diff --git a/docs/decisions/ADR-0181-audio-compiler-delta-crdt.md b/docs/decisions/ADR-0181-audio-compiler-delta-crdt.md
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+# ADR-0181: CORE-native Audio Compiler over the Delta-CRDT Substrate
+
+**Status:** Proposed
+**Date:** 2026-05-29
+**Authors:** Joshua M. Shay, Core R&D Engine
+**Domains:** `sensorium/audio/`, `sensorium/adapters/audio.py`, `packs/audio/`, `core-rs/src/vault.rs` (read-only contract), `evals/audio_sensorium/`
+**Depends on:** ADR-0013 (Sensorium Multimodal Protocol), ADR-0180 (Delta-CRDT Sharded Substrate)
+**Companion docs:** [audio-compiler-spec.md](../plans/audio-compiler-spec.md), [audio-compiler-eval-plan.md](../plans/audio-compiler-eval-plan.md)
+
+---
+
+## 1. Context & Problem Statement
+
+CORE's sensory boundary is already lawful and text-only-in-practice. `sensorium/protocol.py`
+fixes the contract:
+
+- `ProjectionHead.project(S) -> (32,) float32` is the **Logos-recovery boundary**
+  (`CL41_DIM = 32`).
+- `Modality.AUDIO` already exists in the enum but has no adapter
+  (`sensorium/adapters/` ships `text.py` only).
+- `ModalityPack` enforces gate/checksum invariants at construction; `ModalityRegistry.mount()`
+  runs the unitarity check and `project()` refuses a closed gate.
+
+ADR-0013 (Accepted) requires every new modality to cross this boundary *before* it reaches
+`ingest/gate.py`, and forbids touching `ingest/`, `field/`, `generate/`, `vault/`, `vocab/`
+to add one. Audio must therefore **arrive already compiled** into a `(32,)` Cl(4,1) multivector.
+
+ADR-0180 (Proposed) introduces the **Delta-CRDT sharded substrate** precisely to absorb the
+continuous, high-density streams that audio and vision produce — naming AUDIO explicitly — and
+flags one hard constraint we must satisfy (§1.5.2):
+
+> The semilattice claim holds **only** at the `vault/store` layer — not at `versor_apply`
+> and not at `compute_trace_hash`. … Any operation upstream of `vault/store` that the
+> substrate parallelizes must either (a) be proven order-invariant on its inputs, or
+> (b) carry an explicit serialization barrier.
+
+The problem this ADR solves: **how does audio enter CORE as a lawful, deterministic,
+replayable modality that is also a well-behaved Delta-CRDT delta producer** — without
+violating the no-core-mutation rule, the exact-recall rule, or ADR-0180's order-invariance
+obligation?
+
+The wrong answer is an embedding bridge (CLAP/EnCodec/Whisper as substrate). It produces an
+opaque latent that cannot be checksummed, cannot be replayed bit-for-bit, and cannot supply
+the content-addressed merge key ADR-0180 §1.5.3 demands. The right answer is a **compiler**.
+
+## 2. Decision
+
+We will build `audio_core_v1` as a **deterministic auditory compiler** under `sensorium/audio/`,
+lowering canonical waveform input through a typed `AudioIR` into a `(32,)` float32 Cl(4,1)
+versor, and we will make its **chunk boundary the Delta-CRDT delta boundary**. Learned models
+(Whisper, NeMo, CLAP, EnCodec) are admitted only as subordinate teacher/shadow lanes, never as
+the substrate.
+
+The compilation pipeline (detailed in the spec) is:
+
+```text
+waveform / live stream
+  → canonicalizer    (mono, fixed sample rate, source+canonical sha256)
+  → frame grid       (20 ms window / 10 ms hop)
+  → acoustic lexer   (energy, voicing, onset, pitch candidates, spectral bands, pauses)
+  → typed AudioIR    (speech/pause spans, prosody arcs, turn/overlap events, non-speech atoms)
+  → operator registry (pack-local blade aliases + quantized theta rules)
+  → rotor lowering   (elliptic bivector rotors only in v1)
+  → versor composition (geometric_product → unitize_versor → versor_condition < 1e-6)
+  → (32,) float32    == one AudioCompilationUnit
+```
+
+Normalization sites stay inside CLAUDE.md's allowlist: quantization and FIR resampling live in
+the audio pack/compiler construction boundary, `unitize_versor` is algebra-owned, and **no
+hot-path drift repair is added**. CGA null vectors are preserved as null vectors.
+
+### 2.1 The optimal mapping to Delta-CRDT (the load-bearing decision)
+
+ADR-0180 §1.5.2 gives audio a binary choice for everything the substrate parallelizes:
+**prove order-invariance, or carry a serialization barrier.** The audio compiler answers
+*both*, at two different granularities:
+
+| Granularity | Operation | CRDT treatment | Why |
+|---|---|---|---|
+| **Within a chunk** | `compile_events` (rotor chaining via `geometric_product`) | **Serialization barrier** | The sandwich product is non-commutative (ADR-0180 §1.5.2 row 3). In-chunk composition runs serially, single-threaded, in canonical event order, inside one thread-local arena. |
+| **Across chunks / streams** | merge of `AudioCompilationUnit`s into the Vault | **Order-invariant delta** | Each unit is `(versor, provenance)` written at the `vault/store` layer — the *only* semilattice-eligible layer (ADR-0180 §1.5.2 row 5). Merge is commutative, associative, idempotent. |
+
+This is the synthesis ADR-0180 was waiting for: **the audio chunk boundary is the natural
+delta boundary** named in ADR-0180 §2.2 ("at semantic chunk boundaries"). The compiler does the
+order-sensitive work behind the barrier and emits only order-invariant deltas across it. The
+substrate never parallelizes a non-commutative operation.
+
+### 2.2 Content-addressed merge key from the checksum chain
+
+ADR-0180 §1.5.3 requires the trace-hash reduction to consume vault state in a
+**content-addressed order**, not wall-clock arrival order, or `hash(Sequential_Ingest) ==
+hash(Concurrent_CRDT_Ingest)` cannot hold. The audio compiler already produces exactly this key
+as a byproduct of its layered checksum chain:
+
+```text
+source_sha256 → canonical_sha256 → token_stream_sha256 → ir_sha256
+              → pack_manifest_sha256 → projection_sha256
+```
+
+The **merge key for an audio delta is `(canonical_sha256, ir_sha256, projection_sha256)`**.
+Consequences:
+
+- **Idempotence is structural, not asserted.** Identical canonical bytes under an identical
+  pack produce an identical key; the CRDT join deduplicates them. This satisfies the
+  idempotence leg of the join semilattice (ADR-0180 §2.2) by construction.
+- **The content-addressed sort is free.** The merge kernel orders pending audio deltas by this
+  key. No re-sort pass is needed at hash time for the audio portion of the path.
+- **`projection_sha256` is computed behind the serialization barrier** (§2.1), i.e. on the
+  serialized in-chunk composition — satisfying ADR-0180 §1.5.3 point 3 (upstream-of-Vault
+  hashes must be computed on the serialized portion).
+
+### 2.3 Physical sharding mirrors the audio domain's natural concurrency
+
+ADR-0180 §2.1 assigns each active modality adapter a thread-local arena and forbids
+`sensorium/adapters/*` from writing the global `epistemic_state` directly. For audio this is not
+just a mechanical convenience — it is **semantically aligned**: overlapping speakers,
+interruptions, and turn boundaries (the `B_OVERLAP`, `B_TURN` atoms in the operator table) are
+*literally* concurrent auditory streams. Each concurrent stream gets its own arena; the
+`AuditoryEvent` timing (`start_hop`/`end_hop`) is preserved inside each unit so the merge can
+reconstruct overlap relationships without a global lock during ingestion. The substrate's
+physical sharding is therefore a faithful image of the audio source's structure, not an
+impedance mismatch.
+
+### 2.4 Eventual-consistency window is safe for audio
+
+ADR-0180 §3.2 documents a sub-50ms window where a delta sits in the local arena before merge.
+Audio is robust to this because:
+
+- `ProjectionHead.project` is **pure on the signal** (ADR-0180 T-4) — the audio compiler never
+  reads cross-modal or global state during compilation, so a delayed merge cannot change what it
+  produces.
+- Each unit retains its own intra-stream event timing, so cross-modal resonance re-anchors on
+  merged state after the window closes; recall remains **exact byte-for-byte once merged**
+  (ADR-0180 §1.5.5), never approximate.
+
+### 2.5 Gate-closed by default
+
+`audio_core_v1` mounts with `gate_engaged = false` until the eval gates in the companion plan
+pass. A closed gate makes `ModalityRegistry.project("audio_core_v1", …)` raise — audio cannot
+contribute deltas to any arena until determinism, checksum, unitarity, and mount-validation
+gates are green. This reuses the existing registry enforcement; no new gating machinery is
+added.
+
+## 3. Consequences
+
+### 3.1 Positive
+
+- **First concrete exerciser of ADR-0180.** Audio is the first continuous modality to land on
+  the Delta-CRDT substrate, converting ADR-0180's proof obligation `hash(Sequential) ==
+  hash(Concurrent)` from abstract to testable against real delta producers.
+- **Order-invariance is proven, not hoped.** §2.1/§2.2 give a concrete serialization barrier and
+  a content-addressed key, closing ADR-0180 §1.5.2's open constraint for the audio path.
+- **No core mutation.** Everything new lives under `sensorium/audio/`, `packs/audio/`,
+  `tests/`, `evals/`. `ingest/`, `field/`, `generate/`, `vault/`, `vocab/` are untouched
+  (ADR-0013), and `anti_unifier`/`carrier` need no changes (ADR-0180 §3.1).
+- **Trace hygiene composes.** Turn traces record `(canonical_sha256, ir_sha256,
+  projection_sha256)` and pack IDs — never raw PCM (ADR-0180 §1.5.5).
+
+### 3.2 Negative / Risks
+
+- **Semantic underreach (v1).** The compiler captures prosody, turn dynamics, and salient
+  non-speech events better than lexical content. Acceptable: transcript teachers backfill
+  lexical evidence while the substrate stays native.
+- **Pack ontology drift.** If blade aliases or operator gains change freely, projections become
+  incomparable across versions. Mitigation: the pack is versioned, checksummed, and gate-closed;
+  `basis_version` is part of the merge key's pack-manifest leg.
+- **Over/under-quantization.** Too-coarse bins flatten meaning; too-fine bins make replay
+  brittle. Mitigation: quantization regime is frozen in the manifest and covered by
+  cross-platform stability gates.
+- **Streaming seam artifacts.** Stateful resampling/pitch/overlap must preserve continuity
+  across chunk boundaries. Deferred to the streaming phase; v1 is offline/whole-buffer.
+- **Licensing contamination.** openSMILE's OSS build is non-commercial; it is a reference oracle
+  only, never a runtime dependency.
+
+## 4. Execution Plan & Proof Obligations
+
+### 4.1 PR stack (additive, doctrine-first)
+
+| PR | Scope | Gate |
+|---|---|---|
+| **PR-1 (this)** | ADR-0181 + compiler spec + eval plan (docs only) | review |
+| **PR-2** | Deterministic substrate: `sensorium/audio/{types,canonical,checksum,resample,frames,lexer,parser,operators,compiler,trace}.py` | determinism + versor unit tests |
+| **PR-3** | Pack artifacts `packs/audio/audio_core_v1/*` + `AudioProjectionHead` adapter + mount tests | mount/gate/checksum gates |
+| **PR-4** | `evals/audio_sensorium/` fixtures, expected IR, expected projection hashes | full eval-gate table |
+| **PR-5** | Delta-CRDT wiring: `AudioCompilationUnit` → thread-local arena → merge key, behind ADR-0180's substrate | sequential==concurrent trace-hash proof |
+| **PR-6** | Teacher/shadow lanes (Whisper/NeMo/CLAP/EnCodec) behind optional extras | teachers admitted only as typed hints |
+
+PR-5 must not start until ADR-0180's own §1.5.4 obligations (T-1…T-4) are green on `main` —
+the audio delta path rides on them.
+
+### 4.2 Audio-specific proof obligations (extend ADR-0180 §1.5.4)
+
+Per CLAUDE.md §Schema-Defined Proof Obligations, each must be able to **fail loudly** under the
+violation it names:
+
+- **A-1 (determinism / ADR-0180 T-4 analog).** Same canonical bytes + same pack ⇒ byte-identical
+  `(32,)`, across repeated calls, threads, and processes. Fails if any non-determinism (dict
+  ordering, unpinned FIR, float reduction order) leaks in.
+- **A-2 (set-equality of merges / ADR-0180 T-1 analog).** A set of `AudioCompilationUnit`s folds
+  to the same Vault state regardless of arena flush order (permutation invariance). Fails if a
+  delta's contribution is order-sensitive at the merge layer.
+- **A-3 (content-addressed key / ADR-0180 T-2 analog).** Trace-hash over audio deltas is
+  invariant under set-equal Vault states when keyed by `(canonical_sha256, ir_sha256,
+  projection_sha256)`. Fails if the reduction consumes deltas in arrival order.
+- **A-4 (serialization barrier).** In-chunk `compile_events` is asserted order-sensitive
+  (negative test): swapping two events in canonical order changes the versor. This guards the
+  barrier in §2.1 from silently becoming commutative and masking a real ordering bug.
+- **A-5 (versor condition).** Every emitted unit satisfies `versor_condition(v) < 1e-6`; the
+  threshold is never weakened to pass.
+- **A-6 (trace hygiene).** No raw waveform bytes appear in any `TurnEvent`/Vault record; only
+  the three hashes + pack IDs + optional teacher provenance.
+
+### 4.3 The strict compilation invariant
+
+```text
+same canonical audio bytes
+  + same compiler version
+  + same pack manifest (incl. basis_version)
+  + same operator registry
+= same AudioIR
+= same versor
+= same projection hash
+= same CRDT merge key
+= identical post-merge Vault contribution (idempotent under re-ingest)
+```
+
+The final clause is the ADR-0181 addition to the PDF's original invariant: determinism is not
+only replayability, it is **CRDT idempotence** — the property that makes audio safe to shard.
+
+## 5. Alternatives Considered
+
+- **Transcript-first cascade (Whisper as substrate).** Chunked, text-intermediate; discards the
+  auditory structure (the "No." vs "No?" vs whispered "no" distinction) and produces no
+  checksummable, content-addressed key. Rejected as substrate; retained as teacher.
+- **Embedding-first projector (CLAP).** Fast but opaque; cannot be replayed bit-for-bit and
+  cannot supply ADR-0180 §1.5.3's content-addressed merge key. Rejected as substrate.
+- **Codec-token front end (EnCodec / Moshi-like).** Strategically interesting for future
+  full-duplex output; poor first substrate for an epistemically explicit engine. Deferred to a
+  shadow/output lane.
+- **Audio as a downstream cognition mutation.** Violates ADR-0013's no-core-mutation rule and
+  ADR-0180's "adapters never write global state directly" rule. Rejected.
+
+## 6. Cross-References
+
+- ADR-0013 — projection boundary; no-core-mutation constraint.
+- ADR-0180 — Delta-CRDT substrate; §1.5.2 order-invariance constraint (closed here for audio),
+  §1.5.3 content-addressed merge key, §1.5.4 T-1…T-4 (audio analogs in §4.2), §1.5.5 trace
+  hygiene & no hidden background execution.
+- ADR-0054 — Vault recall indexing/batching; the read-side contract the merged audio deltas must
+  preserve (exact CGA recall).
+- CLAUDE.md §Normalization Rules — quantization/FIR confined to pack/compiler construction;
+  `unitize_versor` algebra-owned; no hot-path repair.
+- `sensorium/protocol.py`, `sensorium/registry.py` — the `ProjectionHead`/`ModalityPack`/
+  `ModalityRegistry` contracts this ADR implements an audio instance of.
diff --git a/docs/plans/audio-compiler-eval-plan.md b/docs/plans/audio-compiler-eval-plan.md
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+# Audio Compiler Eval Plan — `audio_core_v1`
+
+**Companion to:** [ADR-0181](../decisions/ADR-0181-audio-compiler-delta-crdt.md),
+[audio-compiler-spec.md](./audio-compiler-spec.md)
+**Status:** Proposed (PR-1 docs)
+
+This plan defines the seeding corpus, the acceptance gates that lift `audio_core_v1` from
+gate-closed to gate-engaged, the Delta-CRDT proof obligations, and the teacher-migration policy.
+
+---
+
+## 1. Seeding corpus — auditory atoms, not transcripts
+
+Small, curated, checksum-locked. Four tiers:
+
+- **Tier A — speech & turn atoms:** silence, short/long pause, voiced/unvoiced speech, onset,
+  offset, interruption, overlap, rising/falling contour, emphatic energy.
+- **Tier B — prosody & affect:** calm, urgent, uncertain, whispered, shouted, sorrowful, joyful,
+  irritated, sarcastic-like contours where reliably labelable.
+- **Tier C — non-speech events:** laughter, sigh, cry, alarm, knock, impact, keyboard, water,
+  traffic, animal call, music bed, broadband noise.
+- **Tier D — alignment anchors:** spoken phrase, timestamp span, transcript hypothesis,
+  speaker/channel metadata, linked text surface (only when alignment is trustworthy).
+
+Tier D is auxiliary; lexical semantics is a later enrichment step. Synthetic fixtures (sine
+bursts, chirps, impulses, periodic voiced surrogates, silence, controlled overlaps) drive
+first-pass determinism; checksum-locked real fixtures cover what synthesis does poorly
+(laughter, sigh, whisper, interruption, yes/no rising-pitch questions).
+
+## 2. Acceptance gates (gate-engaged criteria)
+
+| Gate | Pass criterion |
+|---|---|
+| Projection shape | exactly `(32,)` |
+| Projection dtype | exactly `float32` |
+| Compiler replay | bit-identical on same platform/build |
+| Cross-platform stability | equal after quantization, within declared numeric tolerance |
+| `versor_condition` | `< 1e-6` (never weakened) |
+| Canonical checksum stability | 100% on fixture corpus |
+| Gate closure | projection blocked when `gate_engaged = false` |
+| Mount validation | bad checksum or bad unitarity blocks pack mount |
+| Trace hygiene | no raw waveform bytes in any turn trace |
+| IR replay | `AudioIR -> versor` replays identically from stored IR |
+
+These mirror the existing modality-test posture (`sensorium/registry.py` mount/gate enforcement,
+`ModalityPack.__post_init__` invariants).
+
+## 3. Delta-CRDT proof obligations (ADR-0181 §4.2)
+
+Each must be able to **fail loudly** under the violation it names (CLAUDE.md §Schema-Defined
+Proof Obligations — no decorative tests):
+
+| ID | Obligation | Fails if… | ADR-0180 analog |
+|---|---|---|---|
+| **A-1** | Determinism: same bytes + pack ⇒ byte-identical `(32,)` across calls/threads/processes | dict ordering, unpinned FIR, or float reduction order leaks in | T-4 |
+| **A-2** | Set-equality of merges: a set of units folds to the same Vault state for any arena flush permutation | a delta's contribution is order-sensitive at the merge layer | T-1 |
+| **A-3** | Content-addressed trace-hash: invariant under set-equal Vault states when keyed by `(canonical, ir, projection)` sha | the reduction consumes deltas in arrival order | T-2 |
+| **A-4** | Serialization barrier: in-chunk `compile_events` is order-sensitive (negative test) | swapping two canonical-order events fails to change the versor | T-3 |
+| **A-5** | `versor_condition < 1e-6` on every emitted unit | the threshold is weakened to pass | — |
+| **A-6** | Trace hygiene: no PCM in any `TurnEvent`/Vault record | raw waveform leaks into a delta's provenance | §1.5.5 |
+
+### 3.1 The sequential==concurrent proof (PR-5 acceptance)
+
+The load-bearing test for the CRDT mapping:
+
+```text
+ingest fixtures [c1, c2, c3] sequentially      → vault_seq,  trace_hash_seq
+ingest the same fixtures across N arenas merged → vault_conc, trace_hash_conc
+assert set(vault_seq) == set(vault_conc)                       # A-2
+assert trace_hash_seq == trace_hash_conc                       # A-3
+assert re-ingesting any fixture is a no-op on the vault        # idempotence (ADR-0181 §4.3)
+```
+
+This is the audio instance of ADR-0180 §4.3's `hash(Sequential_Ingest) ==
+hash(Concurrent_CRDT_Ingest)` and must pass before PR-5 merges.
+
+### 3.2 Pytest skeleton
+
+```python
+def test_audio_projection_is_deterministic(audio_fixture, audio_pack):       # A-1
+    v1 = audio_pack.projection.project(audio_fixture)
+    v2 = audio_pack.projection.project(audio_fixture)
+    assert v1.shape == (32,)
+    assert v1.dtype.name == "float32"
+    assert np.array_equal(v1, v2)
+
+def test_audio_pack_gate_blocks_projection(audio_pack_closed, audio_fixture):  # gate closure
+    with pytest.raises(Exception):
+        _ = audio_pack_closed.projection.project(audio_fixture)
+
+def test_audio_ir_replay_matches_original(audio_fixture, compiler):            # IR replay
+    unit = compiler.compile(audio_fixture)
+    replay = compiler.compile_ir(unit.audio_ir)
+    assert np.array_equal(unit.versor, replay.versor)
+    assert unit.ir_sha256 == replay.ir_sha256
+
+def test_chunk_composition_is_order_sensitive(two_events, compiler):           # A-4 barrier
+    a = compiler.compile_events([two_events[0], two_events[1]])
+    b = compiler.compile_events([two_events[1], two_events[0]])
+    assert not np.array_equal(a, b)
+
+def test_merge_is_permutation_invariant(units):                                # A-2
+    import itertools, random
+    states = {fold_into_vault(p) for p in itertools.islice(_perms(units), 8)}
+    assert len(states) == 1
+```
+
+## 4. Teacher / shadow lane policy (PR-6)
+
+Teachers label or align; they **never** define the substrate and **never** fold embeddings into
+the main versor path. They are admitted only through typed, versioned, checksummed hints stored
+as `content_anchors` / `evidence_ids` in the IR.
+
+| Source | Best role in CORE | Why not the substrate |
+|---|---|---|
+| **Whisper** | offline transcript evidence, weak lexical labels, language ID | chunked, text-intermediate; loses native auditory structure |
+| **NeMo Parakeet** | timestamp/alignment teacher, live evidence lane | ASR, not a CORE-native auditory compiler |
+| **NeMo Canary** | streaming multilingual transcript/translation evidence | useful evidence, wrong primary ontology |
+| **CLAP** | coarse sound-event labels, audio-text alignment prototypes | embedding model; opaque latent violates the design goal |
+| **EnCodec** | reconstruction shadow lane, transport, future speech-to-speech output | codec tokens ≠ lawful typed auditory operators |
+| **Moshi** | latency / full-duplex reference target | codec-token speech modeling, not deterministic IR→versor |
+| **openSMILE / eGeMAPS** | reference feature catalog / offline oracle | OSS build is **non-commercial**; reference only, never a runtime dep unless licensing cleared |
+
+Migration policy, verbatim:
+
+```text
+Use teachers to label or align.
+Never let teachers define the substrate.
+Never fold teacher embeddings directly into the main versor path.
+Only admit teacher outputs through typed, versioned, checksumed hints.
+```
+
+## 5. Phased sequence (priority order, no calendar)
+
+1. **Doctrine** — ADR + spec + eval plan locked (PR-1, this).
+2. **Deterministic substrate** — canonicalizer, checksums, resample, lexer, parser, operators,
+   compiler (PR-2).
+3. **Governance** — pack artifacts, adapter, mount/gate/checksum tests (PR-3).
+4. **Evaluation** — fixtures, expected IR, expected projection hashes, gate table (PR-4).
+5. **Delta-CRDT wiring** — arena + merge key + sequential==concurrent proof (PR-5), gated on
+   ADR-0180 §1.5.4 (T-1…T-4) green on `main`.
+6. **Auxiliary lanes** — Whisper/NeMo/CLAP/EnCodec teachers behind optional extras (PR-6).
+7. **Streaming** — stateful incremental compiler preserving continuity across chunk seams
+   (later; v1 is offline/whole-buffer).
diff --git a/docs/plans/audio-compiler-spec.md b/docs/plans/audio-compiler-spec.md
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+# Audio Compiler Spec — `audio_core_v1`
+
+**Companion to:** [ADR-0181](../decisions/ADR-0181-audio-compiler-delta-crdt.md)
+**Status:** Proposed (PR-1 docs)
+**Scope:** the deterministic substrate (PR-2/PR-3) and its Delta-CRDT delta interface (PR-5).
+
+This spec fixes the typed intermediate representation, the operator/manifest format, the numeric
+determinism rules, and the `AudioCompilationUnit` → Delta-CRDT delta contract. It is
+implementation-facing; the *why* lives in ADR-0181, the *acceptance* lives in the eval plan.
+
+---
+
+## 1. Two-clock architecture
+
+A low-level **acoustic clock** measures signal facts; a higher-level **auditory grammar clock**
+emits typed events. The primary path is fully deterministic; learned systems are confined to
+auxiliary evidence lanes (PR-6).
+
+```mermaid
+flowchart LR
+  A[Waveform bytes / live stream] --> B[Canonicalizer<br/>mono + fixed SR + checksums]
+  B --> C[Frame grid<br/>20 ms window / 10 ms hop]
+  C --> D[Acoustic lexer<br/>energy, voicing, onset,<br/>pitch candidates, spectral bands, pauses]
+  D --> E[Typed AudioIR parser<br/>speech/pause spans, prosody arcs,<br/>turn/overlap events, non-speech atoms, anchors]
+  E --> F[Canonical ordering<br/>quantization + stable serialization]
+  F --> G[Operator registry<br/>pack manifest + blade aliases + theta rules]
+  G --> H[Rotor lowering]
+  H --> I[Versor composition<br/>unitize_versor + versor_condition]
+  I --> J["(32,) float32 — one AudioCompilationUnit"]
+  E --> K[Audio evidence trace<br/>hashes, teacher provenance, pack IDs]
+  J --> L[Thread-local arena<br/>ADR-0180 §2.1]
+  L --> M[Semilattice merge<br/>keyed by content-addressed sha]
+```
+
+## 2. Typed AudioIR
+
+The IR is built from **typed spans and events**, never from raw frames or mel bins. Transcript
+anchors may exist only as auxiliary content hypotheses, never as the sole meaning of the audio.
+
+```python
+from __future__ import annotations
+from dataclasses import dataclass
+from typing import Literal
+import numpy as np
+
+
+@dataclass(frozen=True, slots=True)
+class AudioSignal:
+    samples: np.ndarray        # canonical mono float32
+    sample_rate: int           # 24_000
+    start_ms: int
+    end_ms: int
+    source_sha256: str
+    canonical_sha256: str
+
+
+@dataclass(frozen=True, slots=True)
+class PitchCandidate:
+    cents_q: int               # quantized cents
+    prob_q: int                # 0..255
+
+
+@dataclass(frozen=True, slots=True)
+class AudioToken:
+    kind: Literal[
+        "silence", "voiced", "unvoiced", "onset",
+        "energy_bin", "pitch_candidates", "spectral_bin",
+    ]
+    start_hop: int
+    end_hop: int
+    value_q: tuple[int, ...]   # canonical quantized payload
+
+
+@dataclass(frozen=True, slots=True)
+class AuditoryEvent:
+    event_type: str
+    start_hop: int
+    end_hop: int
+    attrs: tuple[tuple[str, int | str], ...]
+    evidence_ids: tuple[str, ...]
+
+
+@dataclass(frozen=True, slots=True)
+class AudioIR:
+    speech_spans:     tuple[AuditoryEvent, ...]
+    pause_spans:      tuple[AuditoryEvent, ...]
+    prosody_arcs:     tuple[AuditoryEvent, ...]
+    turn_events:      tuple[AuditoryEvent, ...]
+    non_speech_events: tuple[AuditoryEvent, ...]
+    content_anchors:  tuple[AuditoryEvent, ...]
+    ir_sha256:        str
+```
+
+### 2.1 The compilation unit (the CRDT delta)
+
+```python
+@dataclass(frozen=True, slots=True)
+class AudioCompilationUnit:
+    canonical_sha256:  str
+    ir_sha256:         str
+    pack_id:           str
+    pack_manifest_sha256: str
+    projection_sha256: str
+    versor:            np.ndarray   # (32,) float32
+    versor_condition:  float
+
+    @property
+    def merge_key(self) -> tuple[str, str, str]:
+        # ADR-0181 §2.2 — content-addressed CRDT merge / dedup key.
+        return (self.canonical_sha256, self.ir_sha256, self.projection_sha256)
+```
+
+`AudioCompilationUnit` is the single object the audio adapter writes into its thread-local arena
+(ADR-0180 §2.1). It carries no PCM (ADR-0181 §3.1 / ADR-0180 §1.5.5).
+
+## 3. Canonical signal formation
+
+- Internal processing: **mono, 24 kHz, float**; original-source bytes preserved separately for
+  provenance; a derived 16 kHz stream is produced **only** for teacher ASR (PR-6).
+- Resampling: **pinned polyphase FIR** (SciPy `resample_poly` semantics — zero-phase,
+  odd-length symmetric filter). The FIR coefficients are generated **once**, stored as a pack
+  artifact (`resample_fir_v1.npy`), and checksummed in the manifest. The runtime never relies on
+  library defaults.
+
+## 4. Acoustic lexer
+
+Operates on **measured facts**, not semantic guesses. Default frame 20 ms / hop 10 ms. Each
+frame yields quantized descriptors: RMS/log-energy bin, voiced/unvoiced flag, candidate F0 set
+(pYIN-style: multiple candidates with probabilities **before** Viterbi smoothing), onset
+strength bin, coarse spectral centroid/tilt bin, zero-crossing regime, pause classification.
+
+## 5. Parser → typed events
+
+Promotes lexer output into typed spans/events. Preserves the distinction between "No.", "No?",
+shouted "No!", whispered "no", and silent hesitation. Non-speech atoms (laughter, alarm, impact,
+music, broadband noise) are first-class; "chaotic noise" is the fallback only when a more
+specific parse is impossible.
+
+## 6. Operator registry (pack-local blade aliases)
+
+Because the `(32,)` boundary is fixed but no canonical *semantic* blade map is exposed, v1 uses
+**pack-local, versioned, checksummed blade aliases**. v1 uses **elliptic bivector operators
+only** (square = −1), so every rotor uses the numerically well-behaved
+`R = cos(θ/2) + B·sin(θ/2)`. Hyperbolic/boost-like operators are deferred.
+
+| Auditory atom family | Measured source | Alias | Default blade index | Theta rule |
+|---|---|---|---|---|
+| Speech present | voiced frames / harmonic ratio | `B_SPEECH` | 6 | `q(base + g1·voiced_ratio_q)` |
+| Short pause | pause duration | `B_PAUSE_SHORT` | 7 | `q(base + g2·dur_hops)` |
+| Long pause | pause duration | `B_PAUSE_LONG` | 8 | `q(base + g3·dur_hops)` |
+| Rising final contour | final F0 slope | `B_PITCH_RISE` | 9 | `q(base + g4·slope_q)` |
+| Falling final contour | final F0 slope | `B_PITCH_FALL` | 10 | `q(base + g5·abs(slope_q))` |
+| Emphasis / force | energy delta | `B_EMPHASIS` | 11 | `q(base + g6·delta_db_q)` |
+| Hesitation / uncertainty | filled pause + low-conf contour | `B_HESITATION` | 12 | `q(base + g7·hesitation_q)` |
+| Turn boundary | silent gap + local reset | `B_TURN` | 13 | `q(base + g8·boundary_q)` |
+| Overlap / interruption | simultaneous speech / abrupt cut | `B_OVERLAP` | 14 | `q(base + g9·overlap_q)` |
+| Alert-like event | salience / alarm morphology | `B_ALERT` | 15 | `q(base + g10·salience_q)` |
+| Laughter | periodic burst pattern | `B_LAUGH` | 16 | `q(base + g11·laugh_q)` |
+| Cry / distress | voicing + modulation profile | `B_DISTRESS` | 17 | `q(base + g12·distress_q)` |
+| Music / tonal bed | stable harmonic bed | `B_MUSIC` | 18 | `q(base + g13·tonal_q)` |
+| Chaotic broadband noise | flat/noisy spectrum | `B_NOISE` | 19 | `q(base + g14·noise_q)` |
+
+Indices are **reasonable defaults, not metaphysical claims** about Cl(4,1). The contract is that
+the mapping is explicit, versioned, checksummed, and frozen in the manifest. `B_OVERLAP` and
+`B_TURN` are the atoms that motivate per-stream arenas in ADR-0181 §2.3.
+
+### 6.1 Minimal manifest (`packs/audio/audio_core_v1/manifest.toml`)
+
+```toml
+pack_id = "audio_core_v1"
+modality = "audio"
+cl41_dim = 32
+compiler_version = "0.1.0"
+basis_version = "audio-basis-v1"
+
+[canonical]
+sample_rate = 24000
+channels = 1
+frame_ms = 20
+hop_ms = 10
+output_dtype = "float32"
+internal_dtype = "float64"
+
+[resampling]
+algorithm = "polyphase_fir"
+fir_path = "resample_fir_v1.npy"
+fir_sha256 = "sha256:REPLACE_ME"
+padtype = "constant"
+cval = 0.0
+
+[gating]
+gate_engaged = false
+checksum_verified = false
+versor_condition_max = 1.0e-6
+
+[ordering]
+event_precedence = ["channel", "pause", "speech", "prosody", "turn", "non_speech", "content_anchor"]
+```
+
+### 6.2 Operator row (`operators.jsonl`)
+
+```json
+{
+  "operator_id": "audio.prosody.question_contour.v1",
+  "event_type": "prosody.question_contour",
+  "blade_alias": "B_PITCH_RISE",
+  "blade_index": 9,
+  "rotor_kind": "elliptic",
+  "base_theta_q": 64,
+  "gain_rules": {"slope_q": 3, "final_energy_q": 1, "confidence_q": 1},
+  "theta_clip_q": 384,
+  "version": "1"
+}
+```
+
+## 7. Numeric determinism
+
+Rule: **quantize before semantics, normalize after composition.** Raw float measurements are too
+unstable to hash. Quantization regime (frozen in manifest): boundaries in hop units, log energy
+in 1 dB bins, F0 in 25-cent bins, pitch slope in coarse cents-per-100 ms bins, spectral shape in
+fixed ordinal bins, all confidences in uint8. After quantization, compute in float64, compose
+sparse rotors in canonical order, call algebra-owned `unitize_versor`, cast to float32 **only**
+at the output boundary.
+
+```python
+import math
+import numpy as np
+
+EPS = 1e-12
+
+def quantize_theta(theta: float, step: float = 1.0 / 1024.0) -> float:
+    return round(theta / step) * step
+
+def build_elliptic_rotor(blade_index: int, theta: float) -> np.ndarray:
+    out = np.zeros(32, dtype=np.float64)
+    half = quantize_theta(theta) / 2.0
+    out[0] = math.cos(half)
+    out[blade_index] = math.sin(half)
+    return out
+
+def compile_events(events, registry, geometric_product, unitize_versor, versor_condition):
+    # SERIALIZATION BARRIER (ADR-0181 §2.1): in-chunk composition is order-sensitive,
+    # single-threaded, canonical order. The substrate never parallelizes this loop.
+    v = np.zeros(32, dtype=np.float64)
+    v[0] = 1.0
+    for ev in events:                          # must already be in canonical order
+        spec = registry[ev.event_type]
+        theta = spec.theta_from_event(ev)      # deterministic, quantized inputs only
+        r = build_elliptic_rotor(spec.blade_index, theta)
+        v = geometric_product(v, r)
+        v = unitize_versor(v)
+    if versor_condition(v) >= 1e-6:
+        raise ValueError("audio compilation failed versor check")
+    return v.astype(np.float32)
+```
+
+`geometric_product`, `unitize_versor`, `versor_condition` are imported from `algebra/` — the
+audio compiler adds **no** new normalization function.
+
+## 8. Repo-facing adapter (`sensorium/adapters/audio.py`)
+
+```python
+from __future__ import annotations
+from dataclasses import dataclass
+import numpy as np
+
+@dataclass(frozen=True, slots=True)
+class AudioProjectionHead:
+    compiler: "AudioCompiler"
+    modality = ...                # Modality.AUDIO
+
+    @property
+    def embedding_dim(self) -> int:
+        return 32
+
+    def project(self, signal: "AudioSignal") -> np.ndarray:
+        unit = self.compiler.compile(signal)
+        out = unit.versor
+        if out.shape != (32,):
+            raise ValueError(f"expected (32,), got {out.shape}")
+        if out.dtype != np.float32:
+            raise TypeError(f"expected float32, got {out.dtype}")
+        return out
+
+    def project_batch(self, signals: list["AudioSignal"]) -> np.ndarray:
+        return np.stack([self.project(s) for s in signals], axis=0)
+
+    def verify_unitarity(self, signal: "AudioSignal") -> bool:
+        return self.compiler.compile(signal).versor_condition < 1e-6
+```
+
+The adapter is thin and pack-governed; it satisfies the `ProjectionHead` protocol in
+`sensorium/protocol.py` and is mounted as a `ModalityPack(modality_type=Modality.AUDIO,
+gate_engaged=False)` until the eval gates pass.
+
+## 9. Delta-CRDT delta interface (PR-5)
+
+The audio adapter **never** writes the global `epistemic_state` (ADR-0180 §2.1). Instead:
+
+1. `compile()` produces one `AudioCompilationUnit` per canonical chunk (the serialization
+   barrier of §7 runs here).
+2. The unit is written lock-free into the adapter's **thread-local arena**. Concurrent streams
+   (overlap/interruption) each have their own arena (ADR-0181 §2.3).
+3. The **Merge Kernel** (ADR-0180 §2.2, an explicitly-mounted component, not a daemon — ADR-0180
+   §1.5.5) folds pending units into the global Vault ordered by `unit.merge_key`. Duplicate keys
+   are deduplicated (idempotence).
+4. The kernel surfaces its pending-delta count in `TurnEvent` for replay evidence (ADR-0180
+   §1.5.5).
+
+The per-chunk Vault contribution is `(versor, provenance)` where provenance =
+`{merge_key, pack_id, pack_manifest_sha256}` — content-addressed, no PCM.
+
+## 10. File plan (PR-2 … PR-6)
+
+```text
+sensorium/audio/{__init__,types,canonical,checksum,resample,frames,lexer,parser,operators,compiler,trace,fixtures,teachers}.py
+sensorium/adapters/audio.py
+packs/audio/audio_core_v1/{manifest.toml,basis_map.json,operators.jsonl,atoms.jsonl,prototypes.jsonl,resample_fir_v1.npy,checksums.json}
+tests/test_audio_{signal,resample,lexer,parser,compiler,pack_manifest,sensorium_mount,trace,crdt_delta}.py
+evals/audio_sensorium/{fixtures/*.wav,manifest.json,expected_ir.jsonl,expected_projection_hashes.json}
+```