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previous: Steve Slick Ray,Yeah, it's Marl... -- 5/25/2000 8:08 PM	View Thread

Re: Question about a Crate VC5115 bias adjustment

5/25/2000 9:50 PM
Ray Ivers	Re: Question about a Crate VC5115 bias adjustment Steve, Sorry - I got shanghaied by the 'derived from B+' part of your post and drifted away from the larger question. Yes, I would have to say that any amp can be biased, or modified to do same if not equipped stock with the capability, except maybe a Class B triode output stage, which usually has no bias at all. I've seen posts here that talk about adjustable cathode-bias, even. Is there anything that the Ampage folk cannot do? - surely not. All of which doesn't really help you with your situation. I would suggest all the usual don't-have-a-schematic Brownian activity - checking for the presence of cathode resistors and/or tracing backward from the output tube grids if a negative voltage is found there, to the nearly-inevitable voltage divider that will be tweaked. In the meantime, I will check for Crate schematics, and if I find any, you'll be the first to know. Marleyman - thanks for the post. Remember - if your tech smokes your amp, he owes you a new one. == ;~> Ray

5/25/2000 9:50 PM

Ray Ivers

Re: Question about a Crate VC5115 bias adjustment

Steve,

Sorry - I got shanghaied by the 'derived from B+' part of your post and drifted away from the larger question. Yes, I would have to say that any amp can be biased, or modified to do same if not equipped stock with the capability, except maybe a Class B triode output stage, which usually has no bias at all. I've seen posts here that talk about adjustable cathode-bias, even. Is there anything that the Ampage folk cannot do? - surely not.

All of which doesn't really help you with your situation. I would suggest all the usual don't-have-a-schematic Brownian activity - checking for the presence of cathode resistors and/or tracing backward from the output tube grids if a negative voltage is found there, to the nearly-inevitable voltage divider that will be tweaked. In the meantime, I will check for Crate schematics, and if I find any, you'll be the first to know.

Marleyman - thanks for the post. Remember - if your tech smokes your amp, he owes you a new one. == ;~>

Ray