hand), I just have to know how treble moves faster than bass."

LOL! Easy! You blind high impedance and capacitance then the result is lost of phase between High and low frequencies!
 

Platinum Member
Username: Nuck

Post Number: 15471
Registered: Dec-04
Yes, you just described a first and third order crossover(excepting the phase cross) , this has nothing to do with delivery to the speaker in single or multiple cable runs.

Stay on track man!
 

Platinum Member
Username: Plymouth

Canada

Post Number: 15150
Registered: Jan-08
You divert the subject when you are pooned like your friend Jan!
 

Platinum Member
Username: Nuck

Post Number: 15473
Registered: Dec-04
http://www.wiseacre-gardens.com/sound/trapmice.wav
 

Platinum Member
Username: Nuck

Post Number: 15474
Registered: Dec-04
troll.
 

Bronze Member
Username: Superjazzyjames

Post Number: 26
Registered: Oct-10
Nuck, before you call ANYONE stupid, kids, etc. you need to understand something. Time correction is NOT about how fast electrons flow through wires. The problem is that high frequency SOUND travels faster than low frequency sound once the electricity has been converted back into sound. Since there is no way to slow down air waves without dropping their frequency, the idea is to make the electrical signal reach the midranges and tweeters later than it does the woofer in hopes that the sound arives at your ears at the same time or at least closer together than without time correction. You know how if you suck helium out of a balloon your voice is higher pitched for a few seconds? That's because helium moves faster than air!

But if you'd rather listen to Jan and think he knows it all just because of his resume', which by the way is not necessarily achieved through knowledge, anyone with decent hearing can tune an audio system, go ahead! Let him lead you into the pit of miss information. I have friends with way more experience than Jan including electronic engineers. One such engineer showed me how the dampening factor works and what happens when it's ignored.

I'm certainly not afraid of you or Jan, I've got plenty of fight left in me for both of you! So bring it on!
 

Platinum Member
Username: Nuck

Post Number: 15475
Registered: Dec-04
Stay with the topic, Einstein.

Hey you claim to be the mad scientist tabernac, prove that you have a brain and keep one TOPIC at once, will ya?Or flood the little forum with your pablum, looking for the action that you don't find in your parents basement there.
Or just walk away as the troll that you have proven to be.
 

Bronze Member
Username: Superjazzyjames

Post Number: 28
Registered: Oct-10
Hey Nuck, ever notice that when people prove points, they make references to other topics and tie them in? I guess not. I don't live with my parents and haven't since probably before you were born and I never lived in their basement! I highly doubt you can say the same. Troll? Please go back to the sand box and let the grown ups talk ok? or sit on your daddy Jan's lap while he reads you a bed time story. Btw, Unlike you I don't need alcohol to fight.
 

Bronze Member
Username: Superjazzyjames

Post Number: 29
Registered: Oct-10
Oh btw Nuck, the subject is bi-wiring. The purpose of bi-wiring is time correction. Bi-wiring is not to be confused with bi-amping.
 

Platinum Member
Username: Plymouth

Canada

Post Number: 15158
Registered: Jan-08
superjazzyJa(me)s

They can talk of off subject!

See what happen with the thread you started:
https://www.ecoustics.com/electronics/forum/home-audio/657540.html
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 15368
Registered: May-04
.

"Back at the top of the thread a guy said that in biwire the lows and highs travel through different paths. Someone else said no, they only divide at the filter. That seems wrong"


It may seem wrong to you but what I stated is correct. The amplifier in a biwire circuit has no ability to differentiate high and low frequencies. This only occurs after the signal has passed through the (passive) filters within the speaker system.


" It seems to me that the wire from the amp to the high pass filter in the speaker carries only highs"


Same answer applies here.


"But the amp doesn't 'see' that since the wires come together at its output."


What the amp "sees" or how it is loaded comprises much of the theory of biwiring. I suggest you brush up on the topic.



"The impedance of a cable does vary with frequency which is why higher guage is preferred to avoid a high frequency rolloff."


Not'xactly.


" Higher guage will roll off too but at supersonic frequencies we don't hear."


Not at all.



" Cable capacitance also matters."


It does, but not specifically to biwiring.



" The booklet for my BW CDM2 suggested choosing different cables for highs and lows, while warning that cable capacitance should be kept in a certain range. I don't think they believe mixing and matching cables is really a good idea; it's just a way of helping dealers sell cable, which also allows speaker makers to get away with offering less margin."


"Margin" is a % of the total profit made on a sale. Your "logic" is faulty and your conclusions are the result of incorrect input.



"I doubt that any speaker is improved by substituting anything for a single run of adequately thick OFC."


You're right on this one! Until the speaker and cable are connected to an amplifier to complete a circuit, the cable reamins nothing more than wire. Wire by itself can't do sh!t.



"But if there is a benefit to biwiring it might be because having separate wires for highs and lows prevents some intermodulation distortion from occurring in the cable"


Passive components cannot generate nor do they respond to the issues which create IM, they simply pass what is input to them; http://www.goodsearch.com/search.aspx?source=goodshopbar&keywords=intermodulatio n+distortion

}}

"BTW, I think the need for dealers to be 'cable believers' has hurt the customer relationship. Old fashioned dealers who would be too honest to promote voodoo end up at WalMart while the cynical ones make all the sales. Sane customers are driven away to make room for neurotics with trust funds. Audio becomes marginal."


https://www.ecoustics.com/cgi-bin/bbs/show.pl?tpc=1&post=1907884#POST1907884


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