Yes. Without getting into the history of the Sustain pedal, and how it was designed to work (and on which instrument)... we'll pick up the story with electronic synthesizers and how they attempt to recreate this musical gesture.

The Sustain function interacts with the Amplitude Envelope Generator (AEG). The AEGs job is to describe the loudness shape of the signal from start to finish. Start being Key-On and finish is described by what happens at Key-Off and just beyond. We all know how it works in an acoustic piano... in the synth Sustain is cc64 technically called "HOLD 1" - it is the same as holding down a key. The Sustain pedal on electronic devices takes the place of holding down the key.

What happens while the Key is held (as concerns output level) can be described by the AEG.

Early analog synths had ADSR (Attack, Decay, Sustain, Release). Digital synths introduced more complex AEGs - not only in the number of segments, but in the sheer number of AEGs available per sound, and also how and where they existed - each Oscillator in an FM synth includes an AEG. In the AWM2 engine each Element has its own... the AEG here is described by a set of TIME and LEVEL parameters.

In the AWM2 AEG the "Decay 2 Level" parameter describes the Sustain Level. Sustain Level is literally the output level of the signal while the Key is still being held down. If "Decay 2 Level" is anything but zero you will hear the sound indefinitely. If "Decay 2 Level" is 0 the sound will eventually die out completely in spite of the Key being held. How long it takes to reach this segment is determined by the various TIME segments.

So all percussive family instruments (of which piano is one) will have Decay 2 Level = 0

String sounds in synths that are mimicking bowed strings will have Decay 2 Level at a significant value... this way you can continue "bowing" indefinitely just like a string player. There is no fade to zero as found in a percussive instrument sound (unless you pluck the string - a plucked string would have Decay 2 Level = 0)

Rule: Hammered, struck or plucked envelopes Decay 2 Level = 0
Rule Self-oscillating instruments can hold notes indefinitely... bowing or blowing can be indefinite so Decay 2 Level is a significant value.

When you let go of the Key or Sustain pedal, this is considered Key-Off, the RELEASE segment describes how the sound eventually disappears - is it slowly disappearing or rapidly disappearing...

Also an important thing to recognize that the envelope is a journey, if you release the Key quickly, as in a staccato gesture, the envelope may not have time to do its full journey, it will jump directly to the RELEASE segment.

The Montage features additional Sustain pedal functions that mimic an acoustic pianos ability to half damper (requires FC3A).

Envelopes can be very important in getting a sound to behave as you require and it can (and does) vary on a per program basis. To quickly OFFSET the Release setting, you have a dedicated RELEASE Knob in the Knob Control area. Values clockwise from 12 o'clock position create a longer Release...

Thx for the info-
Got it 🙂