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.
G
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.
G