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previous: Bob I have an amp that rattles/buzzes o... -- 3/6/1998 7:56 PM View Thread

Re: 5881 problem

3/7/1998 1:13 PM
R.G.Re: 5881 problem
Three possibilities:  
(a) the tubes are bad/microphonic and they themselves are resonant there  
(b) the tubes are microphonic and not resonant, bu the case/chassis is resonant and only that frequency gets back to the tubes.  
(c) Something else in the chassis is resonant/microphonic, and getting this back to the outputs.  
In either case, try a new set of tubes. Even if this does not fix the problem, you're not just stuck with tubes; you'll need them eventually. You might find a kindly tech to try some new ones temporarily. If the tubes don't fix it, tighten EVERY tightenable fastener on the chassis, and then start chasing cabinet/chassis resonances.