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previous: friday Is a Fender Champ considered to be ... -- 10/11/2000 6:30 PM

Re: FENDER CHAMP - CLASS A?

10/12/2000 3:22 AM
DanF	Re: FENDER CHAMP - CLASS A? Yes. The power tube (or tubes) in Class A amps amplify the entire signal. If you picture the audio signal as a sine wave, each power tube in a Class A amp will conduct the entire wave. In a Class B amp, two power tubes "share" the task of powering the signal - one conducting the upper half of the wave, the other conducting the lower half. In Class AB amps, the tubes do something in-between: each of the two power tubes conduct more than half of the wave -- but at the peaks of the wave only one tube is carrying the signal. In an amp with a single power tube, like the Champ, one tube needs to conduct the entire wave - therefore, Class A. (Many Class AB and B amps use 4 power tubes, working in pairs to conduct the upper and lower halves of the wave.) There are much better descriptions, with diagrams, on the web. Check www.aikenamps.com or the AX84 pages. - Dan

10/12/2000 3:22 AM

DanF

Re: FENDER CHAMP - CLASS A?

Yes. The power tube (or tubes) in Class A amps amplify the entire signal. If you picture the audio signal as a sine wave, each power tube in a Class A amp will conduct the entire wave. In a Class B amp, two power tubes "share" the task of powering the signal - one conducting the upper half of the wave, the other conducting the lower half. In Class AB amps, the tubes do something in-between: each of the two power tubes conduct more than half of the wave -- but at the peaks of the wave only one tube is carrying the signal.

In an amp with a single power tube, like the Champ, one tube needs to conduct the entire wave - therefore, Class A.

(Many Class AB and B amps use 4 power tubes, working in pairs to conduct the upper and lower halves of the wave.)

There are much better descriptions, with diagrams, on the web. Check www.aikenamps.com or the AX84 pages. - Dan