# Original soundtrack and effects

All usable audio is included under `QuietPlaces/Resources/Audio` as 44.1 kHz, 16-bit stereo PCM WAV. There are **25 assets**: five music files, five current notes, twelve destination cues and three equipment/prestige cues. No third-party recordings, loops or samples are used.

`Tools/compose_soundtrack.py` contains the original musical event score and deterministic additive synthesis. It renders soft piano-like tones, delicate plucked notes and sustained warm textures. It is reproducible using Python and NumPy. This score was composed specifically for A Map of Quiet Places; it does not reuse the previous games' music.

## The music

- **A Line on the Water** — 96-second title theme. A descending fifth and an open second move through eight slow bars.
- **The current beneath** — 180-second common voyage foundation, twelve slow bars of open C, A-minor, F and suspended G voicings.
- **The Nearwater** — a spare piano question with plucked replies.
- **The Pale Expanse** — higher voicings and more space between gestures.
- **Beyond the Fold** — a lower returning motif with a sustained response.

All four voyage stems have exactly equal lengths. Events and reverberation tails wrap around their loop boundaries. During gameplay the foundation and only the current region's part are audible; all stems share the device sample clock. Two-second volume fades transition between the title, voyage and regional layers. This keeps the arrangement sparse.

The five current notes share the score's pentatonic vocabulary. Inputs are limited to one every 0.8 seconds; the effects engine holds at most three simultaneous voices. Each of twelve places has a distinct, restrained three-note arrival signature. New Bearings and Passing the Atlas have different soft cues. None is a repeated notification sound.

## Delivery and measurements

`Release/Audio` includes AAC listening previews of the title and three complete regional arrangements. `AUDIO_MANIFEST.json` records each playable WAV's length, peak, RMS, loop seam delta and SHA-256. `Release/Audio/mix-checks.json` measures complete regional mixes.

The complete arrangements peak below 0.136 full scale before the player's volume setting; no clipping was found. Their adjacent sample differences at the loop seam are at or below 0.00104. Sampled spectral checks show very little energy above 8 kHz. These are signal measurements, not a substitute for listening on real headphones and iPhone speakers.

## Runtime behaviour and actual tests

Music and effects levels persist separately. The ambient audio session respects the silent switch and mixes with the player's audio. Backgrounding pauses music and stops effects. Interruptions pause playback; ended interruptions resume only with the system's resume option. A disconnected output route pauses sound until a preference adjustment or a new foreground session. Muting music fades down before pausing.

The app-host test loads every asset through AVAudioPlayer, verifies stereo channels and equal 180-second voyage lengths, checks synchronised layer positions within 40 ms, and exercises foreground/background, interruption/no-resume/resume and saved zero volume. All passed in the simulator. Real-device speakers, headphones, route transitions and subjective listening remain hardware checks; they are not claimed complete.