Subs causing car to lose power

[Denno]

When I'm driving along, and my music is going pretty loud, subs are going too, my car seems to lose power. Like whenever the bassline hits, it takes power away from the car. It isn't a problem, but it's noticeable and I just want to make sure it isn't going to become a problem. When I turn my music down, it doesn't happen at all, so it's definitely caused by the subs.

I have an 2 Pioneer 12 inch 400W RMS subs with an Alpine MRP1000 giving my subs 1000W RMS.
I have a stock alternator, battery and wire running between alternator and battery (stock as far as I know anyway).
My amp is powered using a 4gauge wire, and the ground wire is also 4 gauge, running straight back to the negative of the battery.

If you need any more clarification then please let me know.

Cheers

[IMCRZY]

I have a Sony 1000WRMS amp and 2 sony 1400watt 15's running with 0g cable and stock alternator but bigger battery and mine is fine unless its running full tilt

when you start you car hold down the up and menu buttons so its showing volts and then turn it up it will show you hown much voltage drop you have on the bass hits...

the only way to fix this is to put in something like this BN AUDIOBAHN ACAP7P 1 FARAD DIGITAL CAPACITOR CAR CAP - eBay Amplifiers, Audio, Video, Car Parts, Accessories, Cars, Bikes, Boats. (end time 09-Jul-08 19:53:12 AEST) and or upgrade you alternator and battery

But your system is fairly average so you shouldnt have a problem

[Denno]

lol fairly average, doesn't sound fairly average mate, and it certainly makes my car lose power, so I do have a problem. Thanks for the info about checking that voltage thing, I had no idea you could do that. That's still the same for the single window trip computer? Thats what I have so just making sure I can still do it on that..

[IMCRZY]

Yea it just shows up a diagnostic display there is a thread about it on here somewhere...

And the only prob u will really have is your lights dimming

Have you had a db test done on it? what does it pull?

[VH commodore]

well when your sub beats the amp draws alot of power so the alternator has to work harder therefore making it harder for the engine to turn it requiring more power therefore less power making your car move forward... lol kinda drunk and easiest way i could say it lol.

[VH commodore]

a good battery will lessen this affect.

[Denno]

IMCRZY - I definitely know about the lights dimming, quite annoying to have to turn the bass down at night lol. I haven't had a test done on it, not really interested, it freakin loud, and I can hear it very clearly from about 100metres away so I'm pretty happy haha (I actually tested that today, I ran down the street and got my sister to turn it up lol). How would I go about testing it to get a number?
VH Commodore - thanks for that clarification, that actual makes perfect sense. To fix it would I need a bigger alternator? Or would that not fix the problem? Capacitor then?

[VH commodore]

capacitor would fix the lights dimming, not sure bout better alternator, my first choice would be a high quality battery, that should fix everything.

[IMCRZY]

Local audio shop should be able to help you out...

And the draw would be hardly noticeable to performance

With a db tester i have pulled a max of 143.1dbs car not running

It will put the volts down under 10

And if its that loud you shouldnt have it up while driving

My eyes go blurry when mines all the way up not so safe i would think

[Denno]

ok thanks VH commodore. Any suggestions as to what I should get? I have heard about OPTIMA batteries, but is that a bit of overkill for me? Also, they're kinda expensive ay.. So hopefully something not too expensive, but still good.

Thanks

[VH commodore]

dont know im not a battery expert but at work we use 'turbo battery's' they seem good. anything thats expensive is good lol.

[Denno]

lol ok mate, i'll look at some expensive stuff then I guess. Thanks for the help

[bezz]

Try turning down the gain a little on the amp. Sounds like the signal is clipping which in turn is causing the amp to draw too much current. The bass probably sounds muddy when that happens too. The stock vt alternator should be able to cope with your setup.

Failing that try the expensive stuff

Also don't bother with a stiffening capacitor, it wont do anything.

[Denno]

Thanks bezz. I was pretty sure te capacitor wouldn't do anything, I hae been reading another thread about headlights dimming, so I wasn't really goingto bother with that :P. The bass doesn't sound too bad? Although I don't actually know if I have set the gains properly or not to be honest. I was going to get my mate to have a play with it when I saw him next, and I have seen him for a couple of weeks lol. I'll see what I can do with the gains, but I don't want to loose the amount of overall bass...I freakin love the stuff lol.

[bezz]

Gain settings tut
this should help, links over to mea

Basically, clipping = bad, puts strain on the voice coils of your sub which can kill them over time. Not too good for your amp either.

[Denno]

Wow you're up late man haha. Yeah I know clipping it bad, but I was reading my amps book, turn it up until you hear distortion etc. But I didn't think I could hear distortion? This is why I wanted my mate to have a listen, bcuz he used to work in a car audio shop, and he would know what to listen for. Thanks for the suggestion, I'll have a look at that thread over there and see if I can gt my head around it.
I don't wnana change the direction of this thread too much, but with my headlights dimming, would that be related aswell? Or is that a case of battery and/or wires, bcuz you said my alternator should be fine.

[bezz]

Exam study (procrastination) man, gonna be up for a few hours yet lol. Yea distortion is a lot harder to hear in subbass frequencies, you just have to listen closely to hear if anything sounds 'fuzzy' when you crank the volume up. I reckon it might have something to do with your headlights dimming too. I run 2 amps in my vt using the same alternator you have and don't have any dimming or power loss whatsoever. I'm also using a regular battery with no upgraded grounds or anything.

edit: woo 500 posts

[Denno]

haha nice work on the 500 bezz. what exams you studying for? Uni or high school? I got a uni exam tomorrow morning haha, should prob get some rest but I think I'm gonna do ok, so I'll stay up haha.

Ok I have been reading that thread you linked me to, and I think I understand now. My alpine deck claims to have 4V pre-outs, so judging by the thread, I need to set my amp to around 1.3V? (this is exactly what the thread said lol).
If this is the case then I will be setting the gain properly before I head off to the exam tomorrow , I'll let you know how it affects everything.
Oh also, my amp has things like Bass EQ and LP Filter. I know the LP filter is just the setting for below which frequencies my sup should be playing, but the Bass EQ? Will this have an affect too? (It goes from [full anti-clockwise] 0dB to [full clockwise] +12dB.

[bezz]

got 1 exam left on friday, engineering project management.. pretty straightforward topic and the exam's open book so I'm not too stressed.

Yea set the gain to around that level and see how it goes. After that you should play around with it a bit to try and achieve a 'balance' between the sub and your speakers (that tut explains it a lot better).

The lowpass filter just sets a cut off frequency for the amp, so around 85Hz should be fine (dont be too concerned about it being exact as filters roll off slowly, they dont cut at the exact point). Bass EQ is a bass boost function, an equalizer specifically for the subbass. Generally leave it low until you've set your gains properly, then you can muck around with it for fine tuning.

Good luck with your exam tomorrow man, what course you do? Spose I should get back into the study now...

[Denno]

Ah nice, which uni you at? Which year etc?

I'll definitely play with it quickly tomorrow morning then, wake a few neighbours up haha.

I'm doing Software Engineering at flinders, in my second year. Cheers for the luck mate, good luck to u too, although as you said, open book, should get a HD! lol

[bezz]

Ha no ****, I'm doing computer/electronic engineering at flinders, Adelaide's a small place hey. I'm in 4th year technically but i did 2nd year part time over 2 years so I'm halfway through 3rd year now. Trying to organise work exp for next semester atm.

[Denno]

Oh really? Well I started out in Computer/Electronic engineering in first year, did not like the electronics side at all, and changed to software in 2nd year (I love the electronics side now that I have actually found a real world use for it - in my car!!! haha). I f****d up 2nd year, failled too much, so I'm technically in my third year now, but just repeating the subjects I stuffed up last year lol. And yes, adelaide is a very very small place ha. I'd be doing just as you are now if I didn't stuff up last year, but work experience will have to wait til next year now...

Well I'm going to head to bed now mate, getting a little bit of rest before an exam is probably the right thing to do lol. I'll prob bump into you round the traps, and not know it haha. Good luck with the work experience.

[garfa]

I'm back!
Miss me Bezz???

Ok, too much stuff to read, so I can say that the problem is bad wiring.
1000Wrms is not much....... and as such should bnot effect the car at all (I know a stock vs with **** battery and alternator that has never been tested) has no problems with about 1600Wrms. No headlight dimming or anything.

Re wire the whole install.
Add the 3 magic grounds: engine to chassis/batt to chassis/batt to engine. use cable equal to/or bigger than pos sized cable.
Run ground from amp to the chassis. use a multimeter to find the best spot. I have had good results with the floor.
if all the above does not fix then run multiple grounds from the batt to the chassis floor.

[VrWagz1]

Your lights are a good indicator your wiring is not up to scratch on your amp
1. Amp cable to small
2. You havnt earthed it properly under a good bolt (with no paint)
3. You havnt upgraded you Batt- to chasis wire.
You can read a bit about it in this thread Dimming Lights

[Denno]

ok thanks garfa, I was about to come back on and say that playing with the gains did nothing lol. I had it set to jus under 1.5V (which I thought meant it wasn't amplifying the bass that much, so I changed it to be roughly 2 I think, not exactly sure as there is only a marking for 0.5V and thats it. Also, my Bass EQ level is turned all the wy to the left, and always was, so that wasn't a problem.
I was scared that it might be wiring, bcuz I have spent $170 on wires for it already...the guy at jaycar said I that because I have so much power running through my system, I should run the ground straight back to the negative, I was walking out thinking to myself, did I just get screwed over, and I have since come to realise.. Yes I did get screwed over . (theres a reply for VrWagz1, I have a perfect ground - the actual negative of the battery lol, which also means the wire going from my negative to chassis wouldn't be a factor either).
Also, I have used 4ga wire, as I asked in here, and I believe it was bezz who said it would be fine for what I was going to be running??
The book for theheaduit says I should run a 2ga wire from the battery to a distribution block, with a 4ga wire - no longer than 1m - to the power of the amp. The only reason I haven't done this is bcuz bezz said I should be fine..(Car Audio Wiring)
So to clairfy, I have 4ga running from positive on battery to power in amp, and 4ga running from ground on amp to negative of battery.