oddball compressor circuit

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pucho812

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Stumbled upon this the other day. I am not quite sure what is going on.  I do know from reading that the 1M pot controls speed and the 25K pot controls how much compression. I can assume that speed would be attack time and that amount of compression would be ratio. But I am still baffled as to how this works ???
 

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pucho812 said:
Stumbled upon this the other day. I am not quite sure what is going on.  I do know from reading that the 1M pot controls speed and the 25K pot controls how much compression. I can assume that speed would be attack time and that amount of compression would be ratio. But I am still baffled as to how this works ???
Signal is buffered by 1st triode (cath-follow), then rectified by the 2nd triode (diode-connected), charges capacitor ; release time adjusted with 1Meg pot. Rectified signal goes to both sections of the 2nd tube. First half again a cath-followthat drives the 25k pot. The voltage between grid and cath is used to drive the last triode that is used as a voltage-controlled resistor that shunts signal coming from the 470k (the horizontal one). The output signal is high-Z so needs buffering.
The whole circuit being unbalanced, results in thumps.
 
abbey road d enfer said:
Signal is buffered by 1st triode (cath-follow), then rectified by the 2nd triode (diode-connected), charges capacitor ; release time adjusted with 1Meg pot. Rectified signal goes to both sections of the 2nd tube. First half again a cath-followthat drives the 25k pot. The voltage between grid and cath is used to drive the last triode that is used as a voltage-controlled resistor that shunts signal coming from the 470k (the horizontal one). The output signal is high-Z so needs buffering.
The whole circuit being unbalanced, results in thumps.

thanks :) where would I me without this place. 
 
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