Vibrolux 5F11 - Selenium Rectifier

[greg]

I am in the process of building a 5F11 Vibroluxe and am wondering about the Selenium Rectifier listed on the circuit. All of the amps I have built are cathode biased, so I have no experience in this area.

Should I simply replace it with just a 1N4007 or does it make more sense to set it up to be variable? If so, can you point me to a schematic which would help out - and also, what should it be biased to?

Thanks,

Greg

[Bruce / Mission Amps]

I am in the process of building a 5F11 Vibroluxe and am wondering about the Selenium Rectifier listed on the circuit. All of the amps I have built are cathode biased, so I have no experience in this area.

Should I simply replace it with just a 1N4007 or does it make more sense to set it up to be variable? If so, can you point me to a schematic which would help out - and also, what should it be biased to?

Thanks,

Greg

Yes, just use a Si 1N4007 and tweak the resistors in the bias supply, to compensate for the better diode, to get proper bias voltage.

[Enzo]

Any selenium rectifier you can find will be 50 years old or more, they are leaky, and if one ever burns up on you, it creates a stink you will remember the rest of your life. A sort of burning rotten cabbage smell.

Please, use a 1N4007.

[greg]

Does this amp need to be fixed bias?

Thanks,
Greg

[Bruce / Mission Amps]

Well, no. But for best results (the vibrato circuit is modulating the power tube's bias voltage to get the "power tube" vibrato)... so, fixed bias works the best.
Both the 5E11 and the 5F11 are fixed bias.

[Dave Curtis, dB AudioTech]

Not just a bad smell, but toxic.