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previous: zachary vex cool stuff. i don't know about the... -- 7/29/2000 7:27 PM

Re: Envelope Controlled Filter using tubes?

7/29/2000 9:19 PM
jon	Re: Envelope Controlled Filter using tubes? The multivibrator I've been using for the frequency divider was adapted from an organ circuit, after trying a 1/2 dozen or so that wouldn't give wide enough frequency response. Finally came up with one that will reliably add an octave below(still kinda sawtooth, trying to filter this a bit also) to every note on the guitar fretboard, is nice when mixed with the dry signal, especially with my fretless 6 string. Besides the oscillation I mentioned, needs really high signal voltage, another bug to work out. An attack delay capability would give some nice bowed-type feeling. I've got a few old organ books; have parted out several organs. Tried to adapt some of the neon multivibrator circuits, gave up when they would only handle an octave or so. Something to reconsider. Gotta check out the Markus book...thanx for the lead. I'll have to look into the phosphor panels, ne-2's need around 60 or so volts on them. One major flop was trying to use them in a bucket-brigade setup driving LDR's for a 5 stage univibe-type circuit. Took the easy way out and did it with the varistors, although I don't get the real low frequency sweep going progressively thru each stage that I'd like.

7/29/2000 9:19 PM

jon

Re: Envelope Controlled Filter using tubes?

The multivibrator I've been using for the frequency divider was adapted from an organ circuit, after trying a 1/2 dozen or so that wouldn't give wide enough frequency response. Finally came up with one that will reliably add an octave below(still kinda sawtooth, trying to filter this a bit also) to every note on the guitar fretboard, is nice when mixed with the dry signal, especially with my fretless 6 string. Besides the oscillation I mentioned, needs really high signal voltage, another bug to work out. An attack delay capability would give some nice bowed-type feeling.

I've got a few old organ books; have parted out several organs. Tried to adapt some of the neon multivibrator circuits, gave up when they would only handle an octave or so. Something to reconsider.

Gotta check out the Markus book...thanx for the lead. I'll have to look into the phosphor panels, ne-2's need around 60 or so volts on them. One major flop was trying to use them in a bucket-brigade setup driving LDR's for a 5 stage univibe-type circuit. Took the easy way out and did it with the varistors, although I don't get the real low frequency sweep going progressively thru each stage that I'd like.