User`s manual

3.3 Tweak the envelope
Now let’s shape the sound’s amplification envelope, which determines how the
level changes over time when you play a note. Until now the Sustain level has
been set to maximum, which results in an “electronic organ” sound that has no
dynamics. By changing the other parameters (Attack, Decay, Release) we can
control how the sound fades in, sustains, and fades out.
Increase the AMPLIFICATION ENVELOPE section’s Attack slider to its middle position,
then press a key. Now the sound rises slowly up to the sustain level. As soon as you
release the key, the sound stops abruptly. Raise the Release slider, and the sound
will fade out to its minimum level when you release a key.
Here’s an overview of the patch:
Arturia MiniBrute SE User's Manual 16 3 Quickstart