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Amp Shutting off + more

Posted: Wed Aug 31, 2005 5:40 pm
by r3ap3r911
Hello all!
Need a bit of help with my setup, I have a Kenwood KAC-9152D Mono block amp pushing 2xKicker CompVR's dual 2ohms... I've got 2 gauge wire from the amp to battery, and a ground wire close to the amp.... I have also just put in a new capacitor (which i think was a mistake), that is also tied into this, the way i have the cap hooked up is (+Battery TO +cap TO +amp, and i have ground from -amp, to -cap, to chassis)...
AND My question is this.... My amp shuts off when i hit a certain volume.. Sometimes very different from another.. I just replaced my alternator thinking that the whining noise it was making meant it was dying, but no... The new one whines aswell.... I'm wondering if the cap also has to be grounded or? ANY help would be greatly appreciated... I have a 3-4 months old/new battery in the car so i didnt think that would be the culpret, so only thing i think is ground from cap.. Also... Car has been stalling from time to time on a daily basis, i look at the battery gauge on my dash and battery goes up n down (without the deck even playing, just ON) AND the RPM's on the car with also fluctuate WITH the battery, and alternator(so it sounds), the alternator will also contribute and make that whining noise AS I rev the car... ANY HELP is good help, so plz throw around some ideas :) :sm29:

Posted: Wed Aug 31, 2005 5:43 pm
by r3ap3r911
THE amp will shut off for a period of 1 second to 5 seconds.... THen turn right back on and start playing again... But if i havent turned the volume down by the time it turns back on it'll go right back off again...!

Posted: Wed Aug 31, 2005 5:46 pm
by r3ap3r911
Also!... The car will only act up at certain times in the day, no matter how to tell when its going to act up.. But when it does, all it wants to do is turn off likes it not getting enough power.... I push in the brakes, Boom, it stalls... I try to use heater, boom stalls.. Just put in a new 105 Amp Hitachi alternator, the battery is a motomsater 72?... and the CAP is a Stinger cheapy 1 farad.. think 16v/24v or something?.. anyway.. thoght that idea might help..

Posted: Wed Aug 31, 2005 5:48 pm
by r3ap3r911
Oh yea!. I have the subs running in Parallel... And im not TOTALLY sure, but i was running dual 4 ohm subs in parallel the other day and i was reading 1 OHM?! on my meter... So i got these hooked up the same way and they are also reading 1ohm?!.. anyway.. i want 1 ohm cuz the amp supports it, not FULLY, but its stable... maybe that could be a reason also... but i highly doubt it.

Posted: Wed Aug 31, 2005 6:19 pm
by smoker
what just happened? did you figure it out yourself or did i miss something? im pretty sure kenwood does not make a 1ohm stable amp though it doesnt really explain everything going on.

Posted: Wed Aug 31, 2005 6:20 pm
by r3ap3r911
No Its not resolved.. Im not sure how that got on the title of my post... Im just adding comments as i think of them... YES the Kenwood amp KAC-9152D is 1ohm stable, 900 watt RMS

Posted: Thu Sep 01, 2005 4:17 am
by Ryan from Ohio
You need to ground the amp seperate.

Didnt I already answer this queston on here or CAF?

Your car itself has car issues. Disconnect the stereo system and have a shop do a diagnostic on it. Make the necessary repairs. The Audio system is not causing your car to stall.

So ground the amp independantly. Get the car fixed, then update us.

Posted: Thu Sep 01, 2005 8:48 am
by GlassWolf
If the amplifier is shutting off like that, it's going into thermal protection mode. that's caused by one of the following reasons:
-weak charging system, not enough current for the amp causing the amp to clip.
-amplifier power wire too small, causing lack of current (bad ground can do this too_
-gain set too high on amp, causing amp to clip
-too low of an impedance presented by the speakers.


if the whining you hear is through the speakers, that's a bad ground point somewhere. usually at the head unit. or, it's caused again by the amp gain set too high and causing a feedback through the speakers.

as for the car stalling out, go to auto zone or advance auto or pep boys and get your alternator and battery both checked under load by someone there. it's free, and they can tell you what's wrong. you have an electrical issue with the car though and you need to get that fixed. That's potentially hazardous to you and others on the road around you.

ok..

Posted: Thu Sep 01, 2005 11:47 am
by r3ap3r911
So i've unhooked the ground that was from the amp, to cap, to chassis. and put it to the same chassis ground, just on its own wire.. the cap has its own wire aswell, im using all 4 gauge... Did that this morning before work and I can say that it deffinately helped out alot! I can play out loud music beyond what i usually before the thing turned off.... So this morning im cruising to work, pumped it up a bit to show off to my co-worker, and Boom went both AMP fuses, both 30 amps were fried... After pondering, and looking around for the ground cable to be loose, i find Nothing.... Popped a couple 30's back in and she runs fine now...? not quite sure...
I'm also just about to replace my deck ground cable.. Tell ya how that goes when im done..
Thanks for all your good input thoughs who replied :) Appreciated!

Posted: Thu Sep 01, 2005 11:50 am
by r3ap3r911
r3ap3r911 wrote:So i've unhooked the ground that was from the amp, to cap, to chassis. and put it to the same chassis ground, just on its own wire.. the cap has its own wire aswell, im using all 4 gauge... Did that this morning before work and I can say that it deffinately helped out alot! I can play out loud music beyond what i usually before the thing turned off.... So this morning im cruising to work, pumped it up a bit to show off to my co-worker, and Boom went both AMP fuses, both 30 amps were fried... After pondering, and looking around for the ground cable to be loose, i find Nothing.... Popped a couple 30's back in and she runs fine now...? not quite sure...
I'm also just about to replace my deck ground cable.. Tell ya how that goes when im done..
Thanks for all your good input thoughs who replied :) Appreciated!

I'm just assuming that the amp 'gain' is set too high.. but why? and how?.. the subs should be able to handle 400 rms each and ive got 900 rms total, but only set to about half?... unless im otherwise reading the amp gain wrong, and the .5 , .4 , .3 means only a certain amount of watts/power compaired to the actual number 1 2 3 4 etc before the first half of the dial gain... I duno!