VX Drum Machine

A six-voice drum machine in one panel: kick, snare, clap, rimshot, and a pair of hi-hats, with a 16-step pattern grid, an accent lane, and sixteen pattern memories. Every sound is synthesized — analog-style circuits, no samples — so the knobs reshape the drums themselves, not a recording of them.

How it works

The top row is the kit: seven columns of four knobs, one per voice plus a master strip, and the bottom knob of every column is that voice's level — read it as a mixer. The knobs are global: patterns change with the memory buttons, the kit stays put, exactly like the hardware this is modelled on.

The grid below is the pattern: six voice lanes plus AC, the accent lane. Click pads to place hits, drag to paint. A step in the accent lane makes every drum on that step hit harder — and because accent drives each voice's own circuit harder, accents come out brighter too, not just louder. The closed hat chokes the open hat, the classic trick for playing a hi-hat line on one pair of circuits.

Controls

  • BD — TUNE sets the fundamental (30–100 Hz), DECAY the ring

(0.05–1.5 s), PUNCH the pitch-sweep attack. The 808 mechanism: a struck resonator, no oscillator.

  • SD — TUNE moves the two shell modes, DECAY the noise tail, SNAP

the noise-to-shell balance. A 909-style snare.

  • CP — TONE sets the clap's band, DECAY the room tail, SPREAD the

spacing of the three quick bursts that make a clap read as hands.

  • RS — TUNE (300–1200 Hz) runs it from woody rimshot up to clave,

DECAY is very short by design, DRIVE adds bark.

  • CH / OH — TONE brightens, DECAY sets the ring (the open hat goes to

1.2 s), METAL moves each between pure metallic ring and pure sizzle.

  • MASTER — ACCENT is how much harder accented steps hit; SWING delays

the offbeat sixteenths for shuffle; DRIVE is one knob of saturation on the stereo mix; VOLUME is the output.

  • Clock — where the tempo comes from. Ext steps once per pulse at the

CLK input. Int runs at its own BPM with the ▶/⏹ transport. Song follows the timeline: one step per sixteenth, and the pattern is a pure function of song position — drop the playhead anywhere and the right step plays. Swing works in Int and Song; in Ext the cable owns the timing.

  • Random — writes a new beat into the current memory with sensible

roles per lane (kick on the floor, hats busy, accents on the push). One undo step.

  • Lamp row — the playhead chases here; click a lamp to set this memory's

pattern length (1–16).

  • Lane labels — click to mute a lane; the accent lane mutes too.
  • Ratchets — right-click any lit pad and pick ×2, ×3 or ×4: the step

subdivides into that many evenly-spaced hits, and the pad splits into slivers so you can read the roll at a glance. Works in every clock mode — in Ext the machine measures the incoming clock's period to know how long a step is, so the first pulse after connecting plays single hits and everything after subdivides correctly.

Memory

Sixteen patterns live in the row of numbered buttons. Each memory is its grid and its length. Right-click a button for Copy / Paste / Clear — and paste works across VX Drums instances. Patch a CV into MEM (0–10 V → memory 1–16) and the CV owns which memory plays; the buttons lock and the red LED chases the live slot. Sequencing the MEM input is how you chain patterns into a song.

Inputs & outputs

  • CLK — external clock, one pulse per step (Ext mode).
  • RST — a rising edge restarts the pattern (in Song mode it rewinds the

song, since the position is derived from the timeline).

  • MEM — memory-select CV, 0–10 V across the sixteen slots.
  • OUT L / OUT R — the stereo mix: voices sit at subtle fixed pans, through

the master drive and volume.

  • BD / SD / CP / RS / CH / OH — individual outs, one per voice, dry: level

and accent applied, drive and volume not. Take a voice out to its own processing and it disappears from nothing — the mix still carries it, so turn its level down there if you want it fully separate.

Tips

  • Start with Random, then edit — deleting the wrong hits from a real beat

is faster than placing the right ones on silence. It seasons lightly with ratchets too.

  • A ×2 on the last closed-hat of the bar is the cheapest fill there is; a

×3 snare on step 15 announces the next section.

  • SWING at around a third of its range is the classic MPC feel; all the way

up is a hard shuffle.

  • An accent every 3 steps against a 4-step kick (accents on 1, 4, 7, 10, 13,

16) is the cheapest polyrhythm in the book.

  • Short OH DECAY plus METAL high reads as a ride; long and noisy reads as

a crash wash.

  • Memories are patterns, not kits — sound-design lives in the knobs and stays

put across all sixteen, so a MEM CV sequence plays arrangement, not presets.