A strange problem w/ two amps.

[GoBlue]

Ive got two Alpine amps, a 4 channel, and a mono sub. I just hooked em both up and only the sub is going. I have used the 4 ch. before so I know it works. The 4 ch. is ON, but no sound. Can you destroy an amp by touching the ground and power together or sparking the power cords? I did that once or twice. I have narrowed it down to that, or not setting my head unit up right. Im pretty sure its all fine, I personally think there is an amp problem. Any ideas?

Deck: Pioneer deh-p6800mp

[exalted512]

Youre either:
Not getting signal to the amp
Causes:
Bad RCA
Bad head unit output
Head unit output is turned off
RCAs came undone at amp or radio

Amp not getting enough voltage/current:
Causes:
partially blown fuse
pinched power wire

Not getting signal from the amp:
Causes:
amp outputs are bad
speaker wire cut/pinched
terminals inside the box or at the subwoofer disconnected

Bad sub

To test:
Since you have another amp, unhook the good amp and put the amp in question in its place. If it still doesnt work, thats 98% guaranteed its a bad amp.
-Cody

[GoBlue]

I swapped out amps and found out that it doesnt work with the sub either, so how would a brand new amp go bad, but still turn on? Is it something that I did maybe?

[exalted512]

Is there a fuse on the amp? Try replacing it. If it still doesnt work, its probably the amp.
-Cody

[ShinAce]

Shorting the power wires should not damage the amp. Keep troubleshooting.