Hi All,

I am having problems with low gain on channel 1.  I understand that channel 1 should be slightly quieter than channel 2, but I'm talking way quieter.  Channel 1 isn't loud enough to play any type of club, or even a band practice.  I've checked the plate voltages for the tubes and everything is in 5% tolerance of spec.  I've checked the pots to make sure they are working properly.  Both the 1.5 K resistor and the 220 K resistor are within tolerance.  I've also replaced all the preamp tubes.  I can't think of anything else, short of changes to component values to increase gain.

Does anyone else have a severe gain difference between channels?  Anyone have suggestions on what to change or test?  The amp has a great sound, but at this volume is useless.  Any help is appreciated.  Thanks!

well i was talking to nik, since all the voltages check out its probably not any of the resistors or caps.  most likely a wiring issue.  maybe a cold solder or a bad ground that's attenuating the signal.  i'm in the process of re-dressing the amp anyway, so any wiring issues should get fixed.  i built the amp 2 years ago and was new to the field.  i've since learned a lot about tubes and wiring, so i figured this amp needs to get updated.

i suspected the volume pots could be acting up, but they checked out.  i am replacing them anyway with PEC pots as part of the re-dress.  i'm currently desoldering the amp right now.  i'll keep you guys updated on what happens.  thanks.