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previous: Bruce Ha! Ha! Me too Dave. :>) -- 8/25/1999 9:20 AM	View Thread

Re: cap across pot mod

8/25/1999 9:55 AM
Steve A.	Re: cap across pot mod to Bruce and Dave: A 100k to 470k resistor in parallel to a bright cap on a guitar volume control makes sense. But I was going on the assumption that evan did mean a 100R to 470R resistor and that it would obviously have to go in series with the bright cap (a 100 ohm resistor across the ungrounded terminals of a 250k to 1M pot would essentially convert it into a two terminal variable resistor- but then again maybe that is what he is doing...) As long as you have your calculator out maybe you can analyze this Ck setup I've been using a lot (for an intermediate gain stage that can't handle the full boost of a Ck cap without going into fizzy distortion): a 1.0uF poly cap, but with a 3.3k resistor in series on the leg to ground. Rk is 1.5k and Rp is 100k. My ears tell me that the frequency is roughly the same as a 1.0uF cap across a 1.5k resistor, only that 3dB gain is cut back a bit... Thanks! Steve Ahola

8/25/1999 9:55 AM

Steve A.

Re: cap across pot mod

to Bruce and Dave:

A 100k to 470k resistor in parallel to a bright cap on a guitar volume control makes sense. But I was going on the assumption that evan did mean a 100R to 470R resistor and that it would obviously have to go in series with the bright cap (a 100 ohm resistor across the ungrounded terminals of a 250k to 1M pot would essentially convert it into a two terminal variable resistor- but then again maybe that is what he is doing...)

As long as you have your calculator out maybe you can analyze this Ck setup I've been using a lot (for an intermediate gain stage that can't handle the full boost of a Ck cap without going into fizzy distortion): a 1.0uF poly cap, but with a 3.3k resistor in series on the leg to ground. Rk is 1.5k and Rp is 100k. My ears tell me that the frequency is roughly the same as a 1.0uF cap across a 1.5k resistor, only that 3dB gain is cut back a bit...

Thanks!

Steve Ahola

Replies:

Dave H. Steve,Bypassing Rk ... -- 8/25/1999 1:21 PM