Phoenix Gold M100 no regulated voltage

This amp also is not producing +-16v regulated voltage and instead has +-2.5v. Rail voltage is +-40v. The regulated voltage is produced from rail through two pairs of 160ohm 5W parallel resistors. Mid-step I measure +-26v, but on the side which connects to all other components such as opamps, diodes, and the gambit I'm only getting the +-2.5v. Just after the 5w resistors theres a couple unknown diodes possibly 16v zener I guess.


It would appear that this amp may be muting by way of regulated voltage drop down but I am not 100% sure. Theres an optocoupler mid-board next to several diodes near the rail caps. No small transistors, diodes, and other tested components are coming up as concern. The amp was re-capped and aldo BurrBrown converted for the 2 OpAmps near the speaker terminals.

What holds the regulated voltage down in this amp?
 
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Dang.

Infrared heat scanner found one of the BurrBrown opamps heating up to ~140F. The previous tech socket'ed it. I pulled it and regulated voltage is now restored to all components.

BB OPA2132P

One of these is still working.

The rest of the amp has about ~6 or so BA4560 opamps.


I'm going to try putting TL072 in for further testing. I dont have any BurrBrown units.