Drum machine · qwen3.7-plus
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 · 4 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. Let me plan this out: 1. 16-step sequencer grid 2. 4 instruments: kick, snare, hi-hat, clap 3. All sounds synthesized with Web Audio API (no samples) 4. Play/stop button 5. Adjustable BPM 6. All in one self-contained index.html file Let me think about the Web Audio API synthesis for each sound: - **Kick**: Low frequency sine wave with pitch envelope (high to low) and quick decay - **Snare**: Mix of noise and triangle wave with bandpass filter, quick decay - **Hi-hat**: High-frequency noise, highpass filtered, very short decay - **Clap**: Multiple noise bursts with bandpass filter, medium decay For the grid: 4 rows × 16 columns of clickable cells. I'll highlight the current step during playback. Add a playhead indicator. Let me design this with a nice dark theme UI typical of drum machines. BPM control: a slider or number input, typical range 60-200. Let me write this out completely.
/workspace/index.html (22465 bytes)Successfully wrote 22465 bytes to /workspace/index.html
thinking
The file is written. Let me verify it's there and check its contents are reasonable.
Done! Open `index.html` in any browser — everything is self-contained. Here's what you get: --- ## 🥁 16-Step Drum Machine — Feature Breakdown ### 🎵 Sound Synthesis (Web Audio API, zero samples) | Sound | Technique | |-------|-----------| | **Kick** | 150 Hz sine osc with pitch sweep to 30 Hz + a square-wave transient click | | **Snare** | Layered: highpassed white noise (crack) + triangle osc detuning from 220→120 Hz | | **Hi-hat** | White noise through a highpass + bandpass pair, ultra-short 80 ms envelope | | **Clap** | 4 rapid noise bursts followed by an exponential-decay tail, bandpass filtered | ### 🎛️ Controls - **Play / Stop** button (also **Spacebar**) - **BPM slider** — 40–240 BPM - **Swing** — offsets odd 16th notes for groovier feel - **Per-channel volume** sliders - **Right-click** any pad to preview the sound - **Clear** button to wipe the grid ### 🎨 Interface - Dark gradient UI with color-coded rows (🔴 kick, 🟡 snare, 🟢 hi-hat, 🟣 clap) - Animated playhead that glows on the current step - Click any step to toggle — the sound fires immediately for confirmation - Built-in presets: **Rock · Hip-Hop · Techno · Breakbeat · Reggaeton** (auto-adjusts BPM)
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 play/stop, BPM, swing, volume sliders; click toggles a step and playhead animates during play.
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.