Just Got A SOB And Have Some Questions

[cwofnorthandover]

Im new and i just got a SOB and when i strum i get random crackling sounds it has a ev speaker in it i dont think it has been used in 20 years so looking for tips on tubes also curious about the ground switch on the back left or right? Also the presence doesnt seem to work.Looking to find out about where the serial number is and where i could find schematics.Any help is good help thanks can't wait to crank this up!

 

[Don]

Hard to say what the crackling sound is. Could be dirty jacks or tube sockets, screen grid resistors, or something else. Does the ground switch have a middle position? Put it there if it's quiet.
Search the web for schematics. They're out there.

 

[stokes]

Hasnt been used in 20yrs? A cap job should be done.The crackling is very likely dirty tube sockets.I would have a capjob and general cleaning/service done before thinking about tubes.Hard to guess what is with the presence,perhaps someone disconnected it.