[sdiy] Variable Slope Filter / Phaser

[JH.]

I think about making PCBs for this.

A mean little module from my JH-3 Modular.

6 filter poles, realzed with OTAs and combined FET / Bipolar buffer stages.

Variable Slope function for 6-pole VC LPF.
Voltage controlled Pole Spread for Phaser mode.
Zeroes switcahbel in pairs, i.e. a lot of combinations of all pass and low 
pass stages. Positive and negative feedback. Positive and negative wet/dry 
mix. Rather special overdrive behaviour (Dirty!), and (IMO) pleasant way of 
breaking into oscillation.

Old picture (from JH-3): 
http://electro-music.com/forum/phpbb-files/jh3_varislope_phaser_887.jpg

Demo 1 (Arpeggio from OB-8, with delay and reverb. First few seconds dry - 
then playing with phaser.):
http://electro-music.com/forum/download.php?id=16715

Demo 2 ( This is something I recorded a few years ago. I don't remember all 
the details. But it was a Split on the OB-8, bass sound on left hand and 
organ sound on right hand, and the whole thing was processed with the 
Variable Slope Phaser / Filter to get that "pulsating" sound.
Lots of delay and reverb as well, obviously.):
http://electro-music.com/forum/phpbb-files/oct_06_zwischenstand_edit_189.mp3

JH.