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previous: Troy Any opinions of envelope filters fo... -- 3/16/2000 12:13 AM

Re: Envelope Filters for Bass

3/16/2000 3:12 PM
Mark Hammer	Re: Envelope Filters for Bass Envelope filters for bass need to have: 1) either less sensitivity, or better control over sensitivity, since bass PU output tends to be higher 2) a way of shifting the filter range downward (where the first coupla harmonics are for bass), or a lower range to start 3) a fast attack or way of altering the attack to let bass be as percussive as it can Most available pedals will give you one of these but not necessarily all 3. In many cases, you'll have to mod what you get. I threw together a couple of Dr. Q's recently, from the schematic posted at AMZ (www.muzique.com), and it provides good value for time invested, but would need to be modified for bass. Specifically, the mods would likely involve changing the two .0047 caps that form the filter for .0082 or .01uf caps, and tweaking the sensitivity by either: a) the trimpot setting, b) replacing the 2.2Meg resistor with something a bit smaller (say 1.8meg), or sticking a fixed rsistor in series with the input of the sensitivity control (say 22k). The Qtron+ and Bassballs are optimized for bass, and if you can find an MXR Envelope filter, so is that. I specify the Q-tron+ because it has attack-time control.

3/16/2000 3:12 PM

Mark Hammer

Re: Envelope Filters for Bass

Envelope filters for bass need to have:
1) either less sensitivity, or better control over sensitivity, since bass PU output tends to be higher
2) a way of shifting the filter range downward (where the first coupla harmonics are for bass), or a lower range to start
3) a fast attack or way of altering the attack to let bass be as percussive as it can

Most available pedals will give you one of these but not necessarily all 3. In many cases, you'll have to mod what you get. I threw together a couple of Dr. Q's recently, from the schematic posted at AMZ (www.muzique.com), and it provides good value for time invested, but would need to be modified for bass.

Specifically, the mods would likely involve changing the two .0047 caps that form the filter for .0082 or .01uf caps, and tweaking the sensitivity by either: a) the trimpot setting, b) replacing the 2.2Meg resistor with something a bit smaller (say 1.8meg), or sticking a fixed rsistor in series with the input of the sensitivity control (say 22k).

The Qtron+ and Bassballs are optimized for bass, and if you can find an MXR Envelope filter, so is that. I specify the Q-tron+ because it has attack-time control.

Replies:

Mark Hammer Oops, almost forgot. -- 3/16/2000 4:50 PM