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I posted this on another forum, but so far I haven't had any leads. 
About a month ago, I finished building my twin reverb clone. It was based on a hoffman AB763 layout. It sounds great and everything works fine just the tremelo is pretty weak. So I figured I would get around to changing the resistor size in the circuit. There was also a buzzing. It goes up some with the volume and really gets louder when increasing the reverb.
I fiddled for a couple of days with trying to solve the buzzing. I did learn that you shouldn't run the reverb wire from the pot to the board alongside the main cap wire (two F&T 80uf in series) and when I moved it and tucked it above the pots that cut down on the reverb buzz substantially. Then I decided to try what fender did in my BMR and my Dual showman reverb. i coiled a wire around the cap wire and grounded each end to the chassis and that got rid of just about all buzz. You can hardly hear it now. I went ahead did a tremelo mod to give more oomph.
the last problem I can't solve is that the wiring from V4 is microphonic. You can pluck the wires and it sounds like guitar strings over the speaker.
I have resoldered connections, I have replaced wires. Of course I have tried 4 different tubes to no avail. I replaced the tube socket. i removed the wiring from being wrapped around the lugs to going into the lugs. I cannot solve the cause. I have shortened the wires and then replaced tham again in case I shortened them too much. I have pulled the wires up and away from each other to see if one wire is the cause and transferring sound to the others.
The wire going from V4 pin7 seems to be the loudest and also, when I put my finger near it it really starts to buzz like interference. (I know to be careful around high voltage, etc. I just went to push this wire down a little and it wasn't near anything)
When I chopstick the board and components none of them send any sound to the speaker. Just the wires.
I'm about to say the hell with it as the amp works otherwise, but I worked hard trying to get this amp perfect from building the cabinet, the assembly of everything, you know...it'll probably nag me.
any suggestions would be appreciated.
About a month ago, I finished building my twin reverb clone. It was based on a hoffman AB763 layout. It sounds great and everything works fine just the tremelo is pretty weak. So I figured I would get around to changing the resistor size in the circuit. There was also a buzzing. It goes up some with the volume and really gets louder when increasing the reverb.
I fiddled for a couple of days with trying to solve the buzzing. I did learn that you shouldn't run the reverb wire from the pot to the board alongside the main cap wire (two F&T 80uf in series) and when I moved it and tucked it above the pots that cut down on the reverb buzz substantially. Then I decided to try what fender did in my BMR and my Dual showman reverb. i coiled a wire around the cap wire and grounded each end to the chassis and that got rid of just about all buzz. You can hardly hear it now. I went ahead did a tremelo mod to give more oomph.
the last problem I can't solve is that the wiring from V4 is microphonic. You can pluck the wires and it sounds like guitar strings over the speaker.
I have resoldered connections, I have replaced wires. Of course I have tried 4 different tubes to no avail. I replaced the tube socket. i removed the wiring from being wrapped around the lugs to going into the lugs. I cannot solve the cause. I have shortened the wires and then replaced tham again in case I shortened them too much. I have pulled the wires up and away from each other to see if one wire is the cause and transferring sound to the others.
The wire going from V4 pin7 seems to be the loudest and also, when I put my finger near it it really starts to buzz like interference. (I know to be careful around high voltage, etc. I just went to push this wire down a little and it wasn't near anything)
When I chopstick the board and components none of them send any sound to the speaker. Just the wires.
I'm about to say the hell with it as the amp works otherwise, but I worked hard trying to get this amp perfect from building the cabinet, the assembly of everything, you know...it'll probably nag me.
any suggestions would be appreciated.
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