Drum machine · qwen3.6-27b
Build a 16-step drum machine with a clickable grid for kick, snare, hi-hat, and clap, all sounds synthesized with the Web Audio API, plus play/stop and an adjustable BPM.
transcript · 8 messages
Build a 16-step drum machine with a clickable grid for kick, snare, hi-hat, and clap, all sounds synthesized with the Web Audio API, plus play/stop and an adjustable BPM.
thinking
The user wants a single-page drum machine web app with: - 16-step sequencer grid - 4 instruments: kick, snare, hi-hat, clap - All sounds synthesized with Web Audio API (no samples) - Clickable grid to toggle steps - Play/stop button - Adjustable BPM - All in one index.html file with inline CSS and JS - No external resources Let me build this with a clean, modern design. I'll synthesize each drum sound using Web Audio API oscillators and noise generators.
/workspace/index.html (19053 bytes)Successfully wrote 19053 bytes to /workspace/index.html
thinking
The initial version has a messy scheduler implementation. Let me clean it up - the `advanceTime` function is defined twice which is confusing, and the swing logic is a bit convoluted. Let me rewrite this with a clean, proper scheduler.
Let me clean up the scheduler logic — there's duplicate code and the swing implementation needs to be more robust:
/workspace/index.html (15445 bytes)Successfully wrote 15445 bytes to /workspace/index.html
thinking
Let me verify the file is valid and present.
{"command":"wc -l /workspace/index.html && head -3 /workspace/index.html && echo \"---\" && tail -3 /workspace/index.html"}512 /workspace/index.html <!DOCTYPE html> <html lang="en"> <head> --- </script> </body> </html>
thinking
The file looks good. Let me verify there are no syntax issues by checking the HTML structure more carefully.
The drum machine is ready at `/workspace/index.html`. Here's what it includes: **Grid:** 16-step sequencer for 4 instruments — Kick, Snare, Hi-Hat, and Clap. Click any cell to toggle it on/off. A white border highlights the currently playing step. **Synthesized Sounds (Web Audio API, zero samples):** - **Kick** — dual sine oscillators with pitch envelope (160→30 Hz + sub at 80→25 Hz) - **Snare** — triangle oscillator tone + high-pass filtered white noise burst - **Hi-Hat** — short band-passed (10 kHz) noise impulse - **Clap** — three closely-spaced noise bursts through a ~2.6 kHz bandpass filter with a sustained tail **Controls:** - **Play / Stop** button (also toggled with Space bar) - **BPM slider** (60–200, default 120) - **Swing slider** (0–100%) — shifts odd-numbered sixteenths forward for a groovier feel - **Clear All** button to reset the pattern **Preset pattern** loads on start: four-on-the-floor kick, backbeat snare/clap, and alternating hi-hats.
TAKE IT TO CODE
A single self-contained HTML file — copy it and open in any browser, or reuse the prompt with your own pi-agent run.
RUN
EVALUATION
16-step drum machine grid with kick/snare/hihat/clap, play/stop toggles, BPM slider, step playback highlight visible.
Vision grade · anthropic/claude-sonnet-5
MEASUREMENTS
Raw readings from the capture, not a verdict — the grade above is the only judgement. Percentages are how much of the screen changed; the measure under-reports sparse motion on a dark background.