Behavioural specifications behind the native audio port (doc 11) and the world audio hook-in (doc 15). Code comments in crates/skate-audio and crates/skate-game/src/game_audio cite them as audio-specs/<name>.md §n; the section numbers are kept stable for that reason.

What these are

Written in our own words from reading the Skate 3 TU 3.0.3.0 recompilation, the disc data and the attribute database, then checked against traces of the running recompilation. Function addresses (sub_8xxxxxxx), object offsets and image constants are given as references so a reader can find the same code; no game code or game data is copied here.
Measured values (levels, rates, timings, counts) come from the recompilation unless a line says otherwise. The recompilation is not the console: its frame rate, timing and threading differ, so its program logic is the strong evidence and its timings are weaker.
Upstream PR #4 and PR #1 (@andrewnakas) and the other prior work were read for behaviour only; see rwaudio-prior-work.md and the credit tables in the specs.
These are working notes. Tags such as [R] (our reading of the code), [IMG] (image constant), [TR] / [T] (trace-checked), [I] (inference) and UNCERTAIN say how firm each statement is. Later findings are added as dated sections; superseded text is marked rather than removed.
Session names (all_20261002_164620, state_20261003_084712.tsv, …) are labels of recordings made during the work; the recordings themselves are local and not published. Scripts named as "local" are not published either; the published ones are under tools/ (doc 14).

Index

Spec	Covers
`aems-reference.md`	Overview: ABKC bank / program layout, evaluator tick, opcode list, sources, corrections; index of the specs below
`aems-evaluator-spec.md`	AEMS patch-program evaluator: bank and MOIR layouts, runtime, all 40 opcodes, timing, RNG, test plan
`aems-voice-graph-spec.md`	Voice graph and output mix: SndPlayer1, resample, filters, gain, pan, sends, buses, output stage
`aems-env-bus-spec.md`	Environment (reverb) bus: send routing, reverb / delay sub-mixes, presets, zones
`aems-eqchain-buses-spec.md`	eEQChain material buses, EQ jitter, LFO task, owner send buses
`aems-bus-leftovers-spec.md`	FlangeSub returns, sense_of_speed FXWET0, Splice Send A, Collision SubMix, reverb zones
`mixmap-spec.md`	MixMap (`MixMapSK8.mxb`): format, evaluation, ambience / emitter outputs, ducking, validation
`grain-player-spec.md`	Granular rolling bed: `grains.big`, surface → grain map, GrainPlayer pick / scheduler / fades, chains
`aems-grain-chain-spec.md`	Board grain bus chain (`sub_824C8878`): FSS, shelf, clip, sends; listening-report evidence
`aems-board-layers-spec.md`	SFXObj_SkateBoard rolling layers: Class_rolling, rattles, board slide
`aems-tricks-treatment-spec.md`	Tricks component (Class_Flips, cloth_trick) and Class_Treatment
`aems-offboard-clothing-spec.md`	Off-board footsteps, clothing, hands-on-deck
`ragdoll-contact-spec.md`	Ragdoll contact response and the bail-sound gap (research)
`ems-emitters-re.md`	World emitters (`.ems`), random one-shot sets, zone ambience beds
`npc-livingworld-re.md`	The living world: census, traffic, pedestrians, security, AI skaters, NPC speech (background for the world audio)
`world-audio-hookin-spec.md`	Design of the engine-facing world audio API and mod surface (doc 15)
`world-traffic-audio.md`	Traffic audio: retail mechanism, port state, hook points
`world-ped-audio.md`	Pedestrian audio: retail mechanism, port state, hook points
`world-speech.md`	Pedestrian speech: data, mechanism, port state
`world-npc-skater-audio.md`	NPC (AI) skaters' board sounds
`rwaudio-prior-work.md`	Prior work on RenderWare Audio and Snd9 AEMS, licences, applicability

Credits

skate3recomp by @mchughalex, built on the rexglue SDK and Xenia's Xbox 360 research; upstream PR #4 and PR #1 by @andrewnakas; sk8Audio (andrewnakas/skate3-audio); BurnoutDecomp's b5-decomp and BP-Decomp_Workflow; dbalatoni13/nfsmw; mitsevox/tw2004; vgmstream. Details and licences per source are in each spec.