Maths Signal IN accepts a gate to generate an ASR envelope whose sustain level tracks the gate voltage

Patching a gate to Maths Channel 1 or 4 Signal IN (not Trigger IN) creates an Attack/Sustain/Release envelope: the function rises to the gate’s own voltage at the RISE rate, sustains at that level while the gate is held high, then falls at the FALL rate when the gate ends. This contrasts with the Trigger IN path which always rises to 10V. The sustain level is therefore determined by gate voltage — allowing dynamic expression by varying it.

Examples

Patch a gate (e.g., from a sequencer) to CH.1 Signal IN (not Trig IN). Adjust RISE and FALL. Use a velocity-sensitive gate to vary sustain level. Take output from CH.1 Signal OUT.

Assessment

What is the difference between patching a gate to Maths Trigger IN vs. Signal IN, and why does gate voltage matter in the Signal IN case?