Hello, Patrick
You may be getting close. Definitely swap the front end tubes from channel to channel. Make sure you mark them V1A, V2A, V1B,V2B etc to keep things straight. You may have to work through the whole tube complement to find a culprit.
Bonding of the receptcle frame to the box is really not good enough IMO the box is oxidized cadmium plated and you are trying to achieve a good ground...I'd add a wire from the ground terminal of the receptcle to the box if it were me...you still need to check the other end out with an electrician...this point may be minor if there is no ground at the front end anyway.
Try a sheilded ac supply cord from Belden or Volex(P/N 17604) They cost about $15.00 for a 14gauge type from any of the supply houses like Allied Electronics etc.They give similar performance to some of the high priced highend types for a fraction of the cost.
Lift the ground with a cheater to note the result
Try turning down your gain or if you are really adventurous move your equipment around to see the result...clean your contacts!
Jim has always responded to me...he may be busy or sometimes the spam filters don't let you through. You can give a call otherwise.
You may be getting close. Definitely swap the front end tubes from channel to channel. Make sure you mark them V1A, V2A, V1B,V2B etc to keep things straight. You may have to work through the whole tube complement to find a culprit.
Bonding of the receptcle frame to the box is really not good enough IMO the box is oxidized cadmium plated and you are trying to achieve a good ground...I'd add a wire from the ground terminal of the receptcle to the box if it were me...you still need to check the other end out with an electrician...this point may be minor if there is no ground at the front end anyway.
Try a sheilded ac supply cord from Belden or Volex(P/N 17604) They cost about $15.00 for a 14gauge type from any of the supply houses like Allied Electronics etc.They give similar performance to some of the high priced highend types for a fraction of the cost.
Lift the ground with a cheater to note the result
Try turning down your gain or if you are really adventurous move your equipment around to see the result...clean your contacts!
Jim has always responded to me...he may be busy or sometimes the spam filters don't let you through. You can give a call otherwise.