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What is meant by scratchy inputs?
I installed the VRM kit in my Deluxe, but left out the caps supplied to deal with scratchy inputs.
How would I recognize this - what am I listening for?

When you dial down the VRM to low power the pots on your guitar can become scratchy as you rotate them. This is due to tiny amounts of voltage accross them.

Yes, I did the same as you originally and left the blocking caps out. It took a few days of playing around before I realized that I was getting some scratchiness on the volume pots of my guitar. I later went back and installed the blocking caps to eliminate the problem.

Wasn't there a mod being discussed for the VRM to add a low end limiting resistor so it wouldn't go into the problematic range? I would think that would be simpler to implement than the caps on the inputs.

Joe G

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Some assembly required,
Brain sold separately...

The problem is that if you want to dial the volume down a lot, you will go into this problematic range. So the answer is to use the DC blocking caps at the amp input. An even better solution is to have the VRM only regulating the PI and PA sections of the amp, so the preamp stays at normal voltage, which helps maintain clarity at very low volume levels, as well as eliminating the scratchy pot issues. Unfortunately, the trade off is a slightly more complicated power supply arrangement. So a lot of folks just stick to the input cap instead.

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Great tones come in small glass jars!

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