I'm working on an amp for a friend, and I'm a bit stumped. I'm really not all that knowledgeable on solid state circuits. The reverb is dead, both the in and out. I suspect the headphone out, which shares the same power supply is too. Both are powered by 5532 op amps, powered by +15v on pin 8 and -15v on pin 4. At least in theory. The power to pin 4 is only about -2v. Same goes for the headphone out chip. I've already checked the power supply, and it seems fine. If I disconnect the chips, the voltage rises up to -15. Pull the Zener and it will hit -40. I've tried bypassing all RC filter resistors, trying another rectifier diode, removing the Zener. If I remove power to one chip (either the headphones or the reverb) from the circuit, it will rise up to about -3.5v, but still no sound either out from the send or in from the return. Both chips seem to be shorting down the negative side significantly but not the positive. Swapping the chips entirely is very much not easy to do because they are soldered to a PCB that would take a lot of work to remove. Pins 3 and 5 are indeed grounded as expected. Pins 2 and 6 (the + on the op amp circuit) are sitting at about -.025v. I have no idea if that is reasonable. I'm just trying to find a non-power supply related failure that would take down both circuits and drawing a blank. Any ideas? Something could have caused both chips to fail short? Apparently the reverb circuit has never worked since he owned it. Also, is there something as easy to understand and comprehensive as ValveWizard for solid state circuitry? I really need to get this down better. I found the schematic here: https://schematicheaven.net/boogieamps/boogie_nomad45.pdf The reverb circuit is in the bottom of page 4 (in the PDF) and the power supply is the bottom right of the last page.