Recently installed a Pioneer GM7300 amp into a 2008 Mitsubishi Lancer and have had lots of problems. All wires are fine, amp has power and a good ground - running high-level inputs from the rear speakers. The amp was running a single 12", now running two 12"s and has the same issues. No music coming from the subs, but a 'pulse' every few seconds, regardless of whether the amp has an input. The amp worked fine when it was installed, came back a few days later in this state. Sent the amp away for warranty, installed same model amp and it was all fine. Three days later, the car comes back in with the same issues.
Any idea's what the problem might be? All I can guess is the factory headunit has too high of a signal running to the high-level inputs, and it's frying something in the amp.

What sort of 12's are you running and also what impedance is the amp seeing? have had a few probs with these amps.

The single sub was just a blue-coned 4 ohm Pioneer, the duals were the same sub run in parallel for 2 ohms.
Not completely sure on model, but it wasn't anything out of the ordinary.

Try installing a Line Out Converter and see how it goes.



Can you elaborate on this, what input do you mean?

Customer is waiting for a Rockford Fosgate 3Sixty.1 to come in, just trying to solve the problem before it's fitted.
Sorry for ambiguity, regardless of whether or not the high-level input is plugged in or not. I'm thinking there could be some sort of ground-loop happening, but I'm not sure how.

So there was never a problem running the single sub at 4 ohm?
But since it's been running 2 ohm two amps have died?
Did you see the amp die the second time?
Where are the gains set?

I have a feeling they might just be overdriving the amp... Running it too hard until it cooks or maybe theres some resistance on the power or ground wiring causing some voltage drop on the supply which can also kill it.

I've run them clipping on a dummy load for extended periods and occasionally the output transistors die if the clipping is too severe, but this is after the amplifier heats up so much you can't touch it.

It's died on both a single and dual subs. I have no doubts that the system has been turned up way too high (although it's a new car, the rear speaker surrounds were starting to look not so healthy), so I'm sort of leaning towards overdriving the inputs at the moment.

We didn't see the amp die both times, gains are around 7-8.