The AHDSR Envelope controls operate the same way for all the different envelope types in Trilian.

The screenshot above is from the Envelopes Zoom page, but illustrates what a standard AHDSR Envelope looks like. The first to second point (or Stage) is the Attack time. The second to third point is the Hold time. The third point is the Decay time, which ends at the fourth point, the Sustain level. After the note is released, the Sustain level drops away at a rate based on the Release time.

When viewed on the MAIN page, the AHDSR Controls looks like this:

A – Attack

The ‘A’ stands for ATTACK, which means the attack time of the envelope. At minimum setting, the Attack is immediate, so the Envelope will start as soon as a controller triggers it. Higher settings will delay the Attack time, so the sound will gradually fade in.
Range between 0 to 20 seconds

D – Decay

The ‘D’ is the DECAY time, which begins after the Attack has reached its maximum level. At minimum settings, the Decay will be zero, which means there is no Decay after the Attack and the Envelope goes straight to the Sustain stage. At the maximum setting, the DECAY can be about twenty seconds before the Sustain stage starts.
Range between 0 to 20 seconds

S – Sustain

‘S’ is the Sustain Level. Unlike A, D, and R, Sustain is not a time value; it’s a level value. Sustain determines at what level the Envelope’s output remains constant while a note is held. At the minimum setting there is no sustain, so the envelope’s output will stop until it’s been retriggered. Higher sustain settings mean the Envelope’s output will be constant as long as a note is held down.

R – Release

‘R’ is the Release time value. After a note has been let go, the sound will continue to decay for the duration of the Release time. Raising this fader lengthens the Release time. Lowering it decreases Release time.
Range 0 to 20 seconds


The HOLD knob opens the envelope at maximum amount for a certain period of time before allowing the Decay to begin. Turning the knob clockwise increases the length of the Hold. Turning the knob counter-clockwise decreases the Hold time.
Range between 0 to 20 seconds

VELO (Envelope Velocity)

VELO is short for Velocity Sensitivity and is available for the AMP and FILTER envelopes. The Velocity knob controls how much MIDI velocity will affect the output signal of the Envelope. Moving the knob clockwise increases the dynamic sensitivity of the envelope, and moving it counter-clockwise decreases the sensitivity. This control is duplicated as a fader in the AMP and FILTER tabs in the Filter Zoom.

NOTE: Each of the VELO controls for the four AMP and four FILTER envelopes are independent. The VELO control will affect only the selected envelope.


The DEPTH controls are dedicated to the two MOD Envelopes and are only visible when either of those 2 tabs are selected. Turning this knob clockwise increases the envelope’s dynamic output that is sent to the Modulation Matrix. The default setting is at maximum.

NOTE: The DEPTH controls for the Modulation Envelopes are independent. The DEPTH control will affect only the selected envelope.

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