That’s going to be a tricky one, BenG, for a number of reasons. HotSawz does have Gate Sustain, but you can modulate the levels for up to 6 seconds (Attack + Decay). It also has an envelope follower, but it’s going to ‘drop off’ when your input reaches a certain threshold.
Some algorithms (especially reverbs) allow you to freeze, but ‘indefinitely’ often depends on the structure, modulation, EQ … You can easily create pads using H90 reverbs, though.
The newer pitch algorithms dedicate a Performance Switch to FREEZE, but I honestly don’t know how that might hold up through a Preset change.
Just speculation, I don’t know if this would work. I’m thinking along the lines of 2 two-part Programs. Preset A being the part you change in both Programs, in series with Preset B being the same for both Programs.
Something would have to ‘excite’ Preset B through the Program change. As a start, I would try a reverb with an INF decay. It might ‘survive’ a Preset switch; it might not.
I built an ‘infinite sustain’ Program out of two reverbs, quite a while back. I’ll see how that reacts in the scenario you’re describing.
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