Drum programming is the art of placing kicks, snares, and hats in time to create the groove that every other instrument sits on. Here's what the controls do and how to build a pattern that actually moves.
A 16-step grid represents one bar of 4/4 time divided into 16 equal slices (sixteenth notes). The kick usually sits on steps 1, 5, 9, 13 (the downbeats). The snare lives on 5 and 13 (the backbeats, beats 2 and 4). Hi-hats pepper every step or every other step. That simple template — kick on 1 & 3, snare on 2 & 4, hats everywhere — is the foundation of 90% of popular music.
Perfectly straight 16ths sound mechanical. Real drummers and hand percussionists play the off-beats slightly late — pushing the "and" of each beat a few milliseconds back. Swing percentage controls this: 0% is mechanical, 50% is a classic shuffle (dotted-eighth feel), 65-75% is heavy swing (hip-hop, neo-soul, J Dilla). Dial in swing and a static pattern starts to breathe.
Every hit having identical volume is the giveaway that a pattern is programmed, not played. Velocity lets you make some hits louder, some softer. Ghost notes (quiet snare hits between the main backbeats) are the secret to any funk or trap pattern feeling alive. Click a cell to toggle it, click again to set it "hard" or "soft."
The voice mixer lets you isolate a single drum voice (solo) to hear it in context, temporarily mute a voice, or pan it left/right in the stereo field. Panning hi-hats slightly right and ride cymbals slightly left (or vice versa) gives the kit more spatial width — even though they're synth voices, they'll feel like a real kit.
The drum sounds in this tool aren't samples — they're generated on the fly from oscillators and noise. The kick is a sine wave with a fast pitch sweep from 120Hz down to 30Hz, plus a brief click transient. The snare is white noise through a bandpass filter around 1kHz, layered with a short sine "body." The hi-hat is white noise through a highpass filter with a short decay. This approach means zero download size and every kick, snare, and hat is unique and parameterizable.
Save patterns to your browser for later. Export to JSON to email or version-control your beats. Hit Record to bounce the performance to a WAV file you can drop into any DAW.