Chapter 3
Envelopes
Attack, decay, sustain, release — the shape of a note over time.
After this chapter: “I can shape a note over time.”
3.1
Four stages, one gesture
An envelope draws a shape every time you press a key. Attack is how long it takes to rise to full. Decay is how long it takes to fall to the sustain level, which holds as long as the key is down. Release is how long it fades after you let go.
Sustain is a level, not a time — that trips up nearly everyone at first.
3.2
Point it at anything
Sent to the amplifier, an envelope controls loudness: short attack and decay with zero sustain makes a pluck; a long attack and release makes a pad. Sent to the filter cutoff, the same shape makes the tone open and close — that is the "wow" in a classic synth bass.
Drum voices are envelopes too: a kick is a sine whose pitch envelope drops fast while its amp envelope decays.
On real gear · Hydrasynth Deluxe
Five envelopes per voice. Envelope 1 is pre-wired to the filter and Envelope 2 to the amp, but any of them can be assigned anywhere through the mod matrix.
Experiment #3-1
Pluck, then pad
Turn one sound into two instruments with four controls.
- 1.In the figure, set SUSTAIN to 0% and DECAY short. That shape is a pluck.
- 2.Set ATTACK and RELEASE long, SUSTAIN high. That shape is a pad.
- 3.Rebuild both shapes on the VCA · ENV band in the Signal Path Explorer.
You should hear…
A pluck dies on its own even while you hold the key. A pad swells in and keeps ringing after you let go.
Doesn’t sound right?
Notes stop instantly? R is near zero, or the ENV is on BYPASS.
- Hydrasynth Deluxe
- SH-01A
- TR-8S
More recipes from this chapter
Full interactive panels with the same Manual & Panel layout — steps stay readable as text.
Check yourselfYour pad keeps playing after you release the key. Which stage is long?Reveal
Release — it controls the fade after the key goes up.
Next on the path
Stamp the recipes above, then either keep reading or step onto the gear route when you want a specific instrument’s panel language.