Losing left channel/high voltages post-Speedball install [Resolved]

[Paul Birkeland]

Sure, you could give that a try.  It may also be that the pins are a bit oxidized.  Just pressing them into a scotch-brite pad will often renew the pins a bit.

[aravenel]

Ah, good tip, that let me get a steady reading at least. Still open circuit b/t 5 and 9, reading 5.7 ohm b/t 4 and 9. Sound like a bad tube?

[Paul Birkeland]

On a very, very rare occasion the connections to the pins can break off inside the tube.  I think I've seen this maybe twice in twenty years, so it's not impossible, but still extremely likely.  Don't ask me how much time I spent trying to clean those pins before looking closely inside the glass and seeing the break!

[aravenel]

Pulled out a magnifying glass and dont see any obvious breakages in there, but all the same... It seems like the obvious things have failed, so might as well try swapping the tube, at least rule that out.

[aravenel]

Update: New 12AU7 tube came in yesterday. Voltages are now in line, and a listening test has the left channel back to where it should be. I much appreciate all the help--super excited to have my amp back up and running!