# V2 Racing Audio Deep

Section 115 defines racing-specific engine, exhaust, tire, brake, spatial,
ambience, music, and replay audio coverage.

## Engine Audio

The racing engine bank is per-vehicle and covers idle, cruise, mid-RPM,
high-RPM, redline, shift-cut, throttle-blip, decel-pop, and backfire bins. It
also covers V8 muscle rumble, inline-4 turbocharger, inline-6 NA, V12 supercar
wail, rotary RX-7 buzz, V-twin cruiser, Boxer rumble, and electric whir plus
induction hum. RPM and throttle parameters drive
`MetaSound.Racing.EngineRPMBins` through `AudioMod.Racing.EngineRPM` so the
RPM-modulated MetaSounds graph selects the correct sound bins.

## Exhaust

The exhaust catalog authors stock, sport, racing, open-pipe, titanium, and
carbon upgrade profiles. Each upgrade has its own sound profile table entry for
gain, resonance, and tail behavior.

## Tire And Brake

Surface tire noise covers asphalt squeal, dirt slide, mud splatter, sand whoosh,
snow crunch, and water hydroplane states. Heavy braking triggers brake-disc
squeal, with street, sport, and racing pad-type variation driven by brake
pressure.

## Spatial Routing

Doppler-shifted passing vehicle audio cross-references Section 43.5 spatial
audio and uses vehicle velocity for Doppler evaluation. 3D positional audio is
enabled for vehicles, cops, pickups, and Power-Play events.

## Ambience

Per-track ambience covers city traffic, highway wind, forest, desert, canyon
echo, industrial, coastal surf, and futuristic reactor hum. Weather-aware
ambience reacts to rain, thunder, snow, and wind, with canyon echo routed
through Audio Gameplay Volumes.

## Racing Music

Racing music cross-references Section 43 and covers Most Wanted heavy rock plus
dubstep, Blur EDM, Death Race industrial metal, GRID cinematic orchestral,
Carbon hip-hop plus electronica, NFSU2 dance plus drum-n-bass, Hot Pursuit
cinematic chase, and Pod Racer epic orchestral styles. The launch catalog has 60
tracks. Section 43.3 dynamic music uses ambient, chase, climax, and finish-line
stinger states with per-race state crossfade. Section 43.4 custom soundtrack
import follows per-platform music import rules.

## Replay Encoding

Replay audio cross-references Section 62.1. Each vehicle captures engine, tire,
brake, and music state for authentic playback, with a 32768 byte per-vehicle
per-minute state budget.

## Verification

`RacingAudioDeep_V2_Contract.json`, `racing-audio-deep.json`,
`RacingAudioDeep.spec.cpp`, `Audio.Module` automation coverage, config/subsystem
snapshot registration, CI registration, and `check-v2-racing-audio-deep.py`
validate Section 115.