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RE: KT-88 bias in MB-3045

Posted by geraldm121 on June 18, 2009 at 13:45:17:
You sound like exactly the person I need to talk to. I too have owned these amps since the the late 70's.I did the basic (resistor changes and additions) tied triode modification per the 1st page of the LUX service bulletin as I wanted to stay as true as possible to the original configuration and hopefully the keep the sound I had been so happy with. The following pages of the bulletin seemed to relate only to a mod that reconfigured the amp into a pentode circuit. Kt 88's seemed the way to go as availability should be good for quite some time and I hate changing something I have been happy with. Also I have used Kt88's as triodes before successfully.
The issue as I mentioned above is that with the current Sovetek KT88s I am using the sound is rather shrill. It could just be the sound of the Soveteks or it could be that they are under biased. I wondered what the maximum safe bias would be for the Soveteks? Unfortunately I only have the Sovetek KT88's, some SED 6650's and a pretty well used set of (my all time favorite) GE 6550's at this house. I do have a set of the Genelex (Russian)re-issues and a couple sets of new Shuguang KT 88's at my vacation home.
So with all that said any suggestions or comments?

Regards, Jerry