Well after my dumb mistake a few threads down with the caps I ordered some new ones from Joe and installed them correctly this time. Bring-up went great and was actually pretty fun (once I figured out a good method for setting in the output transistors lol). Once I finished the last bias check I turned the amp on it's side and plugged in my PL4000SI and my phone and listened to music for 30-40 minutes. It was glorious.
After a couple of days I moved it to it's permanent home and finally got to hook my record player up. Halfway through the second song, the system made a loud pop and the meters dropped. I didn't smell anything and I've since pulled the cover off and inspected everything. I don't see anything burned or fried looking but I did check the pico fuses on each board and the right channel ones are toast. I hooked the amp back up to the DBM+Variac and took some measurements at 60V with 10K ohm resistors on the ground/output test points. B+ at 40.70 and B- at -40.82 but the left output had 38.53v and the right had 0.24v. 12R/11R are also at 0.58v and 0.24v.
I'm not really sure where to go from here. I was thinking of pulling the output transistors and inspecting the back of the boards to see if something shorted there. I made sure none of my solder points were long and that I didn't over-torque the output transistors and checked for chassis shorts between each row but, maybe something got in there somehow, I dunno.
Sorry for the long thread, any help would be most appreciated.
After a couple of days I moved it to it's permanent home and finally got to hook my record player up. Halfway through the second song, the system made a loud pop and the meters dropped. I didn't smell anything and I've since pulled the cover off and inspected everything. I don't see anything burned or fried looking but I did check the pico fuses on each board and the right channel ones are toast. I hooked the amp back up to the DBM+Variac and took some measurements at 60V with 10K ohm resistors on the ground/output test points. B+ at 40.70 and B- at -40.82 but the left output had 38.53v and the right had 0.24v. 12R/11R are also at 0.58v and 0.24v.
I'm not really sure where to go from here. I was thinking of pulling the output transistors and inspecting the back of the boards to see if something shorted there. I made sure none of my solder points were long and that I didn't over-torque the output transistors and checked for chassis shorts between each row but, maybe something got in there somehow, I dunno.
Sorry for the long thread, any help would be most appreciated.
) But that would presumably blow fuses. Any sign of an electrical arc inside the chassis? Generally looks like a small burn mark.
