The Micro has the same synthesis engine as the newer Meeblip SE, which has dual A(S)R envelopes – one for the filter and one for amplitude. It’s a more versatile configuration than the original (allows filter sweeps, etc) while only requiring 4 knobs.
Internally, the envelopes are actually ADSR and we’ll make each parameter accessible individually by MIDI in a future update.
FYI —
When the Envelope Sustain switch is on, the sustain level is set to 100%, the decay time is set to 100%, and the decay knobs controls envelope release – great for LFO drones.
When the Envelope Sustain switch is off, the sustain level is set to zero and the decay knobs control both decay and release.