Genalex Gold Lion KT-77 Compatibility Question


I love the sound of the Genalex KT-77's in my push-pull EL34 amp but I have now twice had the right channel tubes die on me within a 4-6 month period. After installing another quad in my amp I noticed, for the first time though it's certainly possible I missed it with past tube sets, that the two right hand tubes were glowing noticeably brighter than the two right hand tubes. So obviously, I think, the right channel is running hotter. I have not had this issue with any other tubes I have used and the amp recently had some minor service and is in perfect working order. So are these tubes simply not ideal for my amp? And generally speaking though they are supposed to be a drop in replacement for EL34 tubes are there differences in electrical or performance parameter between a typical EL34 or 6ca7 tube? I love the sound of these tubes in my amp but it's frustrating and annoyingly expensive to replace half a quad every 4-6 months or so, any thoughts from any of our more tech minded posters?
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It's Deja Vu push-pull amp and you can't adjust the bias not sure if its fixed or self adjusting.
Does your amp have bias trim controls? Sounds like the right channel bias is set too high.
Your amp most likely has cathode-bias whereby the cathodes are connected to ground via a fairly large value resistor. The current flowing through that resistor causes a voltage drop which the grid "sees" as a negative voltage relative to the cathode. This is the bias voltage. If the value of this resistor is lower than it should be, the output tubes will run at a higher current.

I agree with the suggestion to take the amp back to Vu, but if you don't live in the DC area any competent tech should be able to figure this out.
Thanks for all the responses I will drop by and see Vu I just thought this issue might be more tube related since it only occurs with the KT-77s and no other tubes. If it's a difference in channel bias on the amp why haven't I had an issue with either EL34 or 6ca7 tubes?