This is just a little brainstorming because I think after being obsessed with the Dynaflanger my next obsession is a nice feedback emulation:
You need a sinus wave to emulate feedback. I think not Hot Sawzs, but Synthonizer on the H90 can generate a sinus wave.
Normally you got the sinus generator first in chain and then you apply distortion to it.
Just as a side not in my signal chain the H90 is the last device before the signal goes to my Audio Interface, but maybe this is not a complete show stopper. Or if you see it in a positive way if the signal is already distorted and you can combine only two effects on the H90 you don’t need to use the second effect for distortion, but rather for delay or something which makes sure that the effect really fades in slowly. Well, you know what I mean. Something like if you were using a volume pedal or an Auto Swell Effect or however you want to call it.
Could this maybe be done with the Blackhole or another Delay Effect on the H90? If yes, what would be the basic settings? The Synthonizer seems to be able to produce also the octave above the tone which in my opinion is the most fail save feedback tone because it is always diatonic. At the same time Feedback is almost every time associated with a certain degree of dissonance caused by the following harmonics. So it would be nice if it would be possible to fad in the fifth harmonic towards the end of the feedback effect, but I don’t know if this is possible with the Synthonizer or if there is another workaround to avoid that the Feedback gets to clean.
The big exception is Flying in a blue dream where you really want a very diatonic feedback with almost no dissonance at all, but normally as I said you want a little bit more dirt – you know what I mean. I don’t know if you have ever heard of the Mojo Roller Effect on the Zoom Multistomp. I don’t have this device, but the other day I stumbled upon a description of this effect. In simple terms it means that a tone gets in his decay phase a certain amount of vibrato. I think it would be great if the Synthonizer would be able to emulate this to a certain degree, but if you look on the parameter list above it seems that there is no vibrato parameter…
So what do you think? Have I described correctly the necessary elements in order to make the ultimate feedback emulation on the H90? I have to admit that I have only a very superficial understanding of those things, but sometimes you have to take the challenge right?

Synthonizer¶
Synthonizer tracks the pitch of the note that you’re playing and generates a synthesized tone at the same pitch. Voice A is an additive synthesizer useful for creating organ or Theremin-style sounds; Voice B is a subtractive synthesizer for creating classic analog-style synth sounds.

Mix: Wet/dry mixer, 100% is all wet signal.
Vox Mix: Controls the ratio of the two synthesized voices A and B.
Wave Mix A: Controls the mix of the various added waveforms to control the tone and perceived pitch of voice A.
Octave B: Controls the blend between unison, 1 octave down, and 1 octave up synth voices to control the tone and perceived pitch of voice B.
Attack A: Controls the attack time for synthesized voice A.
Attack B: Controls the attack time for the filter on synthesized voice B.
Verb Level: Sets the reverb level.
Verb Decay: Sets the reverb decay time.
Shape A: Selects voice A waveshape:

Sine
Triangle
Sawtooth
Organ 1
Organ 2
Sweep B: Controls the sweepable filter on voice B. Values from 0 to 50 sweep a low-pass filter, values from 50 to 100 sweep a high-pass filter.
Performance Parameters
Flex: Shifts both voices up one octave.
Factory Presets
Bassic Synth
FluteFactor
Motorbike Lead
TromboneFactor
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