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Marshall Bias Feed Resistors

8/14/1998 4:23 PM
Derrick Marshall Bias Feed Resistors
What is the mod to change the 220k bias feed resistors to 100k in a Marshall supposed to do? Also, what is it supposed to stop/or protect.......Exactly? I experimented with mine and hear no differance.  
8/14/1998 5:13 PM

It is meant to change the bias voltage when changing to different tubes. 220k for EL-34's and 150k for 6550's. Make sure you bias your amp afterwards, or you may destroy your tubes.
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