SET Asylum

RE: another commentary...

75.82.52.72

This Post Has Been Edited by the Author

In Reply to: RE: another commentary... posted by commentary on April 29, 2012 at 00:10:35

"Even order distortion is partially cancelled with two cascaded similar tubes (like 6922 -> 6922) as their polarities are inverted with each other."
Maybe you can explain this to me. No one else has been able to.
Let's say we have two hypothetical gain stages. Each with a gain of 10 and having only 2nd order harmonic distortion. Let's say the percentage of 2nd order distortion is 10% (each stage).
If we apply 1 volt of 1kHz to the first stage we get 10 volts of 1kHz and 1 volt of 2khz feeding the second stage.
The second stage amplifier the 10 volts of 1kHz to give us 100 volts of 1kHz.
The second stage amplifies the 1 volt of 2kHz to give us 10 volts of 2kHz.
The second stage distorts the 1Khz and gives us 10 volts MORE of 2khz for a total of 20 volts 2kHz.
The second stage also distorts the 1 volt of 2kHz input signal, to give us 1 volt of 4kHz.
What have I missed?
Thanks
Edit. If you just say "their polarities are inverted with each other" then why wouldn't the fundamental cancel as well?
Yes, each stages output is inverted in relationship to it's own input but that's not germane to the question.
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"

Edits: 04/30/12 04/30/12 04/30/12

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