Looking for a system with high db

 

New member
Username: Flame_q_69

Gregory, M.I. U.S.

Post Number: 5
Registered: Apr-04
i have about $700 to spend on a new system, and i am tried of having an ok system...i have 2 12q's right now and i am running 550 to each right now...can anyone tell me about a new system that will reach around 140 db.
 

Anonymous
 
you could buy 3 adire shivas and a jbl BP 1200.1 amp, power one of the shivas with your current amp and the other two with the jbl, in any box i assume you could reach 140db.. anyways the shivas are 650 rms and are on back order until May 10
the total of subs and amp should be close or under 700
 

New member
Username: Santaclaw

Tromso, Troms Norway

Post Number: 13
Registered: Jan-04
If i vere you, i'd buy myself a brand new 15" (15d2) Cerwin Vega Stroker (this year's modell) and a MA-Audio 4400w amp(Model: HK-802SX), it wil cost you around 700$

I'm using this setup myself, and i'm hitting around 154 db....

Btw, by a LOT of capacitors....
 

Cron
Unregistered guest
capacitors don't do anything they are a waste!
 

New member
Username: Hostage

Post Number: 3
Registered: Apr-04
then what should people do get more powerfull alternators??
 

Bronze Member
Username: Santaclaw

Tromso, Troms Norway

Post Number: 14
Registered: Jan-04
I suppose you KNOW this ??

I'll awnser that question for you.

No, you don't.


Capacitors are the only thing that helps you when your engine is running, to stiffen the bass, and give a lot of surge power...

1-3 xtra batteries will also stiffen the bass, but won't have the same effect as a capacitor wil.
 

Bronze Member
Username: Santaclaw

Tromso, Troms Norway

Post Number: 15
Registered: Jan-04
Yes, besides a capacitor, a new an larger alternator is the way to go :-)
 

Gold Member
Username: Glasswolf

NorthWest, Michigan USA

Post Number: 2534
Registered: Dec-03
Andreas, actually you're incorrect.
capacitors are a gimmick thta mask symptoms, but solve nothing.
what you need is an alternator rated to supply the current required by both the car itself and the audio system at full output.

Here's more information on capacitors that I wrote for a FAQ some time ago:
http://p079.ezboard.com/fcaraudiotalkfrm27.showMessage?topicID=10.topic
and on charging systems:
http://p079.ezboard.com/fcaraudiotalkfrm27.showMessage?topicID=23.topic

Now as for what I do or don't know, before you tell me I don't know anything, like you did the last user, I have pretty solid credentials in this field, and have for over a decade.

 

Cron
Unregistered guest
Yep, Alternator is the way to go. Caps do nothing.
 

Bronze Member
Username: Santaclaw

Tromso, Troms Norway

Post Number: 16
Registered: Jan-04
Oh.. am I

I belive we've had a similar discussion once before....

GlassWolf...

Most people that buy a Car Stereo, complete with a huge sub-woofer, and a giant amp, does NOT listen to a continious 45 hz bass test, all day everyday...

Most people listen to many different kinds of music, Like : dance\trance\techno\death\heavy metal\rock.

As you know all electric devices create a voltage surge when they are switched on, it doesn't matter if it's a lightbulb, or an amplifier.

Depending on the type of cabeling you have, size, lenght or the material used, and of course the amount of ampage the amplifyer draws this voltage surge wil increase\decrease.

As you say, the alternator delivers all the voltage\current while the engine is running...

But, this is only correct if the power consumers draw a constant amount of current...

So in a way you ARE incorrect when you say that an extra battery or capacitor won't help.

A regular "analog" alternator's charge regulator use a few seconds to adapt to new power consumers.

This you can messure with your voltmeter, hook it up to your battery, and start the engine, rev the engine to about 2500 rpm, and swith on a large powerconsumer, like a rear window heater, or a seat heater.

As you see, in the second you swith on the consumer, the voltage wil drop, but after a few seconds it wil increase again...

Try the same with a capacitor attached...

Let's say you have a consumer that draws 500w.

If you connect a 0.5 fharad capacitor, the voltage wil still drop, but it wil not drop nowhere near what it would with no capacitor connected, and because the voltage hasn't droped as much as it would if there was no capacitor, the charge regulator doesn't have to compensate that much, and wil react faster.

By adding a capacitor, you WIL get a punchier bass, but you won't nessaseraly be able to messure it in db's....

"what you need is an alternator rated to supply the current required by both the car itself and the audio system at full output"

Could not agree more, but let's say my amp draws 360 amps....

Find me an alternator that delivers even near that amount of current...

The more current your amplifyer draws, the larger the voltage drop wil be.. so the more fharad you wil need to compensate...

0.5 fharad per 500w.

A digital voltage regulator greatly increases the sound quality\spl level, because it responds quiker to voltage dropps.

I hope I got something thru the langauge barrier..
 

Silver Member
Username: Its_bacon12

Post Number: 517
Registered: Dec-03
hehe you misspelled WILL about 46518094568914976 times

"Find me an alternator that delivers even near that amount of current... "

you dont necessarilly need just one alternator.... dual 215A alternators could do the trick :-)
 

Anonymous
 
bacon how bout you get out of glasswolfs @ss already
 

Bronze Member
Username: Santaclaw

Tromso, Troms Norway

Post Number: 17
Registered: Jan-04
Bacon... ok.

Will :-)


Find me some room in my 1991 model Opel Kadett 2.0i - 16v... with my supercharger, Ac, Servo, intercooler hoses +++ taking up half the engine bay, not to mention my 270 amp stinger alternator, I simply don't have the room...

I guess I could mount it over by the right headlight, but I would certanly need a lot of fan belts and pullies ++

 

Silver Member
Username: Its_bacon12

Post Number: 521
Registered: Dec-03
rofl yes you would but like im saying - it can be done.....so you dont necessarilly have to look for one alternator

btw...nice mods hehe :-) im likin it

and anonymous, r u retarded..? just answer me that
 

Gold Member
Username: Glasswolf

NorthWest, Michigan USA

Post Number: 2580
Registered: Dec-03
"As you say, the alternator delivers all the voltage\current while the engine is running...
But, this is only correct if the power consumers draw a constant amount of current..."

If more CURRENT (not voltage) is needed, the alternator will supply that, right up to the limits of it's ability to produce that current.
After that, the car's battery will try to stablize the voltage rails, and that won't last long, as once the battery is depleted, the voltage rails will continue to sag. The capacitor will only hold about 30 seconds of charge, and once that's depleted, and the alternator is already maxed out, the cap won't be able to recharge.. making it useless.

Unless you're an electrical engineer too, please don't try lecturing me on electrical principles.
here's more information on how the charging system of a car works:
http://www.bcae1.com/charging.htm

"A regular "analog" alternator's charge regulator use a few seconds to adapt to new power consumers."

analog?
alternators ALL produce AC voltage by having the rotor coils spun around the stator coils.
After that, the AC voltage is run through a bridge rectifier circuit to change the voltage to DC, and then on to the voltage regulator which smooths out the voltage (now DC) to a steady 14.4 volts or whatever you happen to have it set to. It's that simple. The ONLY lag involved is the propagation involved in the circuitry itself, and that can be measured at the most, in milliseconds.
The point is however, that a capacitor still will not replace the need for a sufficient alternator.

"As you see, in the second you swith on the consumer, the voltage wil drop, but after a few seconds it wil increase again..."

then you have a weak alternator. above idle, in a properly designed system, there won't be a drop.
The voltage rails will stay rock solid, and current will be supplied as needed. As long as you can keep the voltage rails above 12.5 you're fine though, even if the rails do sag slightly at times. The probelms occur when the voltage rails sag below 12V, and stay there.. which is when you see the dimming lights, the distortion, the spark misfires, etc.. as long as we can avoid these problems, we can disagree all we want about the piddly stuff.

"Could not agree more, but let's say my amp draws 360 amps....
Find me an alternator that delivers even near that amount of current..."

sure
stinger
ohio generator
wrangler
or, run two alternators.
If you're drawing 360A of current, that's over 3Kwatts of power for amplifiers. You're going to have to rebuild the entire charging system from the ground up for that sort of load anyway.
At least if you plan to have it work properly to it's full potential.

Ok I don't really see this going anywhere from here.. there's been plenty of information and resources and references supplied for anyone interested, so I'm going to pretty much end this before it turns into another freakishly long thread.

 

Bronze Member
Username: Santaclaw

Tromso, Troms Norway

Post Number: 18
Registered: Jan-04
Ok, I will continue to expand my stereo setup with more caps, whether you like it or not...

When my amp, rated at 4000w, delivers what it's capable of with my current setup to my 15 inch stroker, I can hear the difrence between 3 fharad, and 6 fharad...

Just to sumarise my mods to the charging system...

270 amp stinger alternator.

6 x 0.5 fharad capasitors

400$ digital "Harrald Revne" Charge regulator, Features :

Fully digital electronic charge regulator, with built in foto sensor to increase the voltage when it's dark outside witch in turn provide "better" headlights... It also "senses" the current status of my batteries changing the voltage output to compensate.. Remote voltage override, I can set the voltage to anyting from 12.5v to 15v from inside the car.

Before :

when doing db tests, my voltage would drop from 14.4 to as low as 12v, even though all my wiers was solderd, and all ground connections was solderd to bolts welded into the car's chassis and using a minimum of 25mm2 cabeling, (35 mm2 from one of the rear batteries to the amp) 25mm2 cabels from the alternator to the battery, and 25mm2 to the rear batteri.

With the new regulator if my voltage is set to 15v, it STAYS at 15v, almost no matter what...

"If you're drawing 360A of current, that's over 3Kwatts of power for amplifiers. You're going to have to rebuild the entire charging system from the ground up for that sort of load "

In other words, been there, done that..

A capacitor helps.

Heh..

If you can't hear the diffrence, get better ears. :P
 

Gold Member
Username: Glasswolf

NorthWest, Michigan USA

Post Number: 2613
Registered: Dec-03
my hearing is perfect, thanks.
and, on top of that I'm an electrical engineer, not a kid who buys into advertising hype.
I don't really care what you do to your car, or what you think to be honest.
I'm just preventing you from feeding other people your BS.
have a nice day :-)
 

Gold Member
Username: Glasswolf

NorthWest, Michigan USA

Post Number: 2615
Registered: Dec-03
Oh, I just noticed, you're 21 years old.
that means you're still young enough to know everything, while I, an EE and MECP master certified installer with over a decade of *real* experience, and plenty of IASCA pro circuit wins to back that up, apparently don't know what I'm talking about.

ok, you win!

I'm starting my new career in basket weaking Monday, first thing.
 

Bronze Member
Username: Panache

Brenham, TX US

Post Number: 32
Registered: Apr-04
How do you measure your db? Id love to know mine.

 

Bronze Member
Username: Santaclaw

Tromso, Troms Norway

Post Number: 19
Registered: Jan-04
You use GlassWolf's "perfect" hearing, sure to give a 0.1 db accurate messurement.
:-)

You say the alternator is incapable of having voltage dropps as long as the amplifyer draws less the the alternators rated current output ?

Since you are an electrical engineer, I guess you've scoped an amp while playing different kind's of music, and during different volumes ???

I also guess you saw that during most types of music, except for db-test tracks, the amp's input fluktuates alot, and creates voltage drops\highs, due too induktive reactions in the cabeling ??
(extreamly badly put)

The longer the distanse between the amp and the battery\generator, the higher and more seveere theese spikes and drops wil be...

This you know.

As you know, the cap is usualy rated 20v

This means that if your car is switched of, the cap wil be charged to 12v or what ever your batteri is charged to.

if you switch the engine on, and the alternator outputs 14.4v, the cap is charged to 14.4v.

So, if you place a cap near the amp, and have a 4 meter wire from the alternator to the cap\amp the cap wil effectivly level out most voltage drops, or at least limit their effect.
 

Gold Member
Username: Glasswolf

NorthWest, Michigan USA

Post Number: 2623
Registered: Dec-03
you measure SPL using an RTA or sound meter.
most higher end audio shops will have one, or go to a competition event and get metered there.
There's usually a small fee to get it done.
SPL is metered at the dash.

'perfect' hearing according to the AMA, and hearing tests performed by a licensed medical doctor, yes. No measureable loss. I take care of my hearing.

yes, I've had more amps than I can count on a scope. The shop where I used to work was also an authorized repair center for most of the better companies.

the inductance of the cables doesn't have any real efect on the input stage of the amplifier when the line voltage is balanced to the input stage of teh amplifier using the input sensitivity properly, and when the amp is built well, meaning it has a *good* power supply, rated for a minimum of three times teh amplifier's maximum output. This is one reasons cheaper amplifiers are as cheap as they are, and what differentiates them from good amps. The power supply. dual toroidal transformers, use of MOSFETs in the input stage, and so forth. This has a large effect on the damping factor of the amplifier as well, which is the amp's ability to react to the inductance of the drivers themselves.

You apparently didn't read the article I wrote on capacitors, which I supplied for you in the above URL.
I've already noted that a capacitor will reduce transient response times for an amplifier, which you did a nice job of explaining.
What the capacitor will NOT do, which has been my contension all along, is take the place of a sufficiently rated alternator. A capacitor isn't a battery, and it isn't an alternator. Caps don't create or produce current. They only store it, then quickly release what they've stored, at which time they need to be recharged at a relatively much slower rate than they discharged.
For the capacitor to recharge, the voltage rails need to be stiff, to, as you just noted, bring the capacitor charge up to that of the voltage rails, which above idle should be let's say 14.4VDC.
if the alternator is weak, voltage rails sag, you get maybe 10 volts, and your cap is useless once its discharged to keep the voltage rails stiff.
does this really not make sense to you at all?
 

Bronze Member
Username: Santaclaw

Tromso, Troms Norway

Post Number: 20
Registered: Jan-04
Of course it does...

I just like to ask questions with wrong awnsers, so I get good explenations...

I failed the last time I tryed this on you...

As you might have suspected, I compete in Db drags..

And because almost no Db dragging test sequences lasts for more then MAX 30 seconds, the caps DO help...

Especialy if your alternator is 90 amp's to smal..

I actualy have 4 x 15 fharad caps connected in paralell, and less then 10 cm from the amp I have to 3x0.5 fharad banks....

It takes more than 30 seconds to drain 66 fharad at 90 amp...

Before the 30 second crank, I use a digital ampmeter (a plyer you clamp over a cable to messure electron flow), this is a LCD display placed so I can see it from outside the car, after fast ideling for 15 seconds I see no negative flow(perhaps 10 amp) to the capacitor banks\rear batteries....

During the 30 second test, it climbs to about 347 amps @ 14.8v (alternator is rated @ 15v with the digital charge regulator) and after the test, the caps/rear batteries are charged with almost 250 amps @ 15.1v... heh...

the 25mm2 wire coming from the front battery is about skin temprature.......

Annyways, GlassWolf.. Thnx for the info.
 

Gold Member
Username: Glasswolf

NorthWest, Michigan USA

Post Number: 2641
Registered: Dec-03
yeah a clamp-on ammeter. I have a couple flukes like that.
handy things for working on high current AC lines in a house too, like HVAC systems.

yes for burping I could see where the short discharge would help, since after the few seconds you're no longer at peak output, but I never did like or get into SPL events. I'm more of a purist for SQ and design innovation as opposed to "I'm louder than you are."
I figure after 150dB, it's no longer fun to be in the car.. not for me anyway. maybe why I still have my hearing haha

hey most people never run the system at full output anyway so even if the alternator is a bit shy, they never actually pull all of its output.
remember, every +10dB, or 2X the volume to your ears, takes 10 times the power..
so even turning an amp down to half the volume can drop from 1Kwatt to 100 watts.
HUGE difference and one most daily drivers and ever parking lot bangers will never experience.

A lot of what we've debated will depend heavily on teh application.
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