10 years! Seems that it´s time to replace the tubes, no doubt about that.
Tube Question
I have an amp that has Russian Tubes. This amp purchased in the 90's has always had a hum to it which when playing music isn't heard. I'm thinking of buying 1 6SL7 and 1 6550EH tube to swap out and see if I can find if one of the tubes is the problem. The 6SL7 is Sovtek and the 6550EH is electro-harmonix. Should I replace with a similar tube from another company or continue with the same company? Is this approach to finding the problem sensible or a waste of time?