The Envelope

ADSR

• Attack — how long the note takes to reach full level. Fast for percussive and plucked sounds, slow for pads that swell in.
• Decay — how long it takes to fall from the attack peak down to the sustain level.
• Sustain — the level the note holds at while you keep the key down.
• Release — how long the sound takes to fade after you let go.

Fade

Fade is the control that turns a synth that holds forever into one that decays like a real instrument. At 0, a held note sustains indefinitely — organ and pad behavior. Turn it up and a held note keeps fading toward silence even while you’re holding the key, the way a piano or mallet note dies away. It’s the single knob that separates “sustained” instruments from “struck” ones.

VCA and VCF — the amounts

These two decide how much the envelope actually does:

• VCA — how much the envelope shapes the volume while the note is held. At 0 the level is flat (organ-style — on while held, off when released); at 100 the full envelope shapes the loudness. Either way, the release always fades to zero when you let go.
• VCF — how much the envelope opens the filter. Turn it up and every note gets a filter sweep that follows the envelope shape — bright on the attack, settling as it decays. This is how you get the classic envelope-into-filter “wow” without touching the mod matrix.

A second envelope

There’s also a second envelope, Env 2, living over in the Modulation section, with its own ADSR and its own VCA/VCF contribution amounts — for when you want one envelope on the amp and another driving something else entirely. That’s covered in the modulation chapter.

What to Practice

• Build a pad: slow Attack, full Sustain, Fade at 0 so it holds.
• Now make it a mallet: fast Attack, Fade up so a held note decays on its own.
• Turn VCF up on a bright patch and play — hear the filter sweep on every note, shaped by the envelope.