Thanks...I'll dig up the JJs and see what' up with them. I did drive straight into the PI...~10Vrms edge of clipping with 760mVrms sine wave. Av = 13.rooster wrote:jaysg - OK, this explains everything to me. Either try some other tubes that are much colder or change your bias resistors. Easily, running that quad (@ 8volts!!), you can change you bias resistors to 150 X2 and still be under 11 volts. I would do this in a heartbeat, what have you got to lose?
JJs: 26W...cathodes idle at 9.3V...the Saratovs sound better though...have to order some resistors. Will I be able to get full power from the Saratovs this way?
Thanks to all who helped and took an interest. I didn't notice the volume drop when I put the Saratovs in...never thought twice about it. I wouldn't have guessed there would be that much variability.