• 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.

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I'm building a SE EL34 amp that I designed and I managed to get a pair of Magnequest TFA 204 transformers for it. I have a small problem in that the transformers will only handle about 60mA of current through the primary before they start saturating so I will have to bias the EL34s at about 55mA or so to use them. I went looking around the net to see if I could find a design that ran them at that low of a current and came across this:

http://www.angela.com/catalog/how-to/EL34.gif

You'll notice that he is using a 880 ohm resistor on the cathodes of the EL34s and is showing 28 volts on the cathode which would of course mean that he is running a bias of about 32mA. This seems really low to me. Has anyone built this design or have experience with running EL34s at a lower than optimum bias? Thanks.

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