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high bias on '65 Princeton Reverb; BAD?

11/21/1999 8:43 PM
rb	high bias on '65 Princeton Reverb; BAD? Hello; I would appreciate comments. I checked the bias on my 1965 fender princeton reverb (w/ a multimeter and bias probe) and was disturbed to find it was between 36 and 38 ma (on the 2 tubes). I understand bias on 6V6GTs should be set between 20-30 ma. Since there is no adjustable bias "pot" I would have to take the amp to a tech to get it set (I am not a "techie! if it is a simple de-solder/solder job I might consider it, however). Are there any other problems associated w/ "too high" bias other than shortened tube life? Is there danger of damage to other components? Is my rhythm sound (run about 3-4 on volume) being affected (ie more distortion?) Thanks for your comments/advise.

11/21/1999 8:43 PM

high bias on '65 Princeton Reverb; BAD?

Hello; I would appreciate comments. I checked the bias on my 1965 fender princeton reverb (w/ a multimeter and bias probe) and was disturbed to find it was between 36 and 38 ma (on the 2 tubes). I understand bias on 6V6GTs should be set between 20-30 ma. Since there is no adjustable bias "pot" I would have to take the amp to a tech to get it set (I am not a "techie! if it is a simple de-solder/solder job I might consider it, however). Are there any other problems associated w/ "too high" bias other than shortened tube life? Is there danger of damage to other components? Is my rhythm sound (run about 3-4 on volume) being affected (ie more distortion?) Thanks for your comments/advise.

Replies:

Rob W. Hello!First you mus... -- 11/22/1999 12:43 AM