Pulsing idle, voltage drop. Bad alt? W/ video

[1986nate]

Get one of the high output alternators, this should solve the problem

[SoCal LS-L]

And a quality capacitor would help as well, it stores energy when your amp isnt drawing as much power between beats, and releases it when your amp needs the power to push the speaker. This helps your amp push your speakers harder and also decreases the strain on your charging system.

[Trevor]

The fault within the amp. will not have been caused by a lack of voltage/current. The only B+ supply problem likely to cause an internal fault, would be an over voltage, due to a faulty alternator voltage regulator, and this would need to be more than a short spike.

As the protective circuit is operating, excessive current drain is indicated. This in turn indicates a fault within the output stages, usually related to speaker issues, causing one or more output power transistors to become overloaded. Hopefully this will be the situation, meaning that the amp can be repaired.