Tube DIY Asylum

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Original Message

RE: Grid Stopper Resistors.

Posted by Tre' on January 7, 2017 at 12:01:51:
"What about low gain such as a 6SN7 tube & would a grid stopper alter the sound?"

If a grid stop resistor alters the sound (other than stopping RF oscillation) then it's value is too high.

The value of a grid stop resistor and the value of the tube's Miller capacitor forms a low pass filter.

The -3db point of that filter should be at least 200kHz. That will stop RF but let all the music pass without shifting the phase.

In practice you only what to use enough resistance to stop the oscillation.

Tre'