# Audio Lab — Dub Techno Tape Desk

## Workstation brief

A browser-native dub-techno step sequencer built around the metaphor of a vintage tape deck.
Four tracks: **Kick**, **Snare**, **Hi-hat**, and **Echo** (a delay-sculpted feedback voice).
16-step grid. Tempo-synced tape flutter on the echo. VU meters on each track.
Pattern memory (save/recall up to 8 slots) via localStorage.

## Instrument set

| Track | Engine | Character |
|---|---|---|
| Kick | Sub-bass oscillator + short envelope | Deep, rounded, DB-01 style |
| Snare | Noise burst + body oscillator | Gritty, short, 808-adjacent |
| Hi-hat | Band-passed noise, short decay | Metallic, closed/pedal feel |
| Echo | Delay of kick track with flutter | Dub-style smear and diffusion |

All voices synthesized via Web Audio API — no samples, no external assets.

## Transport model

- Play / Stop / Record (arm for live step entry)
- Tempo: 60–160 BPM, rotary knob
- Swing: 0–75%, affects even steps
- Tape flutter depth knob (modulates delay time slightly per step)
- Master volume + mute all

## Visual direction

Dark nocturnal palette. Reel animation on play. VU meters per track.
Step indicators light up as the playhead sweeps. Active steps glow amber.
Delay trail indicator on the Echo track. Minimalist dark grey chassis,
cream/off-white labelling, amber LEDs.

## Interaction design

- Large tap-friendly step pads (min 44px touch target)
- Rotary knobs with drag-to-spin (horizontal drag = full sweep)
- Pattern slot buttons at the top — click to recall, long-press to save
- Mobile: one-column stacked layout, all controls reachable with one hand
- Audio context unlocked on first user gesture (start button)

## Persistence

Pattern data saved to `localStorage` as JSON.
Includes: step states per track, tempo, swing, flutter depth, master volume.