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previous: pumpstein Jon,thanks for the ... -- 10/18/2000 6:40 PM

Re: 7355 tubes

10/18/2000 9:22 PM
jon	Re: 7355 tubes P, I'm running in the high 300's, cathode biased kinda like an Ampeg Gemini 1. I wanted to see how close they were to 7591's in this environment. The circuit I pulled them from was in the high 400's, fixed bias. Gonna try one like that soon. You should be able to get the 6AV5/6AU5's dirt cheap. they'll handle in the low 500's on the plates, just keep the screens way low, like 175 or so. I've yet to do one with a regulated power supply, getting low voltage screen current in a guitar amp was a bit of a challenge for me. I've done 2 so far, one with a dedicated tranny/filtered low voltage suply for the screens. the other used a huge dropping resistor and a choke downstream from the preamp. i love this amp, as it's really responsive to pick attack. Tried to repeat the design with slightly different components, and the power supply kept on crashing with application of signal. next time gonna d0o a regulated power supply, ala Bogen, now that I understand them a bit better. see ya, Jon PS Dunno anything about EL37's.....except that they're scoffed up by the hi fi guys.

10/18/2000 9:22 PM

jon

Re: 7355 tubes

P,
I'm running in the high 300's, cathode biased kinda like an Ampeg Gemini 1. I wanted to see how close they were to 7591's in this environment. The circuit I pulled them from was in the high 400's, fixed bias. Gonna try one like that soon.

You should be able to get the 6AV5/6AU5's dirt cheap. they'll handle in the low 500's on the plates, just keep the screens way low, like 175 or so. I've yet to do one with a regulated power supply, getting low voltage screen current in a guitar amp was a bit of a challenge for me. I've done 2 so far, one with a dedicated tranny/filtered low voltage suply for the screens. the other used a huge dropping resistor and a choke downstream from the preamp. i love this amp, as it's really responsive to pick attack. Tried to repeat the design with slightly different components, and the power supply kept on crashing with application of signal. next time gonna d0o a regulated power supply, ala Bogen, now that I understand them a bit better.
see ya,
Jon

PS Dunno anything about EL37's.....except that they're scoffed up by the hi fi guys.

Replies:

pumpstein "...I'm running in the high 300'... -- 10/18/2000 10:55 PM