That footswitch will have to take a beating [MTBF?]. You can do it in the PitchFactor using two aux switches (which are easily replaceable). {Note that it's also quite possible to assign KB0 – Mix and KB1 – Pitch Mix to a single Aux switch – see below}.
Use the HarModulator or H910/H949 algorithms to set up your intervals (e.g. 3rd and 5th). You could even use HarPeggiator, Crystals, or even PitchFlex with the right settings. Just intervals; no delays or extraneous parameters. Diatonic or Quadravox will get you scaled-constrained effects. Try that, "Impossible".
Under the AUX SW system settings:
KB0 (Mix) > TIP
MIN VAL – WET: 0
MAX VAL – WET: 100
KB1 (Pitch Mix) > RNG
MIN VAL – A10 + B0
MAX VAL – A0 + B10
One aux switch alternates dry signal and interval. The other aux switch alternates between the two pre-programmed intervals. Barely more fancy footwork than the Impossible Pedal, yet more controllable and configurable.
You can also do this with an external MIDI pedal. I use my FCB-1010 to alternate dry signal and intervals in a momentary (dry on release) configuration. Another way is to use the EHX 8 Step Program plugged into the PF expression pedal input.
It looks like this Impossible Pedal is similar to the Whammy DT momentary function, except feeding two pitch shifters. I read that it was based on Belew's Harmony Man technique. Cool enough, but I'll stick with my Whammy / Ring Thing / PitchFactor combination to cover my pitch mangling needs.
