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#126519
brock
Participant

The Phaser algorithm isn't going to have the multi-phase LFO control that you're going to need for a 'barberpole' phase shifter.  As I understand it, you have to ramp the all pass filters up (or down) – offset in phase every 45 or 90 degrees.  Then you have to fade each of the filters in & out (triangle wave) to produce the constant rising (or falling) illusion.

You may be able to come somewhat close with a BiPhaz setting, reversed operation, and a very slow Speed value.  Still, I don't think that there's enough there to produce a convincing simulation; even with the secondary S-Mod and D-Mod controls.  I don't have the Phaser algo – yet – but maybe I can try out some settings in under the 5-minute demo time.  I'll let you know what I can come up with.

That's a fascinating proposition for a H9 Special algo feature request, though.  It may be too much of a one-trick pony alone.  But a quadrature-type LFO, with a parallel LFO controlling amplitude, could be applied to different types of effects:

  • All pass filter = barberpole phaser.
  • Lowpass / high pass / notch filter = barberpole filter?
  • Short delay line = barberpole flanger.
  • Short delays & channel amplitude = pseudo-quad panning.
  • (Any effect) rate control = Risset-type increasing / decreasing tempo illusion.
  • Pitch = Shepard-Risset "scales".

You can hear some of the latter effects using the MicroPitch or H910/H949 algorithms.  The pitch shift is in the feedback loop, so regenerated tones constantly rise or fall.  It depends on whether there is a slight detuning above or below unison.  Not quite the same as Shepard tones, because there's no offsets or fading in & out of pitches.