amplifier keeps dying

[sedain]

infinity kappa perfect 6.1's (x4) *components...........4 ohm?
the amplifier that powers the speakers is a 400 watt rockford fosgate, 4 channel amp... 4 ohm

the other amp is a 500w rockford fosgate that is for teh subwoofer...
10 inch rockford fosgate p3 400w sub

the shop that has been doing all the warranty work says these are matched etc and there shouldnt be any issues...(the speakers peak power is 400w??is that per speaker or for each set of the components???)

last time i took it in i had them install a capacitor despite them saying i shouldnt need it and my headlights no longer dim+ this amplifier is fairing alot better than the last two,it takes longer for the amplifier to cut out and i can play it louder... (lol,im glad the warranty is for 5 yrs)

ive had this problem since i had the system installed,when playing at loud volumes the speakers will cut out (amplifier turns off,i believe it has built in protection or something) and at this point i can just turn volume down to half or below and speakers/amp are on again..

*until at which point the amplifier dies (im on my 3rd amplifier in 3 months and i will be going in for another replacement soon if i or they dont find the problem...

(subwoofer and the amplifier powering the subwoofer do not cut out during this, it keeps playing and i havent had to replace the amplifier that is hooked up to sub even once)

i have a few ideas:::
maybe the speakers are wanting more power than the amplifier can put out???
maybe the alternator isnt supplying enough power and the amplifier is the victim of this??? is it possible for the alternator to be still working but not working well enough?

i dont believe im abusing the system, there is zero distortion in speakers(never has been,speakers could prolly go twice as loud as they currently do)...from what i have read in reviews you should be able to hear this system from a block or two away and ive never been able to turn it anywhere near this loud imo(they have the volume level set low on amplifier i think,ive not messed with it)...in all reality i dont think the speakers are even broken in yet because i dont use the car that much.

the system isnt over 1k watts...it isnt that loud and i should be able to turn it up as loud as i do (i can still hear myself talk when near max volume,for how much i paid i should be able to give myself a headache/earache on demand)...i need a fix.

[sedain]

Re: amplifier keeps dying

more info...recently had to replace battery...the new capacitor has a digital readout of volts,it says 14.0 or around that usually *with car on... so i would think that is good news as far as alternator but i have no clue.

[96firebird311]

Re: amplifier keeps dying

more info...recently had to replace battery...the new capacitor has a digital readout of volts,it says 14.0 or around that usually *with car on... so i would think that is good news as far as alternator but i have no clue.

Pretty much. That shows that the alternator is outputting a charge.

If your sub amp continues to play when your other speakers cut out, and this only happens at high volumes, it sounds like the amp is going into thermal protection. It's simply over heating. Park the car in the driveway and crank it. Watch the amp. When the speakers cut out, do any protection lights turn on? (Or sometimes power light just turns off) Then after the amp has a chance to cool for a minute, the protection light will kick off and should play fine after that. Just for fun, run an extension cord out to your car and put a huge box fan blowing right on the amp. Crank it again. Bet it never cuts out.

The funny thing is, you have a shop looking at this over and over again. I would think they'd be smart enough to see what's happening here....

[sedain]

Re: amplifier keeps dying

what you are saying sounds about right,im out of state currently so cant test that atm but i have touched the amp b4 and i can attest to the fact that it is EXTREMELY hot (i got a burn lol).

this T400-4 amplifier was a little under 500$ which was a bit pricey and it seems from googling and looking it just uses a heatsink to cool itself,no fan or anything...

..any suggestions?what should i upgrade to?

i was looking at the rockford fosgate T800 (900$)

in the description it says its great for component speakers which would sell me except for the fact that in the specifications it shows that its rated for 50w x4 @ 4 ohms which is LESS than what the current amp does and this amp is rated at 800 watts wheras current one is rated at 400 watts...(60wx4@4 ohms)

it would seem as though a amp with a higher rating would power the speakers with more ease so less heat is created? the T800 is fan cooled also so it would SEEM like it would solve my problem..

would it not be as loud or would it create any other problems? i wouldnt want a pricier amp that isnt "as loud".

[sedain]

Re: amplifier keeps dying

Park the car in the driveway and crank it.

when not rolling the voltage indicator bounces and goes down to near/at red line at loud volumes. at highway cruising speeds this problem doesnt pop up altho i have seen the voltage indicator bounce a little even at highway speeds..

i was checking into getting an "upgraded" alternator but auto zone and another car place told me that there are no upgraded versions of our alternator although the v8 engine version of our car had a couple of choices to upgrade to.

[sedain]

Re: amplifier keeps dying

The funny thing is, you have a shop looking at this over and over again. I would think they'd be smart enough to see what's happening here....

i dont think they would care if they replaced the amp 10x from what ive seen so far they arent even concerned about it.

an amplifier dying 3x at the price that the thing sells at, you would think theyd be concerned.(i didnt have to pay anything of course,its all been covered under the warranty).

[96firebird311]

Re: amplifier keeps dying

when not rolling the voltage indicator bounces and goes down to near/at red line at loud volumes. at highway cruising speeds this problem doesnt pop up

This is normal. At idle, the alternator is not capable of outputting as much power as when the engine is revved. I believe there was an upgrade available for the F-bodies. Police package? Anyway, I think it was just a 145amp alternator. Nothing huge. Search around this board and the internet in general. You'll be able to pick up a nice one for a few hundred. Say maybe 180amp for $300? Just a guess. And make sure it's high output AT IDLE. This is KEY for car audio purposes.

Regarding the specs on the two Rockford amps, that is a little odd. But I think the T800 is more expensive because it is 1 ohm stable. 200Wx4@1ohm = 800watts. Hence T800. I doubt you'll notice the difference in output between the two amps. Although, you're probably correct in that it will not overheat. (due to the fan AND it running @4 ohms when its capable of 1 ohm loads)

If the amp is too hot to even touch, then its obviously overheating.....:rolleyes: Where do you have your amps currently mounted? Make sure there is air flow across the top of them. If they are currently getting air flow, tell the installers to install a couple computer fans or something blowing right across the amp. Also, do what you can to lower the gain on the amp. Still using the factory headunit? Switch it out for an aftermarket with ATLEAST 4V RCAs. This will allow you to turn the gain down on the amp, but still get the same output.

[sedain]

Re: amplifier keeps dying

Where do you have your amps currently mounted?

trunk on the flat area behind rear seats,its an open space,nothing near them etc.

Switch it out for an aftermarket with ATLEAST 4V RCAs. This will allow you to turn the gain down on the amp, but still get the same output.

when i had the system installed i had them put in a kenwood excelon 891 and that has a 5v out


do you have any suggestions as far as a replacement amplifier/upgrade?

[96firebird311]

Re: amplifier keeps dying

I'm big on keep all amps the same brand..... just a pet peeve of mine. So see what other 4-channel Rockford amps they carry, or consider switching out the sub amp to another brand too. Like I said..... just a preference of mine.

[sedain]

Re: amplifier keeps dying

well, there was paint around the ground for the amplifier that was dying so i think that will prly solve THAT issue but oddly i still find that the system cuts out...

just not the speakers only, now the whole system cuts out including subwoofer lol...

i had the car in for body work and they said theyd look at it and they told me some wires were loose as well as paint being around the ground for the 1 amp (the other ground was fine)..they basically said the installers must be incompetent and there is prly something else wrong with the installation.

they didnt charge me anything extra luckly.

edit: i didnt have alot of time to test it but neither amp seems to get hot at high volume...when i had the car idling i turned volume up to almost max and i was watching amps and system didnt cut out so i rly didnt learn anything...ill do it again for longer when i can find a good place/time when i wont be bothering anyone.

[94Frankenstein]

Re: amplifier keeps dying

Both amps should use the same ground, that is a rookie error on the shop. Basically if the grounds are fairly close they can "overlap" each other and cause noise. Before reading your last post I was going to say bad grounds, I would have the shop reground both amps at a single location. That would be where I would start at my shop. Bad grounds are usually the biggest cause to system problems.

[sedain]

Re: amplifier keeps dying

the speaker amp ground is on driver side and the sub amp ground is on passenger side.

and then there are two wires that run to battery positive terminal,dunno if thats just for power or another ground..it would seem if it was for power it would run to neg and pos terminals.

[dittylopez]

Re: amplifier keeps dying

How bout adding a car audio battery in line?

[94Frankenstein]

Re: amplifier keeps dying

running that little of equipment would not nessesitate an additional battery (it would just put additional strain on his alt), and a cap would not fix the problem. The line going to the battery is indeed a 12v constant, the reason you don't want to got to the battery for the ground, is because the chasis is ample ground (that is where your battery is grounded) and anything longer than an 18 inch ground will most likely result in noise. You need to have both amps ground at the same location in the car and make sure it is a good ground and I am pretty sure you problems will be gone.

[dittylopez]

Re: amplifier keeps dying

I understand about the ground it would not be wise to put a battery in line with the ground, that's just looking for trouble. Also, Sedain, is your amp bridged?