In this segment from a Bitwig Studio Grid walkthrough, the presenter works through the logic of building a looping AD envelope from scratch, using comparators, logic gates, and a feedback delay to make a standard envelope retrigger itself continuously while a note is held.
The core insight is that an AD envelope always returns to zero at the end of its cycle, and that zero point is the detection signal. A comparator catches it, an AND gate checks whether the note is still held via the gate input, and if both conditions are true, the envelope fires again.
The feedback half of the patch introduces a delay module to break the signal chain, which is what makes routing an output back to a trigger input possible without creating an infinite loop crash. A very short gate pulse is generated from the feedback path, then merged with the original gate signal using an OR gate, so either a new note or a completed cycle can retrigger the envelope.
The result is a looping envelope built entirely from reusable modular logic concepts, none of which are Grid-specific. The comparator-plus-logic-gate approach transfers to any modular environment where you need conditional triggering based on signal state.