Drum machine · glm-4.7
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 · 3 messages
thinking
The user wants a single-page web app that is a 16-step drum machine. Let me plan this out: 1. **Features needed:** - 16-step sequencer grid - 4 instruments: kick, snare, hi-hat, clap - Clickable grid cells to toggle beats - Play/Stop controls - Adjustable BPM - All sounds synthesized with Web Audio API (no external audio files) 2. **UI Structure:** - Header with title - Controls section: Play/Stop button, BPM slider/input - Grid: 4 rows (instruments) x 16 columns (steps) - Visual feedback for current step 3. **Web Audio API synthesis:** - **Kick**: Low frequency oscillator with rapid pitch drop, short envelope - **Snare**: Noise burst + oscillator component, short decay - **Hi-hat**: High-pass filtered noise, very short decay - **Clap**: Multiple short noise bursts with envelope 4. **Sequencer logic:** - Current step tracking (0-15) - Timing based on BPM (16th notes) - Scheduler using Web Audio API's timing or setInterval/setTimeout - Visual indication of current playing step 5. **Styling:** - Dark theme for music app feel - Grid layout for the step sequencer - Active/inactive states for cells - Current step highlight Let me build this complete app in one index.html file.
I'll create a 16-step drum machine with synthesized sounds and all the features you requested.
/workspace/index.html (20149 bytes)Successfully wrote 20149 bytes to /workspace/index.html
thinking
I've created a complete 16-step drum machine in a single index.html file. Let me verify it was created correctly.
I've created a complete 16-step drum machine in `index.html`. Here's what's included: **Features:** - **16-step grid** for 4 instruments (Kick, Snare, Hi-Hat, Clap) - **Clickable cells** - click to toggle beats on/off with color-coded instruments - **Play/Stop button** - toggles playback with visual feedback - **BPM control** - slider (60-200) and number input synced together - **Current step indicator** - highlights the playing column and shows step number - **Clear All button** - resets the entire pattern - **Keyboard shortcut** - Spacebar to play/stop **Synthesized Sounds (Web Audio API):** - **Kick** - Low oscillator with rapid pitch drop (150Hz → 0.01Hz) - **Snare** - Layered noise burst + triangle oscillator tone - **Hi-Hat** - High-pass filtered white noise (7kHz cutoff) - **Clap** - Multiple short noise bursts for authentic clap sound **Visual Design:** - Dark gradient theme with neon accents - Color-coded tracks (pink kick, green snare, yellow hi-hat, blue clap) - Glowing effects on active and current steps - Beat markers on every 4th step - Responsive layout for smaller screens The app loads with a default pattern so you can hear it immediately, and clicking any cell previews the sound!
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/hi-hat/clap, play/stop via Space toggles playback and BPM control works.
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.