Stepper

Stepper is the first GENERATOR in this family. Arpeggiator and Steps rearrange notes you are holding - let go and they stop. Stepper writes its own line: 32 steps, each carrying a pitch, a velocity, a gate length, a tie flag, a curve value and a ratchet count, played back on its own tempo clock whether or not a single key is down.

The model is Propellerhead Reason's Matrix Pattern Sequencer, taken deliberately rather than loosely. Matrix's shape is here in full - 32 steps, the Note, Gate and Curve lanes plus per-step Tie, 32 patterns arranged as four banks A-D of eight, a per-pattern length from 1 to 32, a Resolution divisor and a 1-5 octave range. Two things are borrowed from Redrum next door: pattern chaining across a bank range, and the flam, which arrives here as a per-step ratchet of one to eight retriggers. Key follow is RPG-8's - a held note transposes the whole pattern relative to C3 - and the scale-quantize lane is new, so a written line can be pushed into a key without editing every step.

Matrix emits CV. This repo's ports are MIDI, so the translation is explicit: the Note and Gate lanes become note-on/note-off pairs, and the Curve lane becomes a configurable CC, sent only when its value actually changes so a flat lane costs nothing on the wire.

Pattern data is not parameters, and that is a design decision rather than an omission. Four banks of eight patterns of 32 steps across seven lanes is far more than an automatable schema should carry, and Reason does not automate pattern data either - it is part of the patch. So the twenty-one globals (tempo, resolution, shuffle, gate and velocity scaling, transpose, octave, direction, pattern, length, chain, curve CC, key and scale, seed, channel) are ordinary stepper.* params that ride presets, share links and MIDI learn, while the seven step lanes live in the pattern and are edited in the grid. Two of them cross the line and are mirrored as parameters of the SELECTED pattern: its loop length, and its 32 velocities as stepper.g1 to stepper.g32 - so a host with no custom UI still has a groove it can hold, and switching pattern re-points both.

This page is a preview. The scheduling is real - every note is committed to the AudioContext clock as an absolute time, so timer jitter delays the decision and never moves the note - but the sequencer behind it is the website's reference implementation, not the compiled kernel, and no parity claim applies to it. The compiled stepper-sequencer kernel is a separate, ABI-pinned artifact; when it is wired to this page the module's behaviour becomes a matter of goldens rather than of this file.