How it works — the clocks above each pulse at their own step-division. Each drum voice listens to two clocks, A and B, through a logic gate; the gate's output triggers the sound. Change a clock's division/offset or a track's gate and every voice downstream reshuffles in real time. Use the + tile to add a clock (up to 12) or the × on a module to remove one (down to 2) — anything pointing at a removed clock falls back to clock I automatically. New clocks start unmapped in MIDI; bind them from the MIDI MAP tab with Learn.
AND both must pulse · OR either pulses · XOR exactly one pulses (never both) · NAND/NOR/XNOR inverted versions of the above · A ignore B, just play clock A · NOT A play on every step A does not pulse.
LFO — turn the ∿ LFO button on, then tick the small LFO tag under any clock to let that clock's divide/offset drift slowly up and down over the period set above (each enabled clock drifts slightly out of phase with the others, so the whole rack breathes rather than jumping in unison). Drift continues even while stopped.
MIDI — click ♪ MIDI and allow access to control the rack from a hardware or software MIDI controller (Chrome/Edge, requires the page be served over https or localhost). Every CC number is reassignable in the MIDI MAP tab above — hit Learn and move a control on your device to bind it, or type a CC number directly. If clicking ♪ MIDI reports "access denied" or "blocked," it's almost always the page's environment, not your controller — an embedded preview frame generally isn't allowed to request hardware MIDI access at all. Save the file and open it directly in its own browser tab (double-click it, or open it from your downloads) and the permission prompt should appear normally.

MIDI Map — each row below is one parameter. Type a CC number (0–127) to bind it by hand, or press Learn and then move a knob/fader on your MIDI device — the next Control Change message received binds to that row automatically. Clear a row to stop it responding to MIDI. Rows sharing the same CC number are flagged — only the last-registered one will respond. Defaults are pre-wired to a stock Akai MIDImix: its 8 faders run the 7 track volumes plus master, and its knobs cover clock division/offset, tempo, swing, and the LFO — no editing needed if that's your controller. Its mute/rec-arm buttons send Notes rather than CC, though, so those aren't used here; everything is still reachable via a spare knob or the Learn button.

Patterns — save the whole current rack — clocks, gates, tempo, swing, LFO, everything — as a named block. Click a block to load it onto the Rack tab for editing (it swaps in live, on the next step, if something's already playing). Drag blocks onto the timeline to build a song; each slot's number is how many loops of that pattern play before the song advances to the next one.

Samples — upload your own WAV files here. A slot only shows up in a track's voice dropdown (back on the Rack tab) once it actually has audio in it — an empty slot is just something you're setting up. Rename a slot any time; the name updates everywhere it's already selected. Stored locally in this browser (audio in IndexedDB, names in local storage) — a sample uploaded here won't travel with a shared or downloaded copy of this file elsewhere unless uploaded there too.