fred.violleau wrote: ↑Mon Dec 18, 2023 9:36 pm Got a few questions on the schematic posted by Bepone vs Aaron's original, mostly on the 4th stage of the drive channel, on Aaron's schematic there is a 45k resistor going into the coupling cap and then into another 45k resistor, when on bepone's schematic, it seems to be closer to the original JCM800 with 0.005uf coupling cap going into the 470k divider resistors. I don't have a simulator to see what frequencies these two setup would affect. can one of you elaborate on this ?
PXL_20231218_211012184.jpg
Bepone have you tried to replace V1 socket ? It seemed you had trouble with it during the build.
47k is not possible , 470k is standard divider in hi gain circuits like marshal soldano/ after mesa and so on..
V1 socket replaced, also nothing changed.. remain only gain potentiometer and after that if the problem persists.. i will go on direct socket build all the components in the air.. to avoid the press board, and if that solve the problem, the the fault is in the board i try to believe that is not because i cleaned and varnish eveything before, we will see..
I have another hi gain build in progress so im concentrated mosty there, on this build i give only 10 minutes per day to not loose much time and motivation