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previous: Marco "best" master volume control? -- 11/19/2000 12:52 PM View Thread

Re: "best" master volume control?

11/21/2000 8:45 PM
Rick Erickson
Re: "best" master volume control?
"I'm searching for the "best" MV control in a marshall style amp."
The "best" MV circuit is the one YOU like. I have heard decent sounding amps with all of these circuits. My least favorite is the Matchless style, the Ken Fisher mod will lose bias to the power tubes if the pot gets dirty and/or opens. A pre p/i MV needs a well designed preamp before it. The post p/i dual pot MV requires the least modification to a relatively stock amp.  
An interesting twist to the standard post p/i dual MV is to swap the input & output leads to the MV. This runs the output of the p/i to ground creating more distortion at lower settings. Bedrock used this circuit in their amps. The production model I saw used a dual 500K Lin. pot. I imagine anything from 250K to 1M would work fine, although 250K will load the circuit a bit even when turned all the way up.  

Shysterfish Bedrock MV -- 11/22/2000 12:55 PM