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previous: Ken Gilbert Something occured to me a few minut... -- 8/21/1999 8:28 PM

Re: Some thoughts on tonal variations due to operating class

8/21/1999 9:21 PM
jeff	Re: Some thoughts on tonal variations due to operating class having built a SE Class A amp (2 6V6's in parallel) and observed first hand - live- so to speak an incredible difference in tone from the more standard P/P Class AB guitar amps, I too have pondered this matter. Since a SE amp does not split the signal and have the 'positive' half amplified seperately from the 'negative' half - as in any Push Pull connnnfiguration I believe that a SE amp sounds 'better' because the output wave is essentially simply a larger version of the input wave- and that a Class A bias yields a more responsive amp, kinda like a fast idle setting in an automobile carburator yields quicker response to the gas pedal ..... It seems to me that the necessary "re-combining" of the positive and negative halves of a signal that has been 'split' by the P/I , where the 0-180 degrees phase "meets" the 180-360 degrees phase, ideally this "meeting" is perfect (thus no cross-over distortion) and we now have our 'original full 360 degree sine wave pumped out thru the speaker, makes an true amplified reproduction of the input signal far less likely that a pure SE amp. so does a Class A bias in a P/P amp sound better because of the dynamics that a "fast-idle" class A biasing yields? And, does true Single-Ended sound better than all of this (IMO because the wave is never split and recombined? Could this be why Audiophiles covet and pay homage to 300B type SE amps?

8/21/1999 9:21 PM

jeff

Re: Some thoughts on tonal variations due to operating class

having built a SE Class A amp (2 6V6's in parallel) and

observed first hand - live- so to speak an incredible

difference in tone from the more standard P/P Class AB

guitar amps, I too have pondered this matter.

Since a SE amp does not split the signal and have the 'positive' half amplified seperately from the 'negative'

half - as in any Push Pull connnnfiguration I believe

that a SE amp sounds 'better' because the output wave

is essentially simply a larger version of the input

wave- and that a Class A bias yields a more responsive

amp, kinda like a fast idle setting in an automobile carburator yields quicker response to the gas

pedal .....

It seems to me that the necessary "re-combining" of the

positive and negative halves of a signal that has been

'split' by the P/I , where the 0-180 degrees phase "meets" the 180-360 degrees phase, ideally this "meeting" is perfect (thus no cross-over distortion) and we now have our 'original full 360 degree sine wave pumped out thru the speaker, makes an true amplified reproduction of the

input signal far less likely that a pure SE amp.

so does a Class A bias in a P/P amp sound better because

of the dynamics that a "fast-idle" class A biasing

yields? And, does true Single-Ended sound better than all

of this (IMO :-)

because the wave is never split and

recombined? Could this be why Audiophiles covet and pay

homage to 300B type SE amps?