Right Channel Issues

[tdogzthmn]

Got my Stereomour in today and fired it up only to notice that the right channel had hum and had significantly lower volume.  The Tube on the right had much less blue glow compared to the left.  I swapped tubes to check that and was able to get the right channel to sound ok until I tapped the top plate which killed the sound on the right.  I found one unsoldered connection on the tube socket which I soldered but am still having issues.  This amp was assembled at Bottlehead and was recently shipped from another owner so I know it was working before shipping.  Is there another connection around the tube socket which I should look at or just reflow all the solder points on the right tube?

[Paul Birkeland]

Start with voltages and resistance checks.

[Doc B.]

Suggest you take the voltage measurements laid out in the manual and share anything that is not correct.

[tdogzthmn]

I tried tightening the contact plates in the pins sockets with some needle nose pliers and it seems to have fixed the problem.  The tubes are both giving off the blue glow and both channels are playing strong!  If the problems reoccurs I'll check the voltage measurements but all seems ok for now, thanks!

[Grainger49]

Also, I have to ask, did you use the hum balance pot?You didn't mention it and it can make a significant difference.

[tdogzthmn]

Once the connection was restored to the pins on the right socket, the hum was gone and the amp is running with a silent background.