Hifonics Zeus vIII Power supply issues

I have this amp in for repair that the power supply MOSFETS were shorted.
Removed dead MOSFETS, checked for drive. Had good drive. Replaced all the MOSFETS and checked for proper drive, and don't get proper drive.
Attaching picture to show current drive.

Also this amp has modifications done from a previous repair. Has anyone seen this before? The TIP transistors are attached to the TIP35 regulator transistors.
 

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zeus VII

There are no TIP35/6 regulators in this amplifier.

The circuit of the power supply is somewhat complex owing to the three stage supply I designed.

Without a complete knowledge of how these PWM systems work it will be tough to repair the amplifier.

It requires several modifications which we do on repairing/restoring these (and we do a lot of them) to make the supply more reliable and reduce the turn on surge current to almost zero.

Steve Mantz
Zed Audio