Want to run 4 amps,subs, speakers- how to wire???

Questions about Car Audio
motorheadmatt
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Want to run 4 amps,subs, speakers- how to wire???

Post by motorheadmatt »

Hey guys had some quick questions:

i want to run 4 amps in my car:

2 X 2 channels (for 4 subs)
2 X 4 channels (for speakers)

but my deck only has 3 RCA's, but i will need 6 i plan on spliting the 4 channel amps

is it bad to split all the rcas???
will i loose power???significantly???
how would you recomend i wire this setup???

cheers, your help is appreciated.
IZU069

Post by IZU069 »

Not that I'm into car audios - except to say get a second battery instead of a capacitor - unless you're in it for the looks as most seem to be; but....

If I understand, you only have a 3 channel head - I presume left, right & sub.
If so, isn't it better to get a 2 channel & a sub? (Or are you phase splitting for pseudo-quad etc).

Splitting the cables depends on signal levels & impedance matching, but I'll leave that for other gurus. Home HiFis have typically 10k input impedences whereas car audios often seem to assume a powered input (like 2-8 Ohm of a few Watts).

And I hope your charging and battery system is up to it!
Last edited by IZU069 on Wed Jun 11, 2008 10:50 pm, edited 2 times in total.
motorheadmatt
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Post by motorheadmatt »

yer got myself a custom made alternator and 2 odysey batteries- i dont want to run capacitors- ill have to wait and see when its working if i will need them or not.

EQUIPTMENT:

4 pionneer champion series subs
2 JBL Monoblock Amplifiers

4 sets of Pioneer 6x9's
2 4 channel Pionner Amplifiers

Pioneer head unit -3 RCAS one extra set of pioneer 6x9's will be running of the head unit
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Post by iSueZoo »

Capacitors are never needed - it's for looks, or to ripoff the unwary.
I am open to proof to the contrary, but a recent SillyChip article repeated my views.
If in doubt, compare the ESR and energy stored in a battery - especially AGM like Odyssey to the biggest cap you can find (synchronous machines excluded).
Besides, the caps should be on the PSU filter side - ie, at about 70VDC or above in the amps! (What's the ESR of a cap AFTER it goes through an SMPS?)
Or show me the clipping pre- & post- capacitor fitting compared pre- & post- cheap nearby battery addition. (And use oxy-free Aluminium cable please - not this copper crap!)

....................
POST-EDIT: After writing the above I spied a 1F cap at JB HiFi for over $400. That's an expensive piece of wank. I can't understand why audiophiles complain about AGM battery prices, nor petrol prices for that matter!

Later I met another "audio" expert (at a dedicated car audio shop). Looking for clues as to why my Alpine display failed, I asked if it was a common fault and what the max operational voltage was. "13.8V". No - not rated voltage - max voltage! "Oh, 14V." Well I suppose Alpine can expect a lot of returns if the standard charging system is set to 14.4V! The clueless reply - "but that's from the alternator - it's not through the battery". (Got home: Correct answer is 16V.) I wonder if he's related to the guy that reckons AGM and gel-cells and all sealed batteries are the same? He's been delivering batteries for over 18 years so he knows!
Sorry - I just really seem to attract them!

Maybe I'll resurrect my twin 1800W (RMS of course!) system for loud campers.
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motorheadmatt
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Post by motorheadmatt »

anyone got any idea how to wire my setup...will i need a deck with more RCA's

ive been told it could lower my sound volume and quality by some if i split the RCAs

and ive been told by some that it will only lower my signal from the deck????

any ideas or help?
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Post by pig75 »

Just use splitters.
We used to run 8 amps off the sub channel in the coronna and never had a problem with the loudness :lol:

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modern bliss
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Post by modern bliss »

use the amp outputs (connecting all the amps in a 'trail') these out puts are Pre-amped so you don't have to worry about loosing power across the splitters.

caps are s*#t, battery still has to charge the capacitor + run the audio while capacitors charging.


And why 4 subs? have you already bout these products?

i would be running everything at 2 ohms (1 ohm if the gear allows) to save buying amps.

I'm in a bit of a rush so i havent really read all your posts.

Pat,
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SICKTG
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Post by SICKTG »

motorheadmatt wrote: 4 sets of Pioneer 6x9's
LOL
motorheadmatt
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Post by motorheadmatt »

SICKTG wrote:
motorheadmatt wrote: 4 sets of Pioneer 6x9's
LOL
actually its 5 sets- one set will run off the head unit

cheers, thanks for da help
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Post by archangel62 »

motorheadmatt wrote:
SICKTG wrote:
motorheadmatt wrote: 4 sets of Pioneer 6x9's
LOL
actually its 5 sets- one set will run off the head unit

cheers, thanks for da help
ROFL
oh man, you're doing it wrong...

No offense but this sounds like the biggest waste of money I've ever heard of. I've seen plenty of Pioneer show cars, especially back in '05-'06, they were the worst sounding s*#t ever and weren't even loud.

For starters, why run two 2ch amps for subs? Get a proper monoblock, run all four subs off it at 1ohm, or if they're dual voice coil subs get two monoblocks and drop each amp to 1ohm.

For seconds, why the hell are you running 6x9s, and again, WHY PIONEER!! If you want fullrange, get splits. If you want bass, get better subs. 6x9s are for budget wannabes who can't afford or don't want subs, no offense anyone (my daily has 6x9s).

Don't run anything off the deck if you can help it. That's a whole 18w RMS if you're lucky and could increase distortion and noise on the RCA outs due to heatsoak and power drop.

Two 4 channel amps could be of benefit, depending on your application, but you might not even need them. What are you trying to do with this car? SPL, SQ? You can get buckets of loud with one decent 4ch amp, and if it's worth what you pay you should be able to run 8 speakers off it anyway (parallel), it's not ideal but why the hell do you need 8 fullrange speakers anyway? You'll only get clashing soundwaves and varying frequency responses of the speakers resulting in audio mud. Just buy quality speakers for each end, and if you absolutely must run several pairs, run their components (yes, components, i.e. splits, not coaxials/6x9s) right next to each other so the percieved soundwave clash is minimal.

Quantity is not a substitute for quality. Pioneer suck rats balls.

Edit: As for the RCAs, if you run less amps it won't be as much of an issue, splitters shouldn't be too noticeable if you only split a couple of times, alternatively you could fork out for a preamp or other unit that actually powers its own RCAs. You can get RCA level boosters I believe which are basically the same thing (then you can just hang splitters off of them). I'd advise using two RCAs for fullrange and splitting one for subs, to preserve stereo where it counts. For all that money though, you may as well get another deck that has 4 outs, so your subs can be stereo too. It sucks when bass testing songs are in stereo and you only get one channel, trust me. But of course, if you're running subs in stereo, make sure the lefts and the rights are in a separate box/boxes, or inverse soundwaves can cause a massive jump in excursion, i.e. the subs will top out and kill themselves.

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modern bliss
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Post by modern bliss »

lol mate your working on the pile of s*#t theory...


you have a pile of s*#t you add to it... still a pile of s*#t.

more does not = better.

Your going to spend all this dosh on gear, that you don't need, thats going to sound shittier then my daily running one sub and splits.


+1 no for 6x9's, why do you need the lower frequency band that 6x9's offer over 6inch when you have 4 subs lol.... and no you don't need 4 subs.

Pat,


List for us what you have, and how much more you are willing to spend and we will all give you a good idea of a) what to buy b) what to swap/sell. Can't hurt can it, save money, sounds better....can't lose.


Pat,
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modern bliss
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Post by modern bliss »

archangel62 wrote:make sure the lefts and the rights are in a separate box/boxes, or inverse soundwaves can cause a massive jump in excursion, i.e. the subs will top out and kill themselves.
My mate use to run 2 subs in the same box, one was dead, use to fool all the ricers when they both moved. same displacement, opposite direction, did look odd with a large note, one go in would one go out... haha. Had a cool kind of ported sound to it.

Pat,
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Post by SICKTG »

modern bliss wrote:
archangel62 wrote:make sure the lefts and the rights are in a separate box/boxes, or inverse soundwaves can cause a massive jump in excursion, i.e. the subs will top out and kill themselves.
My mate use to run 2 subs in the same box, one was dead, use to fool all the ricers when they both moved. same displacement, opposite direction, did look odd with a large note, one go in would one go out... haha. Had a cool kind of ported sound to it.

Pat,
altough i have heard a bit about subs killing each other im yet to see it i know a few people that have had 2 subs runnin in a non sperated box and no dramas years after
modern bliss
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Post by modern bliss »

SICKTG wrote:
modern bliss wrote:
archangel62 wrote:make sure the lefts and the rights are in a separate box/boxes, or inverse soundwaves can cause a massive jump in excursion, i.e. the subs will top out and kill themselves.
My mate use to run 2 subs in the same box, one was dead, use to fool all the ricers when they both moved. same displacement, opposite direction, did look odd with a large note, one go in would one go out... haha. Had a cool kind of ported sound to it.

Pat,
altough i have heard a bit about subs killing each other im yet to see it i know a few people that have had 2 subs runnin in a non sperated box andno dramas years after
Not sure who your responding to there, if your talking about mine, one of them was dead.

If your talking about Arch's he was talking specifically if they are wired in stereo (correct me if i'm wrong)....

-Although now i think about it, if they are the same sub they will have the same volume difference (+ and -) max as each other.

If right channel sends signal to move +30mm and the left one -30mm the volume of the box remains constant (putting heat change aside) pressure would be constant, ie dv=0, dp=0. this is at the most extreme (other then both same direction, but thats not a stereo specific issue) point, its effectively acting as a (single sub - dv), in fact making it better for the sub. as less pressure it being placed apon it.

I'm open for correction on this as I'm sure I've made a wrong assumption , because I've heard not to put them in the same box as well. Interesting none the less.

Pat,

**i realise now that +30 and -30 don't necessarily mean same volume, depends on cone shape**
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archangel62
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Post by archangel62 »

Yeah, but the difference is there's less compression on the sub (sealed box vs. ported box) so it ends up being like running the sub free air, or worse. In most cases it'll be fine, but in the rare circumstance of a full gain, low frequency note that's roughly 180 degrees out from left to right, it can do some physical damage to the sub. Usually fine though, and alot of times subs in the same box are recieving the same signal due to RCA splitting or the wiring.

And I totally agree with pat's comment "you have a pile of s*#t you add to it... still a pile of s*#t." :lol: exactly right
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