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previous: Jim Wheeler OK - OK apparently it was a really ... -- 5/15/2000 9:15 PM

Re: VibroChamp Tremolo

5/15/2000 9:37 PM
Randy	Re: VibroChamp Tremolo Those amps were not cathode biased, they used a fix bias supply, that is something around -45 volts. The oscilator would vary this voltage to create the effect. The current at this point in the circuit is very low. The cathode was directly grounded . In a single ended design , cathode biased , like the champ, the cathode current is high and full time. I would be concerned about building an oscilator that varies the cathode current. It certainly would need to be of a differnt design than the brownface. But hey, experiments are cool.

5/15/2000 9:37 PM

Randy

Re: VibroChamp Tremolo

Those amps were not cathode biased, they used a fix bias supply, that is something around -45 volts. The oscilator would vary this voltage to create the effect. The current at this point in the circuit is very low. The cathode was directly grounded .

In a single ended design , cathode biased , like the champ, the cathode current is high and full time. I would be concerned about building an oscilator that varies the cathode current. It certainly would need to be of a differnt design than the brownface. But hey, experiments are cool.

Replies:

Peter S Some of the old Ampegs use this typ... -- 5/15/2000 9:41 PM
Rick Erickson I've always thought the Vibro-Champ... -- 5/15/2000 11:31 PM