In hindsight, I did a disservice to the expression pedal modulation source by glossing over its capabilities.  It could be considered an expansion port  into modulation control.  Most of us just plug in an expression pedal, and pump away.  But it could be any ~ 25K variable resistor, or 0-3 VDC source.  Photocell, joystick, modular synth module, step sequencer, computer-based DAW automation track …  That one feature opens up a window into modulation control that goes well beyond “Heel = low limit modulation.  Toe = high limit modulation”.

You could make the argument that anything digitized is a form of sample & hold.  I have a rack unit that really opened my eyes into the possibilities.  Any control source (CCs, audio, LFOs, envelope follower, ADSR, etc.) can be used as the S&H input, and any of those same control sources can be used as the Clock Generator.  So you can end up with Sample and Hold MIDI CC outputs like this:

The output of Eventide’s Sample & Hold is ‘hardwired’ to a Random waveform as an input source.  But by using the “expansion port” (expression pedal input jack), we can gain control over all of the algorithm parameters.  And we can ‘morph’ through any or all of those parameters with a number of ‘modulation sources’.  Direction and value limits are highly configurable within the H9 itself.

st.bede, we’ve discussed using sequencers and advanced expression pedals here on the forum.  All of that can be considered an extension of Sample & Hold modulation.  Lately, I’ve been focused on using the Reflex pedal and 8 Step Program sequencer over parameters that aren’t directly accessible to the standard modulation shapes.  External control over delay time alone is a fascinating area for deep exploration.  It’s not much different than creating your own algorithms.