• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

6BQ5 Sweet Spot?-Charts for other than 250 Screen Volts?

I'm working on designing a SE 6BQ5 amp. I have built several from old Magnavox amps (see attached) but when compared to commercially available SE 6BQ5 Amps there output is a little weak.

Do you know where I can find charts on this tube with different screen voltages?

I have looked at a lot of different schematics. Most set the screen voltage at other than 250 Volts.

Perhaps a simpler question is what would be the (Sweet Spot) optimum Plate, Screen and Grid Voltages?

I'm using 5k-8 outputs (Edcor GXSE10-8-5K). I can go up to about 300V on the plate. I want to stay around 10 watts at the plate. The rating on my power Tx is 100ma. The other tubes I plan to use are a 6CA4 and a 6CG7

Thanks for any input



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