How to identify damage to internal parts

[joshpoints 10+ year member]

I opened up my amp because it stopped working. I was playing it loud one night and my lights were dimming excessively and then it cut out and came back on so I turned that amp off. later that night i checked to see if it would make any sound and it wouldn't and didn't work the next day. I believe it was due to lack of juice going to it. But now that I have the amp opened I see no signs of damage. I don't smell any burnt electrical smell, no melted parts or burn marks. Everything looks like new. The power light comes on and the protect light is off when I hook it up. Where should I look for damage when an amp is starved of amperage. Thanks.

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[Ruffy 10+ year member]

Bulging Capacitors.

Scorch marks can be on the bottom of the circuit board as well. Might wanna take the board out and look at it thoroughly.

My understanding is an amp thats starved for amperage ends up frying itself with voltage? Or wasen't it the other way around. Not enough volts and it keeps drawing more and more amps. If it's coming on and the protect light isn't on, and you dont see any obvious damage, then it seems to be ok.

 

[joshpoints 10+ year member]

Bulging Capacitors.
Scorch marks can be on the bottom of the circuit board as well. Might wanna take the board out and look at it thoroughly.

My understanding is an amp thats starved for amperage ends up frying itself with voltage? Or wasen't it the other way around. Not enough volts and it keeps drawing more and more amps. If it's coming on and the protect light isn't on, and you dont see any obvious damage, then it seems to be ok.

I'll take out the circuit board look at the bottom and if I don't see any issues there try it again in my car. Capacitors look fine.

Edit

Can't see the other side of the circuit board. The inputs and things that attach to the circuit board would have to be removed. I'm still going to try and get it to work in my car. One test I'll do is run the preamp inputs into it and then use the line output to run my other amp and see if my other amp get a signal to put out sound.

 

[azngotskills 10+ year member]

have you tried checking all voltage readings and connections in your set up (power, ground, RCAs, speaker)?

 

[joshpoints 10+ year member]

have you tried checking all voltage readings and connections in your set up (power, ground, RCAs, speaker)?

I know the power wire is sending 12 volts. The remote wire is sending enough to turn on the amp. I haven't checked on the ground, but I believe I set it up so both amps ground to the same location. I'll check the ground though. The rca's that run to the sub amp were hooked up to my mids and highs amp and it sent a signal for sound.

 

[project f-150 10+ year member]

i think its if your low on voltage the amp draws more amperage. unless its an unregulated power supply.

 

[joshpoints 10+ year member]

i think its if your low on voltage the amp draws more amperage. unless its an unregulated power supply.

The strange thing I just thought of today is my 60 amp inline fuse running to the amp should have blown if I was anywhere near its RMS rating of 850watts correct? And if like you say the voltage dropped causing a greater amperage draw then the fuse should have blown. I hooked the amp up and I couldn't get it to work today. Placed another amp in car with same wires and it worked. When I hook up the damaged amp power light still comes on the protect light is still off and I can hear the internal fan running. The only thing I can think of is somehow a lack of wattage going to the amplifier causing it to strain to produce enough juice on the below 60 amps and below 12 volts causing excessive heat and in turn causing damage without blowing the 60 amp fuse?