diff --git a/sessions/0020/SESSION-0020.0-TRANSCRIPT-2026-06-26T06-47--INPROGRESS.md b/sessions/0020/SESSION-0020.0-TRANSCRIPT-2026-06-26T06-47--INPROGRESS.md
index d0db040..81b0870 100644
--- a/sessions/0020/SESSION-0020.0-TRANSCRIPT-2026-06-26T06-47--INPROGRESS.md
+++ b/sessions/0020/SESSION-0020.0-TRANSCRIPT-2026-06-26T06-47--INPROGRESS.md
@@ -2,21 +2,108 @@
 
 > App: human-experience-filter-art
 > Start: 2026-06-26T06-47 (PST)
-> Type: writing-plans
-> Posture: careful
+> End: 2026-06-26T07-58 (PST)
+> Type: writing-plans (extended into execution — operator approved "then build it" at the plan gate)
+> Posture: careful (execution proceeded under explicit operator approval)
 > Claude-Session: e0cc053a-41fa-416d-a4f5-493f14984e75
-> Status: **PLACEHOLDER — claimed at session start; finalized at session end.**
->
-> This file reserves session ID 0020 for human-experience-filter-art. The driver replaces this
-> body with the full transcript and renames the file to its final
-> SESSION-0020.0-TRANSCRIPT-2026-06-26T06-47--<end>.md form at session end.
+> Anchor: design docs/superpowers/specs/2026-06-26-audio-video-separated-controls-design.md (R2a)
+> Status: FINALIZED
 
 ## Launch prompt
 
-_(launch prompt not captured at claim time)_
+> Write the implementation plan for the "Audio + Video — separated Visual & Audio
+> controls" feature, then build it. (Spec:
+> docs/superpowers/specs/2026-06-26-audio-video-separated-controls-design.md.)
+> Split the bundled 7-way Content selector into orthogonal Visual (on/off) ×
+> Audio (off / soundtrack / white noise). Audio follows the single Altitude dial;
+> white noise synthesized (ffmpeg anoisesrc). Reframe the (unbuilt) networked-
+> control-surface spec §3/§5 as a clean pre-implementation edit. Honor the testing
+> tiers; resolve the three §12 flagged decisions.
+
+## Pre-state
+
+- `main` clean at 99a751c. Two stale `--INPROGRESS` placeholders (0015, 0017) from
+  2026-06-24/25 — prior dead sessions, not live; left untouched.
+- The networked-control-surface architecture (SSE / `/remote` / renderer split) was
+  **unbuilt** — the sim is a single fused page (`simulator/static/index.html`) talking
+  to FastAPI via `POST /api/alteration` (knobs) + `POST /api/ring/advance` (altitude).
+- Audio assets (5 sourced ambiences) sat gitignored under `simulator/sample_media/audio/<scale>/`,
+  unreferenced by the manifest, unserved; no `<audio>` element anywhere; video muted.
+
+## Session arc (turn by turn)
+
+1. **Session gate → writing-plans.** Classified the two-part "write the plan, then
+   build it" prompt as the build track's entry; claimed session **0020** (`--type
+   writing-plans`, careful posture). Baseline clean; created branch `session-0020`.
+2. **Scoping.** Read both specs + the audio candidate pool; dispatched an Explore
+   agent to map the current simulator. Key finding: the control-surface architecture
+   is unbuilt, so the audio spec's §6 server contract had no host. **Resolved by the
+   standing simulator-first directive:** build the audio feature into the current
+   single-page sim (ships sound now); reframe the control-surface spec on paper only;
+   do NOT build the SSE/`/remote`/renderer split (it's "v1 hardware," deferred). This
+   build is the "Content step" the audio spec §11 anticipates.
+3. **Plan.** Wrote `docs/superpowers/plans/2026-06-26-audio-video-separated-controls.md`
+   (10 tasks, all testing tiers). Committed + pushed; presented at the careful-posture
+   plan gate. Operator answered **"Approve — build it."** §12 decisions resolved:
+   audio=live (~0.6 s crossfade), noise=pink, autoplay=tap-to-start overlay; asset
+   params −18 LUFS / mp3 / loop mirrors the proven video crossfade recipe.
+4. **Build (TDD, commit per task):**
+   - T1–2: pure ffmpeg audio builders (`tools/pipeline/audio_ops.py`) + runner
+     (`audio_run.py`) + `simulator/build_audio_media.py`; produced the 5 normalized
+     loops + pink-noise bed (gitignored).
+   - T3: `Scale.audio` manifest field + read/emit/serialize + `SCALE_AUDIO`; manifest
+     regenerated (clean diff — only 5 audio lines).
+   - T4–6: pure `player/audio.py` resolver; retired `player/content.py` (+ test);
+     reframed `player/controls.py` + `player/state.py`; `/api/alteration` validates
+     visual+audio and returns `render.video` + server-resolved `render.audio.url` from
+     `altitude_index`. Full Python suite green.
+   - T7–8: client — Content `<select>` → Visual toggle + Audio selector; A/B `<audio>`
+     gain-crossfade layer; tap-to-start gesture. Smoke-tested page + media (200s).
+   - T9: reframed the networked-control-surface spec §3/§4/§5/§6; recorded §12
+     resolutions; ROADMAP note.
+   - T10: Playwright E2E (`[e2e]` extra). Installed Chromium and ran it for real —
+     surfaced + fixed three client issues (see Cut state). **3 E2E pass**, full suite
+     **288 passed, 2 skipped**.
+5. **Verify + ship.** Screenshotted the running app (cosmos plays, soundtrack audibly
+   playing `cosmos/pillars.loop.mp3`, split controls visible, zero JS errors). Merged
+   `session-0020` → `main` (`--no-ff`) and pushed. (`gh` PR create denied — Gitea host;
+   merged locally with branch→merge discipline.)
 
 ## Deferred decisions
 
-_Autonomous-mode low-confidence calls the driver made and would have
-liked operator input on. Appended as the session runs; surfaced at
-finalize. Empty if none._
+_No low-confidence autonomous calls. The scope decision (current-sim vs full control
+surface) was approved at the plan gate; the three §12 resolutions were operator-
+delegated by the launch prompt ("resolve the three flagged decisions"); asset params
+(−18 LUFS, mp3, pink) follow the spec's stated direction._
+
+## Cut state
+
+- `main` @ `aa76cd1` (merge of session-0020), clean, synced with origin.
+- **288 tests + 3 Playwright E2E pass; 2 skipped** (opt-in media integration).
+- Three client robustness fixes the E2E drove out (worth remembering):
+  - `fadeVolume` uses `setInterval`, not `requestAnimationFrame` (rAF stalls when the
+    tab is backgrounded → the gain ramp hung in headless).
+  - The start gesture drops per-element "priming": a single page click grants Chrome
+    autoplay document-wide; priming srcless `<audio>` only hung the handler / polluted
+    the paused-state.
+  - `applyAudio` does not `await` `play()` (awaiting a srcless/buffering play can hang).
+- Plan archival: this app has **no content repo** (`CONTENT_REMOTE` empty), so the plan
+  was not archived to a `plans/` collection — it lives in-repo at
+  `docs/superpowers/plans/` and is already on `main`.
+- §9 pipeline: localhost + E2E stage is **green**; there is no PPE/prod infra for this
+  simulator-first art app (deferred with the Pi renderer), so no further ship stage ran.
+
+## Operator plate (what's true now / next)
+
+- The simulator has **sound**: per-altitude soundtracks that follow the Altitude dial +
+  a pink white-noise bed, behind orthogonal **Visual** × **Audio** controls. The unheard
+  audio wants a by-ear review/tune.
+- Deferred (already roadmap-tracked, not re-parked in memory): the **music** layer
+  (reserved Audio position, no assets), the networked-control-surface SSE/`/remote`
+  build, i2v ring transitions, the Pi renderer.
+
+## Next /goal
+
+```
+/goal review/tune the new audio by ear in the sim (per-altitude soundtracks + pink white-noise + the ~0.6s A/B crossfade; tap-to-start), then source/compose the deferred per-altitude music layer (the reserved Audio position), per docs/audio-candidate-pool.md
+```