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previous: Rick Erickson Dave, Aparently I m... -- 11/24/2000 10:52 PM View Thread

Re: Bedrock MV

11/27/2000 8:38 PM
Steve A.
Re: Bedrock MV
... one way sends the wiper to the power tubes, the other has the wiper connected to the output of the p/i, running the p/i's plates (through the coupling caps) toward ground. The latter method produces a good bit more distortion than the former.  
    I'd been wondering about that! Dan Torres' post-PI MV is wired up the second way while Bruce Collins always recommended the first way (not unlike a stereo volume control). Diff'rent strokes for diff'rent folks, I guess! If you are looking for a lot of distortion at lower settings from a vintage design then I guess you would want to go with Dan's design. (I believe that the Trainwreck Papers show the MV wired up the first way.)  
Steve Ahola  
P.S. I really hadn't noticed the problem with NFB either! Then again I usually use a large NFB resistor like 22k to 56k. Sometimes I think that KO'C is a bit too much into theory than reality... FWIW some people who have tried out the amp designs in his books think that they are a bit on the buzzy side of things. "You have distortion... what ELSE do you want???" Well, good tone would be nice...   ;)   Of course all of his suggestions do make good food for thought, which will presumably be digested and modified for one's own tastes, rather than just regurgitated whole... Speaking of which, I hope that everybody had a nice Thanksgiving dinner!

Bruce First off the only reason to do thi... -- 11/27/2000 9:46 PM