Do preamps affect your bass or treble power?

 

Bronze Member
Username: Jodavis

Toronto, Ontario Canada

Post Number: 22
Registered: Apr-09
Hi. I have a pair of cerwin vegas and they are big bass famous towers with a 15" woofer. I'm using the receiver as my preamp but the bass is very light. The bass is at +10. I heard people say that separate preamps (like adcom or nad) will tear the ceiling down. Do preamps affect how deep or strong your bass gets put out? Is it the power amp? Is it both? Preamps do have bass + treble controls so I assume a dedicate pre will change the whole bass and treble experience. It is definitely not my speakers so don't go there. lol.
 

Silver Member
Username: Magfan

USA

Post Number: 744
Registered: Oct-07
Check speaker relative phase.
One of 'em is connected backwards?

just a guess

15" CVs should about vibrate you to death
 

Bronze Member
Username: Jodavis

Toronto, Ontario Canada

Post Number: 23
Registered: Apr-09
No. It's not. It's probably my receiver because #1, it is a Yamaha and Yamaha has light bass. #2, it is a receiver being used as a preamp. I'm asking if a dedicated preamp makes any difference.
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 14311
Registered: May-04
.

Higher quality components produce higher quality sound. What you are looking for is not necessarily higher quality sound, you want more bass. There is a very distinct difference between what you desire and what a higher quality component will provide.

So, in your case, I would say adding a dedicated pre amp will not be the solution to your desires, most especially so if your thinking is pre amps have tone controls. Actually, most high end pre amps forgo tone controls and you already have your receiver's tone control set at +10. What more can you even expect from a pre amp with tone controls? There is only so much boost you can shove into the circuit and you've pretty much maxed out that level. You've placed the value of your entire AV system at $600, just what do you expect from $600 worth of Yamaha, an unknown power amp and a pair of Cerwin Vegas?


I will tell you throwing money at the problem when you don't know what you're doing is not the way to solve problems. But you need to realize just what $600 can get you.




Power amplifiers can affect bass response but again not in the way you are imagining. Power amplifiers can respond to a difficult speaker load, a load that is difficult due to low impedance or high phase angles in the speaker system. Your CV's have neither low impedance nor difficult to drive electrical phase angles. You don't mention which amplifier you are driving from the Yamaha but swapping to another power amplifier still wouldn't seem to be the most logical route to gain "more" bass. Higher quality power amps provide higher quality bass. You simply want more bass and a different power amp might provide some level of improvement over a cheap@ss high watt/low dollar amp but it still isn't going to do what you want.


You say, "I heard people say that separate preamps (like adcom or nad) will tear the ceiling down." Despite the poor grammar I assume you mean you have heard people say such things about pre amps. OK, which people? People who should know? Or people who want you to think they know? People who have separate pre amps? If so, why not have them loan you their pre amp and prove what they say? Or take your receiver to where their pre amp is and compare the two components side by side? Then you'll know and you won't have to depend on what you "heard".



When someone claims their desire is to "tear the ceiling down" there isn't much to imagine when you've already acquired high sensitivity speakers with 15" woofers. Leo's post was quite sensible, if your system is operating normally, we would expect 15" CV's to already be tearing down the ceiling and even more so with the bass boosted to +10. You should make certain your system is operating correctly before you begin changing components. If it is not, then fix the problem before you do anything else. Double check the polarity of the system, it's quite possible the system is wired out of pahse either by you or in one of the components. Use a battery to check for proper polarity in the speakers. Double check the connections at the amp and speakers. Polarity is the most common cause of bass problems.


If the system is wired correctly, it's somewhat difficult to imagine just how much more bass you want when you've already cranked the tone control to +10 and you're still complaining the CV's are bass shy.




Speaker placement plays a major role in how much bass you hear, as will listening position. I would first suggest you move your speakers into the corners of the room which will be the single position that provides the most bass boost. Then walk from the speaker position to your normal listening position and pay attention to the changes in bass level throughout the room. Place your chair where the bass level is highest.


If this doesn't get you the quantity of bass you desire, the next step would be to add a powered subwoofer. You already have 15" woofers which we can assume you purchased because you want even more than more bass. After you have changed the speaker/chair position you will have positioned the woofers for maximum bass boost and you'll be sitting in the highest bass peak within your room. Rooms can have as much as +40dB boost in the bass frequencies so this is not something to trifle with. If this is not sufficient, then the problem has nothing to do with the Yamaha being "bass light".

Buy a subwoofer which allows you to adjust the amount of bass boost until you manage to tear down the ceiling.


As far as the pre amp is concerned, just as you have heard the Yamaha is light in the bass and you have heard pre amps do certain things, you need to not be listening to what others say.
Get to the root of the problem and then find a solution. Learn how systems work so you don't have to depend on what you "heard" and you'll know what is correct information and what is BS.

Try another pre amp if someone says it will tear down the ceiling - if ceiling tearing is what you're after. But the subwoofer is your best route for adding more bass and IMO the pre amp is the best route for higher sound quality. I don't get from you that you are after higher quality sound, you are after more bass and the two do not always go together. What a better pre amp has to offer is not something you are likely to detect as long as you are using the CV's unless you hear it for yourself by auditioning a pre amp. I know, so don't go there. lol

.
 

Gold Member
Username: Arande2

Rattle your ... Missouri

Post Number: 2996
Registered: Dec-06
Like Jan suggested, try placing the speakers in the corners (not good for sound, but oh well) and see how that does. Also hang out near the walls if you want even more. If that doesn't cut it, it may be necessary to put the speakers together, as this will increase output from co-location. Even further, you could try them in a smaller room (maybe as an experiment) and boundary gain will alow EVEN MORE bass.

If this doesn't cut it, and if subwoofers are out of the question, the next step would be to buy an EQ and make sure you have an amp that can drive the speakers to their maximum capability, then change it to your liking.


Also, you could experiment with the tone control to see how much difference it actually makes, also see how much the cones are moving when there is 'light' bass.

As for the Yamaha, I believe it may be true they have anemic bass. I am going to do some testing..
 

Silver Member
Username: Magfan

USA

Post Number: 745
Registered: Oct-07
Is this a new setup? or new to you?

Humor me and try swapping a pair of wires to ONE speaker.

You should notice a big and immediate change in bass. One way will sound better and may give you what you want.

If that isn't it, go for overkill.
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 14313
Registered: May-04
.

"Like Jan suggested, try placing the speakers in the corners (not good for sound, but oh well) and see how that does. Also hang out near the walls if you want even more."


Sit with your back against the wall rear wall (the wall opposite the speaker location), this should provide the strongest bass reinforcement in the room.



"Even further, you could try them in a smaller room (maybe as an experiment) and boundary gain will alow EVEN MORE bass."


But also make for even deeper nulls and more reflections which could lead to other problems. Most rooms can probably deal with the frequencies of the music being played but small rooms can easily overload with bass and you'll end up with less not more bass response. More room reflections from a speaker such as the CV's will not be a good thing. I would tend to suggest you move the speakers in the room where they presently reside from either the long wall to the short wall or vice versa. Either way, keep the speakers in the corners and your seat against the rear wall.


"If this doesn't cut it, and if subwoofers are out of the question, the next step would be to buy an EQ and make sure you have an amp that can drive the speakers to their maximum capability, then change it to your liking. "


EQ's are a cheap way out and almost always bad ideas. Yeah, they boost the bass but IMO it is better to have less signal boost which can easily overdrive the amplifier and speakers (the bass control on the Yamaha is already at +10, adding another +10 isn't the best idea in my book) when playing with speaker/chair position is free and isn't going to tempt destruction of anything other than the ceiling. EQ's are almost always improperly used and will certainly be so used by someone complaining about light bass from 15" CV's.

There is no physical reason the CV's should be bass light unless the system is not physically connected as it should be, the internal wiring is mis-wired or the speakers/chair are not placed properly. (Or a woofer is already blown which wouldn't seem that unlikely.)



You did buy these speakers new, didn't you? These aren't something you got from a buddy who had blown them several times, are they?


.
 

Bronze Member
Username: Jodavis

Toronto, Ontario Canada

Post Number: 24
Registered: Apr-09
Jan. That is very informative. Speaker placement is a bit of an issue for me right now but I'll try to perfect my placement in the future. However I forgot to mention that a friend on YouTube has the SAME speakers as me. We both have the 15" woofer CV's but he is running them off a NAD preamp. His bass is much greater and you can hear it outside his house. I can't even feel the bass right next to my speaker! I think the preamp makes the difference since we both have the same speakers. No?
 

Platinum Member
Username: Nuck

Post Number: 14329
Registered: Dec-04
Julien, making bass is the job of the room and the amp, not a preamp. If the Yammy is maxed out, then something else is wrong.
I have herd many CV speakers, and never have I asked for more bass than the flat setting.
Room or connections, or both.
 

Gold Member
Username: Arande2

Rattle your ... Missouri

Post Number: 2997
Registered: Dec-06
Jan, I hope you know I was not making practical recommendations :-)

It is also true I got something from what you said. Small rooms, if made of concrete, and air-tight, I'm sure would handle the bass..? Or is that not the reason why it wouldn't work out very well?
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 14314
Registered: May-04
.


"Speaker placement is a bit of an issue for me right now but I'll try to perfect my placement in the future. However I forgot to mention that a friend on YouTube has the SAME speakers as me. We both have the 15" woofer CV's but he is running them off a NAD preamp. His bass is much greater and you can hear it outside his house. I can't even feel the bass right next to my speaker! I think the preamp makes the difference since we both have the same speakers. No?"


No.

Placement is as much as 90% of speaker sound and virtually all of bass response. If you cannot situate your speakers and your chair properly, you will never have top notch bass response - though I doubt you and I would agree on what is top notch bass response. Surely you have two corners and a back wall you can use.


I see other issues with your post however. You cannot make any comparisons against something posted on YouTube. Maybe that isn't what you meant but I have no idea how you are making any comparison to his set up. You say he is running his speakers off a NAD pre amp, fine, but he must have more running his speakers than a pre amp since a pre amp has no wattage component. Do you understand the differences between a pre amp and a power amplifier? What power amps are you and your friend using? Why did you decide to run your Yamaha as a pre amp only? I'm unaware fo any Yamaha receivers that would have pre amp outputs and sell for a system price of $600 with the CV's. If you are using your receiver strictly as a pre amp, you must have a power amp; which one?

As to feeling the bass when you are standing right next to your speakers, no pre amp should make that sort of difference in bass response. Maybe you and I are talking about different things? Just how much bass does your system produce? Would your father think your speakers are bass light? Or are we talking headbanger "light bass"? Light bass compared to, what? the club you go to?


Have you heard your pair of speakers produce bass response you would call adequate? Not the same model speakers on YouTube but your pair of speakers?




Rooms make all the difference in bass response, if you cannot "feel" the bass standing next to your speakers I would first put the differences between your system and the YouTube system down to different rooms. Next, I would tell you in my experience and to my taste I have never been close enough to a CV that I wanted to feel more bass or get any closer to the speaker. This sort of tells me your speakers are not operating as they should.


So, we're back to making certain the speakers are wired correctly. Do you know how to use a battery to check for polarity? Have you done so? Do you know how to ensure your cables are wired for correct polarity? Have you double checked those cables for proper wiring? You claim to have eight years of experience in the AV industry. Was this in car stereo? If not, where? Doing what?



Are these speakers you purchased as new? I ask questions because I need to have answers before I can get you any further along. If you ignore my questions, then I have no reason to be here. Quite honestly, I don't care whether you can feel the bass. If I ask a question, you need to supply an answer. Go back and look at what I've asked and give some responses.


My intial impression here taking into account what you just posted is your system is either wired incorrectly or you have speakers that are not working correctly. Fill me in.


.
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 14315
Registered: May-04
.

"It is also true I got something from what you said. Small rooms, if made of concrete, and air-tight, I'm sure would handle the bass..? Or is that not the reason why it wouldn't work out very well?"


To begin with rooms made of concrete would need to be sealed quite well to be air tight. I know of nothing in domestic construction that is built to be absolutely air tight. However, assuming you managed to build a concrete room that was air tight, the response would still depend on the dimensions of the room against the lowest frequency you were trying to reproduce - not that much different than an acoustic suspension enclosure except we are dealing only with a back wave in the speaker cabinet. None the less, pressure waves react the same whether they come from the front, back or both sides of the driver. They "resonate" at specific frequencies related to the dimensions of the enclosure and those fluctuations in pressure must be damped or allowed to diminish in some fashion.

Bass pressure waves must have sufficient room to propogate, normally if you can get one quarter to one third of the longest wave length as your longest room dimension, the bass wave will have a fighting chance of sounding not that bad depending on the other two dimensions. If you cannot develop at least that 1/4-1/3 wavelength in your room in at least one dimension, then the standing waves will quickly begin to overwhelm all response until a wavelength and a dimension which allows proper dissipation is reached. Since standing waves also affect the harmonics of the null frequency, this nulling effect continues well beyond the point were frequency and dimensions work themself out. Therefore, the frequency response of small rooms is almost always much worse peak to null than any larger room would be.

To say this differently, a small enclosure when pressurized will tend towards less bass (and certainly less smooth bass response) at a higher cutoff frequency than a larger enclosure due to the enclosure dimensions. There is no substitute for a larger room. Absorption of some sort or a negative pressure resulting from Helmholtz Resonators within the room can make the room appear acoustically larger much like acoustic stuffing inside a speaker enclosure makes the driver see a virtually larger enclosure. But, still, size matters and big is always better than small when it comes to smooth, deep bass response.



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Platinum Member
Username: Nuck

Post Number: 14331
Registered: Dec-04
Julien, we can fix this easy with more info.
 

Bronze Member
Username: Jodavis

Toronto, Ontario Canada

Post Number: 25
Registered: Apr-09
Ok. I did the polarity check with a 9v. battery. the results were good. The cone moves out(towards me) rather than in. So that's done. Boom. Now, you guys wanted to know my set-up. Yes, the Yamaha receiver is being used as my preamp. Ontop of that sits my power amp. It is a 1000 watt (no real watts here) Pyramid amp. It is being used temporarily.
 

Platinum Member
Username: Nuck

Post Number: 14335
Registered: Dec-04
Now you should reverse the polarity of yur speaker leads on both sides.
The gear can (and usually does) reverse polarity several times.
Just reverse them and try, no damage will be done.
You can swap at either end, but both the same. Note speaker wire colours.
 

Bronze Member
Username: Jodavis

Toronto, Ontario Canada

Post Number: 26
Registered: Apr-09
Wait. I thought if the speaker cone moves out, your polarity is fine. Mine moved out. Not in.
 

Gold Member
Username: Arande2

Rattle your ... Missouri

Post Number: 2999
Registered: Dec-06
In a small room, would bass resonate longer? I think that is a silly question, as you just explained, so bass at the modes would resonate for a while..

I always thought bass sounds better in a large room.. especially the LOW stuff.. All I'm getting here is wave mode > pressure mode... ? Explains why my headphones nor a car seems to do it right.. Yet I 'knew' this all along, in a sense.

On the speaker polarity, make sure to quintuple check. I thought I did my wiring right on a driver and it turns out I still switched the wires on the end I was not concentrating on. I think you are fine though..

It could be the room. For some reason, my room seems to SUCK out bass response badly.
 

Platinum Member
Username: Nuck

Post Number: 14336
Registered: Dec-04
Julie, I told you not to ask. Just try it.
 

Platinum Member
Username: Nuck

Post Number: 14337
Registered: Dec-04
have a free 'n' sorry.
 

Platinum Member
Username: Nuck

Post Number: 14338
Registered: Dec-04
stupid edit function
 

Silver Member
Username: Magfan

USA

Post Number: 748
Registered: Oct-07
Nuck.....shame. Reverse leads on one speaker only! And only at either the speaker or receiver end. Relative phase, not absolute is at issue.
The 9v battery test? Use a battery tester.

In or out doesn't matter. What matters is if BOTH go out or in with the same signal polarity.
From your first post, it sounded like out of phase bass. This is the worst and easily checked by just swapping a pair of wires on either speaker at either receiver or speaker end.

Please, just try it. It is a classic mistake and easily done, easy to hear and just as easy to correct. If this is it, you will never get burned by it again.
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 14317
Registered: May-04
.

"In a small room, would bass resonate longer? I think that is a silly question, as you just explained, so bass at the modes would resonate for a while.. "


The problem comes from the use of the term "resonate" which is not what we are discussing in this case.

Speaker enclosures are termed "resonant chambers" but most people tend to confuse "resonant" with "resonate". I'm not sure I can adequately explain the differences but the idea of "resonating" brings to mind panels or objects set in motion by pressure waves to produce a sound whose frequency is determined by the dimensions of the panel - a "resonating" speaker cabinet will typically have different resonant frequencies on different panels.


The speaker enclosure is a "resonant" chamber in that pressure waves change from positive to negative pressure at frequencies produced by the driver responding to an incoming signal. The "resonant" frequency of the chamber is determined by the volume of the enclosure and not so much any one or two dimensions. So, while a speaker enclosure might have panels which "resonate" due to inadequate stiffness or damping, the sound they produce has nothing to do with the "resonant" frequency of the chamber's volume. Now take that explanation and apply it to the room which becomes the "resonant" chamber enclosing the speaker system(s).


Do you see your answer in there, Andre?


When we are discussing bass response the bass will not "resonate" for a longer period of time. The room becomes the resonant chamber and therefore the volume of the room determines the resonant frequencies of the enclosure - not the resonating frequencies of various walls or objects within the room. Since most rooms share roughly similar dimensions for height at least we can talk about the other two dimensions in terms of how we calculate standing waves and their strength. Put a speaker in a standard room with 8-10' ceilings, however, and then in a modern "great" room or an auditorium with 25-30' ceilings and things change. It is still down to room volume and specific dimensions that determine the frequencies and strength of standing waves and room nodes but just as in speaker enclosure construction or vent calculations volume must work with dimensions which, of course, go into determining the volume of the enclosure. Consider a speaker port where changing the length alters the port volume which in turn shifts the resonant frequency of the system. As in speaker enclosure design, change one value and you alter the other two. In the end, though, the enclosure/room is being pressurized at vastly different frequencies when you play music and the volume of air inside the room is "resonant" as the waves go from positive to negative.

Does that makes sense?


As to pressure waves "resonating" longer in a small room, yes and no. Change "resonating" to "reflecting" and you'll have the answer to this question. Since the dimensions of a small room are closer together there isn't the distance between surfaces which would allow the normal dissipation or roll out of any signal with distance; double the distance = -6db signal strength. All frequencies then reflect more and have more strength at each reflection point which gives small rooms strong echoes at mid to high frequencies and deeper peaks and nulls in the bass as longer waves meet each other at closer distances. All of this adds up to smaller rooms having more dramatic shifts in frequency response top to bottom due to comb filtering and more signal smear due to short wavelength reflections which would impact soundstaging. In a smaller room moving your head a few inches will make for far more exagerated shifts in perception than would occur in a larger room.


Hope that helps.



.
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 14318
Registered: May-04
.

"Relative phase, not absolute is at issue."

Right, in the first place "absolute phase" is very likely not going to be achievable with most modern multi-mic, multi-channel mixing console recordings.

"Relative phase" determines whether a stereo pair of woofers move in unison or in opposition to each other to either a positive or negative going signal.

While absolute phase might matter (slightly) to the audiophile with a system of sufficient transparency (and one that states whether a single component inverts phase) and recordings where attention was paid to such things, it is whether the drivers move together or separately that will determine perceived compression and rarefaction within your ear canal. Or, whether the ear perceives nothing due to cancellation of the signal by opposing forces.


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Platinum Member
Username: Nuck

Post Number: 14344
Registered: Dec-04
More than once a speaker has been made wired backwards inside.
Julien, did you try the swap?
 

Silver Member
Username: Magfan

USA

Post Number: 752
Registered: Oct-07
I've tried absolute phase on AT LEAST 20+ recordings. It made a difference on exactly 1, a recording of solo Classical Guitar.
Rock? nope Orchestral? not hardly soundtrack? negative Gregorian Chant? who listens to that?
 

Platinum Member
Username: Nuck

Post Number: 14352
Registered: Dec-04
Gregorians?

Hey, you asked.
 

Silver Member
Username: Magfan

USA

Post Number: 753
Registered: Oct-07
These guys ROCK.
http://en.wikipedia.org/wiki/Gregorian_chant
http://www.youtube.com/watch?v=YYnzL5IuK3M
 

Gold Member
Username: Arande2

Rattle your ... Missouri

Post Number: 3001
Registered: Dec-06
I suppose what you said somewhat makes sense, Jan..

The main difficulty I have is that I don't think my original question was asked correctly...

Decay time of a frequency is more related to absorption? So wouldn't room size have no effect at all? I mean, a large room will have a longer time before an echo... A small room just has smear problems, not necessarily 'decay' problems.
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 14331
Registered: May-04
.

I'm not sure what you're asking, Andre.



"Decay time of a frequency is more related to absorption?"

I suppose the correct answer to that question is, no.

Signals decay at set rates, conditions can alter those rates. Signals decay due to friction, what is really a conversion to heat. Travelling through "air" the rate of decay is variable with the frequency - higher, smaller wavelengths being slightly more quickly dissipated than lower, longer waves and their rate of decay will also vary with the density of the atmosphere - high humidity being more dense and therefore creating more friction that dry air.

This is generally lumped into the quick equation of "2 X distance = minus 6dB" for shorthand operations calculating how much you will loose as you move away from the sound source. For example, most speaker sensitivity specs are quoted at 1 meter away from the source. If you move to double that distance away from the source, you've lowered the precieved level by -6dB. Think about that next time you're at a concert listening 150' away from those 110db speakers hanging from the rafters!



"Absorption" is nothing more than the introduction of artificial friction devices. Fiberglass absorbs sound waves by way of heat caused by friction. Energy cannot be destroyed, only converted to another form of energy is a "law" which almost all other theories follow. The more friction you can create - thicker absorption devices or passing a reflected wave through the material a second or third time - the more decay you can introduce in the same distance travelled by the wavefront. This is how the majority of room treatment devices operate and explains why placing absorption devices directly against the wall is far less effective than locating the device slightly away from the reflective surface of the wall and benefitting from the secondary passthrough of the wavefront.

One alternative to the absorption technique is cancellation which can easily be done - with a few calculations and some handiwork - by employing Helmholtz Resonators The basic problem with either method is just how broadband is the resulting effect. Helmholtz Resonators tend to be very narrow band and affect only (roughly) single frequencies when used as room devices. Absorption devices however tend towards being quite broadband in their effect and can often remove too much of the frequency bandwidth when you only wish to affect a narrow band of problematic frequencies thus leaving the room sounding too dry and the music too lifeless and mechanical.



"So wouldn't room size have no effect at all?"


Obviously, it does. Using the concept of signal dissipation by distance the small room allows for less lowering of the signal strength before the pressure wave contacts a constraining/reflective surface which in the case of long wave lengths found in bass frequencies will send the wave front back on itself. Now you have positive and negative going wave fronts meeting somewhere in the room and cancelling each other at some locations within the room and adding to each other in another location in the room - the basic idea of how room nodes develop and how standing waves (cancellations) and peaks are multiplied in intensity.

If there is more distance between the reflective surfaces, there is more frictional dissipation of the wavefront and the resulting additions and cancellations are lessened. That gives the larger room the benefit of smoother response when compared to the smaller room even if both are using the same type and amount of absortive devices. The purpose of adding absorptive devices to a room is to "fool" the room into acting as if it were larger the same way adding acoustic stuffing (absorption) to a speaker cabinet creates a virtual larger enclosure.

If you were designing a sealed speaker system, your calculations would show that there is a rather critical volume for the desired bass response, too small and you raise the cutoff frequency while too large and you also raise the cutoff frequency. Stuffing the enclosure can alter those volume calculations and until TS parameters were fully understood and implemented the common way to build an acoustic suspension system was to calculate the overall volume of the enclosure for the F3 desired then stuff the cabinet until you arrived at the best (normally lowest) single impedance hump. Many sealed systems are still being built in not too different a fashion as calculations are not always sufficient to achieve desired results in the real world.



"I mean, a large room will have a longer time before an echo... A small room just has smear problems, not necessarily 'decay' problems."


Smear problems are decay problems. Each individual reflection is stronger in level in the small room simply because the wavefront has not travelled the distance required to lower its level. The wavefront can only dissipiate with friction - remember? energy cannot be destroyed - either by travelling "X" distance to reach "Y" level or by the introduction of absorption/canellation devices. Until the signal reaches the same distance travelled to achieve, say, -12dB rollout the small room's peaks will be higher and the nulls will be deeper that a larger room where the wavefront naturally falls off due to distance travelled.


Make sense?




.
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 14332
Registered: May-04
.

Those are answers that should appeal to the calculations you've been performing lately, Andre. The real answers, however, are not always found in calculations. "Sound" as we know it results from the compression and rarefaction of the pressure wave(s) acting on our eardrums. That is where the explanation begins and for too many who want simple on paper answers it is also where it ends. Such shortsightedness leaves out all the intricate operations of the mechanisms which exist between your eardrum and your brain where the real information is processed (along with tens of thousands of other simultaneous stimuli) and "perception" takes place. As we understand more about the workings of our brain and how it influences our perception we are also moving away from many of the "traditional" answers to problems in acoustics. While just scratching the surface of comprehension we have a better idea why totally passive devices which do not at all affect the signal can lead us to a more complete and articulated perception of what is occurring within the room.


Once such device is the Shakti Happographic Room Lens. A rather interesting device, even after years in development the designer readily admits he cannot fully explain just how the device functions - but function it does. While devices like the Shakti are poopoo'd by the numbers folk Shakti has also designed other passive (and active) devices that defy "known" realities. This review; http://www.6moons.com/audioreviews/shakti/hallograph.html also mentions the Shakti Stone, a device which is as effective on audio components as it has proven to be in automotive applications. Such devices bring out the howls of "placebo" along with "audiophool" and much worse from the on paper numbers crunchers who simply ignore the proof of devices such as the Stone.

Obviously, Andre, I have left on paper calculations where I believe they should belong and have embraced something more than a TI calculator for answers. That doesn't mean I ignore the numbers, I just use them where I think they are best implemented. It's up to you to decide just how you will react as you travel along the path to audio Nirvanna - or something akin to just good sound. I can only tell you numbers, IMO, do not tel us everything and what we know today is likely to be replaced tomorrow.


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Platinum Member
Username: Nuck

Post Number: 14362
Registered: Dec-04
http://www.vintagecalculators.com/html/ti_cal-tech1.html
 

Silver Member
Username: Magfan

USA

Post Number: 756
Registered: Oct-07
One measure of room 'liveness' is its RT60 for which calculators are available: to wit:
http://www.csgnetwork.com/acousticreverbdelaycalc.html

There are many more calculators all using the same, basic formula.

also, from WIKI, where it all started.
http://en.wikipedia.org/wiki/Reverberation

An Anachoic chamber should have an RT60 of near 0.
 

Gold Member
Username: Arande2

Rattle your ... Missouri

Post Number: 3002
Registered: Dec-06
Jan, your first answer is correct, I believe.. but I think it is 'not quite' there in terms of relating to my question. The reason why is because what I am meaning to ask is not what you answer because I don't know how to get across what I mean.. I am using the wrong words..

I can agree with your second post.. I do believe the calculations we use today are mostly approximations and the other things we don't know yet.. some things we may never know as our brains just can't perceive it..

I would like to get more experience just listening to the same speakers in different rooms/environments... An anechoic chamber would be interesting..
 

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 14336
Registered: May-04
.

"Jan, your first answer is correct, I believe.. "



My first answer is corrrect, Andre.


.
 

New member
Username: Esowden

Richmond, KY

Post Number: 1
Registered: Jan-10
Julien - the problem could be your power amp. The Pyramid brand amps are a bit iffy as far as actual power and frequency response.

How do the speakers sound when you drive them with the Yamaha alone?

As sensitive as the speakers are (assuming they are the VE-15F series) a modest receiver/amp shouldn't have any problem driving them in the manner you're expecting.

Another thing to look at is the source of the music. Are you using a CD, iPod or other source for music? Either of these can have a dramatic effect on bass response.

Hang in there - we'll help you figure it all out.
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