In Reply to: RE: 6V6 Amp Feedback posted by Eli Duttman on December 30, 2016 at 11:36:39:
I've heard about that with the reissue 7591s, but I haven't worked with those. Is this a grid emission problem? The grid drifts positive when the resistor is too large?
Doing this "by the book" creates a couple other issues besides the need for greater drive current. The coupling cap needs to be made considerably larger to maintain identical frequency response. And there's more risk with a smaller grid resistor that the signal will "see" the decoupling cap in the bias circuit.
Maybe I've just been lucky making these changes in the past. If you know, how far away from the manufacturer's specs did Fisher push the grid resistor?
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- RE: 6V6 Amp Feedback - Triode_Kingdom 12/30/1612:48:38 12/30/16 (12)
- RE: 6V6 Amp Feedback - Jim McShane 14:34:44 12/30/16 (10)
- RE: 6V6 Amp Feedback - Triode_Kingdom 00:09:18 12/31/16 (9)
- RE: 6V6 Amp Feedback - Jim McShane 14:05:09 12/31/16 (7)
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- RE: 6V6 Amp Feedback....Start Over Please - sony6060 07:58:16 01/3/17 (3)
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- RE: 6V6 Amp Feedback....Start Over Please - sony6060 07:42:40 01/4/17 (0)
- RE: 6V6 Amp Feedback - PakProtector 08:24:53 12/31/16 (0)
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