skate-3-rust-engine/docs/hails-additions/11-audio.md

11 — Game audio (ambience, rolling, trick cues, footsteps, water)

Branch: gameplay/audio (from gameplay/water 477e9de), uncommitted. Status: implemented and tuned by ear over ~15 play sessions with the user (2026-10-01). Most cues are confirmed in play; the rest are marked not yet confirmed below. All sample choices are project choices, not retail event data.

Problem

The engine made no sound of its own. Only Lua mods could play audio (crates/skate-game/src/modding/audio.rs, PCM WAV through Bevy's bevy_audio). Skate 3's sounds are on the owned disc but nothing extracted or decoded them.

What is on the disc

Everything audible is under data/audio/. All archives except music/overlays.big are EB BIG v3 archives readable with tools/owned_game/big.py.

Archive	Contents
ambience.big + ambienceresident.big	24 per-area ambience beds (.sns bodies, .snr headers), e.g. 04_dt_main, 09_univ_campus; 5-channel 48 kHz, ~2–2.5 min loops
audiofiles.big	376 ABKC .abk banks, 20 SPLC .bnk banks, 23 per-map .ems emitter files, 9 MOIR .csi AEMS event scripts
grains.big	14 rolling "grains", 7 surfaces × soft/hard wheels (asphalt_smooth, asphalt_rough, concrete_smooth, concrete_rough, concrete_aggregate, wood_ramp, metal_smooth hard only) + x_jet_rolling
wheels.big	Whls_spins_Jump_1, Whls_spins_Man_1 (+ .sek seek tables)
post.big, nis.big, english/…, music/…	stingers, speech, cutscenes, licensed music — not used

Formats (worked out from the archives; tools/asset_pipeline/audio_formats.py)

• Codec: every sample is an EA SNR (EAAC) stream with codec 3 = EA-XMA (Xbox 360 XMA2), mostly mono 48 kHz (also 44.1, 36, 24 and 22.05 kHz).
• SNR header: u32 version(4)|codec(4)|channels-1(6)|rate(18), u32 type(2)|loop(1)|samples(29), optional u32 loop start. RAM streams are followed by blocks of u8 flag (0x80 = last), u24 size, u32 samples.
• SPLC .bnk: stream count at 0x18, 36-byte parameter records, then that many SNR streams back to back at unaligned offsets. The scanner finds exactly the declared count in all 20 banks (2,266 streams).
• ABKC .abk: embedded SNR streams; the scanner's count matches vgmstream's subsong count for all 376 banks (5,168 streams).
• .grain: u32 offset of the SNR stream, f32 duration (matches samples/rate exactly), a .sek-style seek table, then one SNR stream. Each recording is a slow-to-fast rolling sweep: over 17–22 s it gets ~10 dB louder and brighter (e.g. concrete_smooth_hard −24 → −14 dBFS, centroid 0.9 → 2.0 kHz), so looping the whole file sounds wrong.
• 5-channel ambience order is L, C, R, Ls, Rs (from inter-channel correlation).
• .csi (MOIR) event scripts name events, classes and variables (play_grind_start, Class_Flips, Ollie_Rattles, surface_type, playercharacter_footstep, body_imp_Torso, …) in 16-byte records (name offset, 16-bit id, default value). The banks hold no per-sample names; linking events to samples would mean re-implementing EA's AEMS runtime, which this change does not do.
• Retail mixes at runtime: many raw samples peak at 0 dBFS with RMS up to −6 dBFS, so playback levels must be low; footstep recordings are the opposite (peak ≈ −11 dBFS, RMS ≈ −28 dBFS).

Change — current design

Setup: new audio asset group

• tools/asset_pipeline/audio_formats.py — SNR scanner/validator (block-chain check), SPLC and grain readers, standalone .snr cut-out, gain-free 5→2 downmix (weights per output sum to 1), loopable band cutting for grains.
• tools/asset_pipeline/audio_export.py — decodes only what the engine plays to PCM16 WAV in assets/private/audio/ with audio_manifest.json (version 2): 22 ambience beds (stereo), 14 grains cut into 6 loopable speed bands each (84 files, 0.08 s loop cross-fade), 2 wheel spins and 23 sample banks (2,718 samples). No normalisation or gain. ~40 s, ~615 MB.
• Decoder: vgmstream r2117 (vgmstream-win64.zip, SHA-256 6c4a8a38…dc6c, matching GitHub's published digest), downloaded and verified by the existing install.dependency() into data/tools/vgmstream-cli/. It bundles FFmpeg's XMA2 decoder (LGPL DLLs). vgmstream reads SNR/SNS and ABKC itself but not SPLC or grain files, so every stream is cut out to a standalone .snr first and decoded in batches of 256 (one vgmstream run stops accepting input files between 600 and 1,100 arguments).
• Registered as group audio (versions.py GROUPS/SOURCES, group_receipts.py ROOTS, asset_exports.audio, install.py). Optional content: a failed download or decode records assets/private/audio-availability.json and setup still succeeds; the game then runs silent. Existing installs refresh only this group.
• .gitignore: retail audio extensions and *.wav (except the Skyline Drive mod's own WAVs).

Engine: crates/skate-game/src/game_audio/

File	Role
mod.rs	AudioSettings (master 75 % by default — 100 % is unity gain; 25 % (−12 dB) was too quiet to judge retail parity in play, user 2026-10-02 —, ambience 100 %, effects 100 %, 5 % steps) saved to settings/audio.json; menu rows in GRAPHICS; --mute; GlobalVolume follows the master so mod audio obeys it; the single SpatialListener (moved out of modding/audio.rs) follows the gameplay camera; preloads every cue sample, grain band, wheel spin and water piece at startup (~207 clips, ~35 ms) so riding never reads the disk.
library.rs	Loads the manifest; reads WAVs into Assets<AudioSource>, measuring each clip's peak; rejects paths outside the audio folder; warns once per missing file.
voices.rs	Voice pool and loudness rules (below). Everything pauses while the menu is open or a replay runs.
cues.rs	The sample table, per-cue minimum gaps, metal-surface test, surface → grain table.
skate_events.rs	observe (FixedUpdate, after each physics tick) turns state changes into cues; play (Update) plays them and drives the loops (rolling, grind, powerslide, foot drag, wheel spin).
ambience.rs	One bed per map, level 0.6, 2 s cross-fade on map change.
water.rs	Water emitters from the map's water collision.

Outside the module (observation only; physics never reads any of it):

• physics/animation_input.rs — AudioEvents latch. push_contact (flags bit 27), brake_contact foot-down/up (bits 28 + 30 / 23) and AudibleFootStepStrength are cleared within the tick (finish_output_publication, ScalarAttributeInputs::reset), so they are latched while the animation attributes are processed and taken by observe.
• physics.rs foot_clearance — each animated foot's height above its ground line test (via biped_ground::services::feet_input).
• skate-core WheelLineState.audio_surfaces — audio surface (surface_tag & 0x7F) per wheel, next to the existing physics_surfaces. Additive output only.

Loudness rules (voices.rs)

• A requested volume may raise a quiet clip only until the clip's own peak reaches full scale, and never more than ×4; category and master volumes (both ≤ 1) then scale it down. No clip plays hotter than full scale × master.
• One-shots start at their final level on the first sample; loops and sounds that ask for a fade start silent and fade in (≥ 10 ms). (Until 2026-10-01 every sound faded in and its gain was raised once per frame from 0, which ate the attack of 25–35 ms impacts and knocks — pops and landings lost their layering.) Retail layer offsets are kept with Record::delay (frame-granular). At most 32 voices, 3 of one sound, same sound again only after 40 ms; each cue also has a minimum gap (cues::min_gap: step 0.2 s, run step 0.15, push 0.3, bail 0.5, splash 1.0, others 0.12) as a safety net against flags that stay set for many ticks.
• One-shots get a random ±4 % pitch. Spatial attenuation scale 0.1 (Bevy's attenuation never amplifies).

Cues (as in cues.rs / skate_events.rs now)

"Level" is the cue level in cues.rs; the scale column multiplies it. Fraction = board speed / 10 m/s.

Cue	Trigger (per physics tick)	Samples	Level × scale	In play
Pop	ground_animation.launched rising	retail recipe: knock 1112 + 878 + 891 at once, crack 1096 + one of 1097-1099 at +20 ms, body 1111 +30 ms, low thud 876 +40 ms (traced offsets)	retail median × 2	Rebuilt from 57 traced pops + captured sound; not yet confirmed
Flip / grab whoosh + catch	new trick name while airborne (a held grab re-announced by scoring stays silent)	Sk8_Air_Flip_Tricks 1–3 (retail's Class_Flips) + container 1115 (feet catching the board)	0.45 / 0.8	Retail mapping new
Land	filtered category Air → Ground, air not begun on foot; impact = riding.ground.maximum_closing_speed	container 1095 (wheels down, ~1 s) + impact family 1055 / 1058 / 1052 by impact (< 3, < 6, ≥ 6 m/s)	(0.6; 0.5 / 0.64 / 0.72) × (0.3 + 0.7·impact/12)	Retail mapping new; the impact-family choice is ours
Board down	Air → Ground when the air phase began on foot (on foot within the last 0.5 s)	container 1126 (foot on deck) + 1119 (knock) + 1054 (wheel touch)	(0.6 / 0.54 / 0.28) × (0.3–1.0 over 0–5 m/s)	Retail mapping new
Board down heavy	same, impact > 2.5 m/s ("caveman" jump-on)	+ landing set 1095	0.6 × (impact − 2.5)/4	Retail mapping new
Grind	grinds.grinding_316 or a grind state, and not leaving_317	start: container 954 (ledge etc.) or 1146 (metal rail object); then metal: GRINDS 54–56 loop; other surfaces: container 955 pieces (202–206) re-fired every 63 ms	start 0.5 / 0.8, loop 0.26, pieces 0.3; × (0.5 + 0.5·fraction)	Retail mapping new
Powerslide	state 101 SlideGround: random piece every ~0.08 s (±20 %), 10 ms fade-in	WHEEL_SKID_BANK 0–7	0.2 × fraction	Not yet confirmed
Foot drag	between brake_contact foot-down ticks (ends at foot-up or 0.1 s after the last foot-down), riding on the ground above 0.5 m/s; piece every ~0.11 s, 50 ms fade-in	FOOT_DRAG 36–39, 44–47, 60–64	0.25 × (0.3 + 0.7·fraction)	Confirmed
Push	push_contact rising edge	fstep_skateshoe1_sm 74–84	0.6	Plays at a sane rate (no flood); sound not judged separately
Step / run step	foot strike (below) while on foot (states 500/501) and moving > 0.3 m/s; run set above 3 m/s	fstep_skateshoe1_sm 74–84 / 6–17	0.85 / 0.68 × (AudibleFootStepStrength/4, 0.3–1.0)	Confirmed ("almost perfect")
Bail	entering WipeoutGround (300), not in water and no splash in the last 0.5 s; tier by body speed (≥ 3.5 / ≥ 7 m/s)	body hits container 1074 (records 667–671) + Bodyslide 0–4 / 5–9 / 10–15 layer	0.52 × (0.6 / 0.8 / 1.0) + 0.25	Bodyslide tiers heard as right; body hits = retail mapping, new
Splash	body water contact (collision_feedback.flags.material_12) rising while falling > 1 m/s (1.5 s cooldown); or entering a wipeout in water with no splash in the last 1 s (speed ≥ 2)	Skate_Collisions 476–478	0.5 × (0.4 + 0.6·speed/8)	Confirmed (found by the user); the wading-wipeout path not yet confirmed
Rolling (loop)	wheels in contact, not grinding, > 0.3 m/s; grain by majority wheel audio surface; speed band	grains/<surface>_hard/<band>	0.15 × min(speed/1.5, 1)	Confirmed
Wheel spin	take-off above 1 m/s, cut on landing (0.05 s)	Whls_spins_Jump_1	0.15 × fraction	Not yet confirmed

Rolling bands: board speed is low-passed (0.25 s) and mapped over 0–10 m/s to the 6 bands; the band changes only when the speed is a full band away and after ≥ 1 s on the current one; changes cross-fade over 0.15 s, and within a band the pitch follows speed by ±6 %. A new surface must stay under the wheels 0.25 s before the grain changes; after 0.15 s off the ground the loop stops and restarts directly on the surface it lands on.

Footsteps: FootStrike (in skate_events.rs) learns each foot's resting clearance (follows the lowest value, drifts back up over ~2 s) and fires when a foot that lifted > 5 cm above rest comes back within 2 cm. AudibleFootStepStrength only scales the volume.

Surface → grain (cues::grain_for, audio surface names from the map tooling's _AUDIO_NAMES, tools/vendor/university/…/owned_world_material_addon/__init__.py): 1 asphalt_smooth; 2 asphalt_rough; 4, 66 concrete_rough; 5, 8, 10, 55, 56 concrete_aggregate (aggregate, dirt, grass, leaves, bush); 6, 7, 41–46, 90 wood_ramp; metal IDs → metal_smooth; everything else (Concrete_Polished = 3, curbs, tile, marble, unlisted) concrete_smooth. Only the "hard" grains exist for every surface, so those are used; retail was measured playing the same "hard" grains (concrete_smooth/wood_ramp/asphalt_rough/metal_smooth).

Measured retail mapping (2026-10-01)

The pop/flip/landing/board-down/grind/bail cues above use the retail SPLC patches that a local recompiled build of the game (github.com/mchughalex/skate3recomp, built and run locally only, no code taken) was measured playing for the same moments. The recomp was instrumented to log every sample start with its final gain (gain modules × send), every SPLC patch request with the gameplay function that asked, and every audio-object post; the user played normally while it logged, and the events were grouped by the game's own requesting function. Exact moments came from a scripted ollie/kickflip:

time after the flick	retail plays
+0.24 s (pop)	containers 1096 + 1098/1099, flip object (Sk8_Air_Flip_Tricks 1–3)
+0.3–0.6 s (catch)	deck knocks 1112 / 1115 / 1118 (548–552 + 530–535)
+0.95 s (landing)	1095 (396–404, ~1 s) + one impact family of 1052/1055/1058 + wheel skid
getting on the board	1126 (422–426) + 1054 + 1095 + knock 1119

Measured levels (linear, retail mix): knocks 0.36–0.57, pop/landing sets 0.2–0.46, board-down 1126 up to 0.76, ledge grind pieces ≤ 0.35, rail start 0.49, bail hits ≤ 0.26, Bodyslide ≤ 0.19, GRINDS ≤ 0.13, rolling grains p90 0.065. Our levels = retail × 2.0 (cues::RETAIL_SCALE), calibrated so retail's rolling level lands on our play-tested ROLL_LEVEL. Not decoded yet: how retail picks among the impact families 1050–1059 (surface/force); we choose by impact.

Water emitters (water.rs)

On map load, water collision triangles (type 12) are grouped into bodies by shared vertices and sampled on a 6 m grid; each body is classed by area. The nearest point of each body is the emitter, placed ≤ 8 m from the listener in its direction (panned, Bevy attenuation stays 1) with its own distance fade ((1 − d/reach)^1.5). At most one body per kind and three in all; Ambience volume; random pieces with a 0.4 s fade-in.

Kind	Area	Bank (pieces 0–9)	Level, reach	Interval
Fountain	< 400 m²	water_fountain (moving/splashing water)	0.45, 25 m	0.6–1.1 s
Canal	< 30,000 m²	water_lapping	0.4, 40 m	0.7–1.3 s
Lake	larger	water_lapping_pond	0.45, 60 m	0.7–1.3 s

University: 7 bodies (6 fountains, 1 lake); DownTown: 25 (12 fountains, 13 canals). The fountain bank replaced a still-water lapping loop after the user's comment; not yet confirmed in play.

Ambience per map (project choice by bed name; retail switches beds by zone via .ems files)

Map	Bed
University	09_univ_campus
StartPark	10_univ_housing
DownTown	04_dt_main
DownTownSkatePark, MegaPark	05_dt_parks
Industrial	11_indu_shipyard
IndustrialSkatePark	20_indu_old_factory
SkateSchool	18_skate_school
MaloofMoneyCup	21_interior_arena_amb
BlackBoxPark	22_interior_tunnel_amb
Test world	none

"Ambience good so far" (user, University); other maps not yet judged.

Logging (always on)

• AUDIO_CUE <cue> <bank>:<index> volume=… for every one-shot ((voice limit) if refused).
• AUDIO_LOOP start <file> for rolling/grind/water loops, AUDIO_LOOP start <name> (<bank>) for shuffles.
• AUDIO_EVENT brake down|up, push, grind start|stop surface= ledge= flag= leaving=, rolling surface= grain= band= (on change only).
• Startup: Game audio: 22 ambience beds, 14 rolling grains, 23 sample banks, Game audio: preloaded N clips, Ambience: <bed> for map …, Water audio: N bodies (…).
• SKATE_AUDIO_TRACE=1 adds per-tick AUDIO_TRACE lines (footstep strength, push/brake flags, foot heights).

Dev tools

• py -3.13 tools/audio_audition.py → .local/audio-audition/index.html: every cue's current samples (parsed from cues.rs), each bank in full grouped into runs of similar clips, grains and beds; players at 25 % volume; links the installed WAVs, copies nothing.
• cargo run -p skate-data --release --example audio_surfaces -- <map.skate> lists audio surface IDs per map; with AT=x,y,z[,r] it lists the collision surfaces (audio ID, physics type, slope) within r m (default 3) of a point, e.g. a HUD position the user reports.

Retail patch records (SPLC) and prior work upstream

• Prior work: upstream PRs #4 ("Audio/retail exact player sound") and #1 (an earlier snapshot of it, plus a procedural vehicle-engine synth) run retail's AEMS sound routing through a function-by-function transcription of recompiled game code and a dumped TU3 memory image. That runtime conflicts with this fork's rule (re-implement; disassembly is reference only; no game code/data), so it is not used. Their format notes were used as knowledge, re-derived and verified here.
• SPLC patch tree (audio_formats.splc_patches): 60-byte header (+8 sample-table offset from byte 60, +12 records, +16 containers, +20 extras = 0, +24 samples); 36-byte records (+4 id, +7 group count); 72-byte containers (+4 record ids, +68 count, +69 mode); per record its groups (12-byte header: +8 member count, +9 mode) of 72-byte members (+0 sample index, +8 gain, +44 pitch spread, +48 gain range, +64 probability; +20/+52 delay, not used yet). Verified on all 20 SPLC banks: the walk ends exactly at the sample table, every member names a valid sample (5,973 members → 2,266 samples), and sample-table offsets sit at a constant distance from our SNR scan — SPLC sample index n is our stream n.
• Semantics (per PRs #1/#4, implemented independently in skate_events.rs play_record): a record's groups are layers played together, one member each; group mode 0 random, 1 in sequence, 2 shuffled without an immediate repeat; a member plays unless rand > probability; gain ± range; pitch random between 1/s and s for spread s > 1; ids ≥ the record count are containers that pick one record.
• Validation of the ear-picked samples: every group the user picked is exactly one retail record in Skate_Collisions: pop 1074–1078 = record 818, landing 1088–1092 = records 824/825, heavy 1097–1100 = records 832/833, board-down 0/1/2 = records 125/126/127, splash 476–478 = part of record 869.
• Splash now plays record 869 (three layers: 169 at 75 % probability + one of 476–478 + one of 171/172).
• Setup exports each SPLC bank's patch tree in audio_manifest.json (patches, manifest v3).
• PR #4's own pop/landing ids are different, layered patches (e.g. container 1097 → records 745–750, each 5 single-member layers from 260–267 / 635–657 / 1000–1015); they come from game tuning values we do not read. Not adopted; the user's picks stay.

How it was tuned (condensed session history)

Each step came from the user's report of an in-play session plus the AUDIO_* log lines of that session.

1. First pass: push, foot drag, footsteps silent — the animation events are cleared inside the tick before any ECS system can see them → AudioEvents latch. Bails silent (board_wiping_out is reset by the ground phase) → WipeoutGround state. Grinds silent (raw category_12) → player_state.current().
2. Flood: the next log showed push fired 1,723 times and steps ~60/s: push contact and AudibleFootStepStrength stay set for many ticks. That flood caused scratchiness, odd pick-up sounds and likely the hitches (now fixed). → rising edges, per-cue minimum gaps, preloading.
3. Footsteps: a SKATE_AUDIO_TRACE=1 run showed AudibleFootStepStrength is a held level (2.5–4, higher when running), not a step event; a peak detector fired only when the level changed. → foot strikes from foot clearance (planted 0.02–0.04 m, swing up to 0.4–0.55 m; 56 steps over ~16 s at ~6 m/s). Footstep clips are ~10 dB quieter than impacts → the headroom rule replaced "volume ≤ 1".
4. Foot drag: brake_contact foot-down repeats every tick while braking (47 and 139 ticks seen), then foot-up repeats while lifting (24–28 ticks); bit 28 is set by both, so the first latch also dragged on foot-up. → drag only between foot-down ticks, above 0.5 m/s, overlapping 0.2 s scuffs.
5. Rolling: grain files are speed sweeps → 6 bands. Then 53 restarts in one session (band jumps right after landings, concrete seams flickering) → smoothing, holds. On University's plywood ramp the sound "played twice": AT= confirmed the ramp is audio 41 (Wood_1) throughout, so the mapping was right; 36 of 38 quick restarts were band changes → switch only a full band away, ≥ 1 s per band. Remaining doubling at low speed: on returning to the ramp the loop restarted on the debounced old surface (concrete) and switched to wood 0.25 s later → stop after 0.15 s off the ground and restart on the surface underneath. User: "much better".
6. Board down: every touch-down after stepping on played land, because the physical state leaves BipedGround a few ticks before the filtered category reaches Air → "began on foot" = on foot within 0.5 s; level by impact (0.18–0.45 m/s seen for gentle set-downs).
7. Deck family (found by the user): the user picked out Skate_Collisions 1066–1092 as "noises heard a lot while skating". Measured: 0.13–0.37 s knocks, most energy at 400–2500 Hz (the deck), unlike the low thumps either side (1060–1065, 1093–1100; 70–90 % of energy under 400 Hz). Pop = sharpest (1074–1078, 5–20 ms attack); land = 1088–1092; weight = 1097–1100. User: pop and landing "10000% better". Earlier rejected landings: 35–40 (harsh), 18–20.
8. Splash (found by the user): a full decode of all 7,434 streams scored for splash shape found no long splash; candidates (water_misc, Skate_Collisions 741–762) were rejected ("not water related at all"). The user found Skate_Collisions 476 ("literally a splashing noise") on a candidate page; 477–478 are its variations (same length 1.6–2.0 s and spectrum). 473–475 (shorter) were tried for small falls and rejected → always 476–478. Each water entry also played a bail ~20 ms later → bail suppressed in water. Wading in then falling gave no fresh fast contact → a wipeout in water splashes by itself.
9. Grinds: sound followed the named state, which lags the selector → grinding_316 / leaving_317. A University rail sounded like wood: Skate_Metal has no clip ≥ 1 s, so GRINDS (123 clips, 1.4–2.6 s) holds every material. By tonality (energy share of the strongest 1 % of spectral bins) 9 and 11 are among the least tonal (0.30–0.36), 54–56 the most tonal and brightest (0.65–0.85, 4–5.6 kHz) → 54–56 on metal.
10. Bail: Bodyslide 0–15 is three blocks of five (one longer slide + four hits), heard as rising impact → tiers. In play they sound like additions to a fall, not the body impact → kept as a quiet sweetener layer (0.25) until a main impact is chosen (.local/audio-audition/bail.html; EA's scripts name body impacts per body part: body_imp_Torso, _leg, _Head, _foot).
11. Grab whoosh repeated while holding a grab (3 in 0.8 s): scoring re-announces a held grab with the same name → whoosh only for a new name in the air phase. Confirmed.
12. A game window that closed with no report was Windows Terminal crashing (the game was attached to its console via PLAY.bat), not the game.

Files

• New: tools/asset_pipeline/audio_formats.py, audio_export.py, test_audio_formats.py, tools/audio_audition.py, crates/skate-game/src/game_audio/{mod,library,voices,ambience,cues,skate_events,water}.rs, crates/skate-data/examples/audio_surfaces.rs.
• Changed: tools/asset_pipeline/{asset_exports,install,versions,group_receipts}.py, tools/asset_pipeline/test_versions.py and tools/test_setup_assets.py (hand-written group lists), crates/skate-core/src/physics/board_ground.rs (+ test), crates/skate-game/src/{main,app,config,graphics_menu,physics}.rs, physics/animation_input.rs (audio event latch), modding/audio.rs (listener moved), retail_character.rs and tests/map_transition.rs (Config.mute), .gitignore.

Verification

• test_audio_formats (synthetic streams only); setup tests 42/42; all tracked tools tests identical to the clean tree (the same 3 pre-existing import errors).
• Every SPLC bank: scanner count = declared count; every ABKC bank: scanner count = vgmstream subsongs.
• cargo test: game_audio (cue table sanity, bail tiers, band hysteresis, foot strikes, board-down levels, water bodies and fade, voice limits, headroom), graphics_menu, modding::audio, map_transition, skate-core board_ground.
• Export into the dev install: 22 beds, 14 grains (84 bands), 2 wheel spins, 23 banks; --check-assets → SKATE_ASSETS_READY.
• Muted smoke runs (--mute): the startup lines above, no panics, errors or missing-sink warnings.
• ~15 in-play sessions by the user (University, DownTown); confirmed items are marked in the cue table.
• Not yet done: full regression-check pass and a setup refresh through the installer path (only the audio group should rebuild).

Open questions

• Main bail body-impact sound (Bodyslide is only a layer); landing weight layer level; metal grind pick (54–56) by ear; powerslide, wheel spin, push sound, fountain bank, caveman jump-on — not yet confirmed.
• Some surface → grain choices may be off; soft vs hard grains are probably wheel hardness (only hard used).
• Retail plays rolling granularly; this plays banded loops.
• Zone ambience from .ems emitters (beds per map are a name-based guess); manual wheel spin (Whls_spins_Man_1); music.
• ~615 MB of PCM (mostly ambience): a compressed format would need an encoder at setup.
• Retail's own sample choices could be measured from a recompiled build that logs which bank data the game decodes (local research only, not part of this change).
• AUDIO_* logging is verbose for a release build.