American Bass mystery amp

I have an American Bass amp on my work bench that has a couple of shorted output mosfets. IRF3710.

My problem is that someone has gone to great lengths to hide what kind of amp this is and what ICs are used inside the amp.

It looks like the output mosfets are directly driven by a socketed IC. It’s been masked over. I’m wondering if it may be a HIP4080.

There are no markings on the top or end plates to identify the amp, and bottom plate doesn’t have a sticker on it either. I do see a partial serial number.

The board version silk screen has been masked over as well.

I will include pictures.

Any info this community could share would be appreciated.



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OK. get some new parts, but previously check the drivers. Usually they came fom a specialized IC or discrete parts, that will be checked with a DMM using the diode function for short circuits. Usually there are some low value resistors at the gate of the MOSFET's, in the range of 10 to 47Ω. See if any of them also are kaputt. If the answer is yes, see if any other component in the PCB looks bad, you have other channel to compare resistance values and diode drops. All this with the unit unpowered.