Directly addresses the #7 finding: per-stem PLP grids are weak on sparse-onset stems
(Doors/vocals recall 0.06 vs Gil-Scott-Heron 0.56), because PLP needs onsets to lock a
pulse and a vocal stem barely has them. Fix: find_takes now computes ONE beat grid from
the most rhythmic stem (drums → bass → first available) and reuses it for every stem, so
vocals/other are cut on the same musical bar lines as the drums instead of each guessing
its own. analyze_stem gained an optional `grid=(peaks,times,bpm)` param (None ⇒ per-stem,
the CLI case); find_takes and build_finder_eval both pass the shared grid.

Verified on Loituma: "beat grid from drums" → all four stems analysed on it, including a
cross-stem bass+vocals take at 137s. 8 finder tests (added: analyze_stem honours a shared
grid and adopts its tempo). build_finder_eval re-run with per-track drums grid is in
flight to quantify the recall lift over the 0.27 baseline; the correctness win (shared
grid ≫ weak per-stem grid on sparse stems) holds regardless. Pt.2 (sub-bar chop mode)
remains on #18.

build_finder_eval.py measures whether the loop finder surfaces the windows PLN
actually cut, using the correlation engine's provenance map (#12) as ground truth
at scale. Metric v2: dedup GT into distinct sampled windows (PLN cuts many
overlapping loops per stem), give the finder N≥#distinct candidates so recall isn't
candidate-capped, and also report precision.

Result on the 8 most-cut stems: recall 0.27 (45/169 distinct windows), precision
0.24 — BELOW the 0.70 v1 target. Honest and diagnostic, not a pass:
- The eval picked the hardest stems by design (ranked by #cuts) — CHOP-HEAVY sources
  (14–42 distinct cuts each: Doors, Xxplosive, MC Fioti, Brubeck). PLN chops them into
  short, often sub-bar pieces; the finder targets 2/4/8-bar LOOPS, so it can't
  reproduce sub-bar chops.
- Vocal stems worst (Doors/vocals 0.06) vs rhythmic best (Gil Scott-Heron 0.56): the
  per-stem PLP beat grid is weak on sparse-onset vocals → poor candidate windows.
- Loop choice is taste-driven anyway (house rule: finder suggests, human picks).

Next steps surfaced (new task): (1) borrow the beat grid from drums/full-mix for all
stems; (2) add a sub-bar onset-driven "chop mode". The harness is the katana for both.

Groundwork toward PLN's "merge-of-stems multimodel": the finding that reshaped #9
is that there is NO 4-stem Roformer — all Roformer models are 2-stem; the only
4-stem (drums/bass/other/vocals) separators are the Demucs family. So the immediate,
zero-risk stem-quality A/B is between demucs variants, which the DemucsBackend already
supports via its `model` arg.

Backends now declare a `models` list (demucs: htdemucs / htdemucs_ft / hdemucs_mmi /
htdemucs_6s). /api/backends exposes it; the Foundry GUI gains a model dropdown beside
the engine picker (hidden when a backend has ≤1 model), passed through to /api/separate.
So PLN can now separate with htdemucs_ft (fine-tuned: vocals SDR 10.8 vs 9.9, bass 12.0
vs 11.6) or htdemucs_6s (adds guitar+piano stems) and compare — no new backend.

Verified: build_cmd respects the chosen model (-n htdemucs_ft), /api/backends returns
the list, the selector renders all four. The full multimodel engine2 (Roformer-vocals
+ demucs-rest merged, the door PLN asked to keep open) stays on #9 with the design.

The whole-mix-vs-stem decision (#92) was about to be called on a rigged
comparison. `fit` grades whole-mix on every mix-analyzed track (163 so far,
heading to 534) and `fit --stem` on every stem-analyzed track (24) — different
SETS and different SIZES. The unpaired numbers (calibrated LOO 0.418 whole-mix
vs 0.618 stem) screamed "whole-mix decisively wins," but most of that gap was
sample size: 163 points fit a stable affine (in-sample→LOO gap 0.005), 24 points
overfit it (gap 0.063). That's a sample-size artifact masquerading as a
mode-quality verdict — exactly the kind of premature conclusion the build-the-
katana-first discipline exists to catch.

Approach: extract the raw/in-sample/LOO scoring into a shared `_evaluate()` so
every mode is graded by identical code, then add `paired` — whole-mix vs stem
head-to-head restricted to the slugs analyzed BOTH ways (the only honest
comparison). Reports both modes' raw + calibrated-LOO V/A-err, quad-hit,
emo-hit, plus an in-sample→LOO conditioning gap with an overfit flag.

The surprise (n=26 paired, validated this run): on equal footing the verdict
nearly inverts. whole-mix cal·LOO 0.569 / quad 54% / emo 23% vs stem 0.605 /
58% / 27% — whole-mix wins distance by Δ0.037, but stem wins BOTH quadrant and
emotion-hit, and both overfit (n=26 too small). The honest #92 answer is now
"inconclusive until more stems exist," not "whole-mix decisively wins." Caveat:
the paired subset is the hard cases (first-fetched = aggressive techno/dnb/
dubstep, the high-arousal region drift + the ontology critique both flagged).

Regression: `fit` output unchanged after the refactor. Interim calibration JSON
(n=163 fit) left uncommitted — it regenerates at the full 534.

The Foundry's payoff surface: per separated catch, a "Find loops" button runs the
finder (#5) and lays out its ranked Takes for the human to audition, prune, name,
and forge into a kit — closing the url→stems→loops loop the whole tool was for.

server.py: /api/loops (async job → find_takes → Takes JSON) and /api/export (runs
export_take with the kept stems → Samples/<kit>/, then publish.link_kit). Stems
already serve Range-capable for <audio>.

ui/index.html: a Loops panel. Each Take shows score, bar-count, time window, bpm,
tempo-unstable flag, and a row per stem with: a keep checkbox, role tag, a
dep-free CANVAS waveform of that loop slice (decoded client-side via Web Audio,
cached per stem, drawn in the role colour), a region-audition play button (loops
[start,end] on the full stem via timeupdate), and the candidate score. A kit-name
field (defaults to the slug) + Forge button writes the kept stems and auto-links.

Verified end to end in Chromium (Playwright): Find loops → 8 Takes render, all 11
stem-slice canvases paint (role-coloured waveforms — vocals pink, other cyan, drums
faint where quiet), no console errors. Caveat: first waveform per stem waits on the
full-stem decode (~1s each, 4 stems ~5s); subsequent takes from a cached stem draw
instantly. A future win is byte-range slice fetch instead of full-stem decode.

engine/correlate.py recovers where each hand-cut loop was cut from: a loop is a
literal slice of a separated stem, so normalized cross-correlation of the waveform
has a razor peak at the true offset (true slice ~1.0, foreign ~0.03). build_provenance.py
runs it over the whole corpus → provenance.json.

Result (honest): 482/1690 loops matched (29%) across 28 kits — only the recent
demucs-derived kits have a source in separated/; the rest predate the workflow, and
we quantify that rather than pretend. Recoveries are exact and name-confirming:
bumbum←MC Fioti "Bum Bum Tam Tam", diams_dj←Diam's "DJ", like_sugar←Chaka Khan
"Like Sugar", praise←Fatboy Slim. Cross-stem alignment 0.34 — the measured answer to
§0's open question (loops share a window across stems about a third of the time).

Two bugs caught and fixed during the build, both load-bearing:
- NAIVE all-pairs full-res NCC took 56 MIN on 1690×120. Fix: coarse-to-fine —
  rank every stem by NCC on a frame-RMS *energy envelope* (phase-robust, ~40× cheaper),
  then run the precise sample-domain NCC only on the top-3 candidates. Minutes, not an hour.
- SILENT-WINDOW BLOWUP: catastrophic cancellation in the sliding-variance cumsum
  drove the normaliser to ~0 in quiet stem regions, so silence scored ∞ and
  masqueraded as a perfect match (an early run reported a bogus 55%/0.69 — ~440 false
  positives). Fix: floor the window norm at 5% of the stem's global energy and clamp
  NCC to [-1,1]. Scores are now all ≤1.0 (max 1.000, median 0.969); the honest 29%
  is what survived. Regression test added.

forkserver gotcha: py3.14's default mp start method re-imports the module per worker
(empty globals), so the preloaded-stems COW trick silently fails — pinned mp fork
context. 8 correlate tests (NCC offset/foreign/gain-invariance/silent-window, envelope
prefilter, locate top-k). Feeds the tierlist cut-critique and the finder recall eval (#7).

Recovered the ParVagues loop naming scheme empirically from 1690 existing loops,
rather than inventing one: NN_<role>[_<character>]. The corpus EDA that grounds it
(reproducible via `naming.analyze_corpus`, parsers-over-copy): 46% carry a 2-digit
NN_ index (the hand-cut-kit signature, vs keyed/tempo packs like 120g/80c), 74%
underscore-joined, only 16% repeat the kit name (the folder already carries it), and
the role tokens cluster on voice/vocals, keys, guitar, bass, brass, synth.

naming.py provides:
- suggest_name(index, role, character=, section=) → NN_role[_section][_character],
  slugged + zero-padded + de-duped against names already taken in the kit.
- stem_of(role) → maps a role/character word back to its stem family, so a name
  stays honest to what was actually separated (never infer role FROM the name —
  the finder knows the stem; the name reflects it).
- lint(name) → flags drift (no index, spaces, uppercase, odd chars).
- analyze_corpus() → re-derives the stats above from the live Samples tree.

Wired as export_take's default namer (replaces the inline f"{i:02d}_{name}"), so the
GUI Forge button and CLI export both land convention-compliant names; the GUI's
per-stem name field still overrides. CLI: python3 -m engine.naming --suggest 3 synth dark
| --lint <name> | --analyze. 6 tests; full foundry suite green.

Completes the parked MIDI feature (midimon.py + midistream.py were done/tested in
270a01d6; this wires them into the always-on Bridge). The "do better than a raw
aseqdump in a terminal" monitor now lives in the web dashboard.

server.py: a module-global MidiStream fan-out (lazy — opens aseqdump only while a
tab is watching, closes on the last unsubscribe). Two GET routes:
  /api/midi/ports  → list ALSA seq ports
  /api/midi/stream → Server-Sent Events of parsed events, ?port=addr to pick one.
ThreadingHTTPServer gives each SSE connection its own thread, so blocking on the
subscriber queue is fine; a ': ping' every 15 s holds the pipe open, and
BrokenPipe/ConnectionReset on tab-close is swallowed and triggers unsubscribe.

ui/index.html: a MIDI panel — port picker + connect/disconnect (EventSource) +
rescan, and a live log. Rows are colour-coded by event (note-on green, note-off
faint, control-change amber, pitch-bend magenta), show source/event/channel/
note-name and a velocity bar (val/127), newest on top, capped at 200. Never hue
alone: the event word carries the meaning, colour reinforces (DESIGN principle 4).

Verified end to end: systemd --user restart, /api/midi/ports lists the seq ports,
/api/midi/stream emits ': connected' then live events, and the UI connects (green
"live") and renders rows — no console errors. With no hardware controller attached
the feed shows system/subscription events; note/CC rows appear once a controller
port is selected and played.

PLN flagged the "2024, everything at once" stats as stale. Root cause: the chart
BARS were data-driven but the PROSE around them was frozen string literals
("334 sample folders", "tripled to 14", "2 → 4 → 14 → 14 → 3-so-far", the section
title, the chart tooltips, the magenta-highlight year). They'd drift the moment
the corpus moved. Now every one of them derives from EDA at render:

- breakoutFacts() reads vocabulary_growth + cadence → peak import month/count, the
  breakout year (argmax gigs), the year-over-year multiple, and the gig sequence.
- Story 02's title, dek, legend, note, the magenta band, and both chart tooltips
  are templated from it. parsers-over-copy: no number is typed by hand.
- Honesty fix surfaced by the templating: 4→14 gigs is 3.5×, not "tripled" (the old
  hand-copy undersold) nor "quadrupled" (a naive round oversells). The multiple-word
  only fires when the ratio is within 0.15 of an integer; otherwise it states the
  exact "grew 3.5×". Trust the instrument (DESIGN principle 1).
- New freshness badge in the hero reads EDA.as_of and shows days-since (green ≤14d,
  amber ≤30d) plus the one-line refresh command (python3 tide.py build). Staleness
  is now visible and curable instead of silent — the data is 17 days old today.

Verified in Chromium via Playwright: title/dek/badge all render from data, no
console errors. Follow-up (needs PLN's call): a one-click rebuild from the Bridge
(/api/rebuild → tide.py build) vs the current command hint.

Pre-compact Pass 4: structured long-term-learning entry. The keeper insight —
each grouping grain answers a different question (folder=author's label,
pack=origin, sample=timbre); the origin-vs-sound MISMATCH (15/22 packs span the
family wheel by design) is the story, not an error.

Generates ranked loop candidates from a separated stem, the phase-2 design made
real (PHASE2_FINDINGS §1/§3/§4): drift-tolerant PLP beat grid → beat-sync SSM
(MFCC⊕chroma → recurrence affinity) → Foote checkerboard novelty → candidate
windows at {1,2,4,8} bars → §3 composite score → NMS dedup. Works PER STEM (§0),
then loosely groups candidates across stems by shared time window into Takes the
human auditions together. export_take honours the B-rulebook (B1 ZC-snap, B6 bass
mono-sum, B8 24-bit/44.1k, B10 no-normalize) and calls publish.link_kit.

DRY with the katana: the loopability score reuses engine.grade's seam_score /
zc_score on each candidate slice, and adds the two terms only the finder has the
SSM context for — structural (does the window recur off its own diagonal?) and
boundary novelty (clean segment edges). Weights w_struct .4 / w_novel .2 / w_seam
.3 / w_zc .1, minus a tempo-instability penalty (§3).

Caught while validating on the real Loituma stems: PLP latched onto the eighth-
note pulse and reported ~250 bpm (Loituma is ~125), so 2-bar windows came out
half-length — the §7 octave hazard, live. Fixed by pinning PLP's tempo range to
one musical octave (70–160) and enforcing a min inter-beat spacing in peak-pick.
Now reads ~120 bpm and 2-bar windows land at ~3.9s, squarely in the A-profile
band (3.7–8.0s). find_takes on the 4-stem catch correctly clusters time-aligned
candidates (e.g. vocals+drums sharing a 2-bar window).

CLI: python3 -m engine.loops <stem.wav> [--bars 2 4 8] [--top N] [--json].
7 new tests (checkerboard signs, Foote peak at a block seam, structural recurrence,
NMS dedup, ZC-snap, and the tempo-octave guard). Full foundry suite: 41 pass.

The Foundry Hall of Fame, built through /impeccable in the Ship's Bridge language
(armada/DESIGN.md): dark instrument surface, Geist + Geist-Mono, brand magenta
reserved for the one earned accent (here the S-tier champions, the brand eyebrow,
and the now-playing pulse). Register = product: quiet, instrument-grade, the ear
leads and the screen serves.

What it shows:
- A classic S→D tier board. Tier is encoded redundantly (letter badge + lane
  position + colour), never hue alone — colour-blind safe by construction (DESIGN
  principle 4). Each kit is a chip: median grade, usage (tracks that play it),
  loop count, and a row of flag dots (seam/clip/off-grid/dc).
- Click a kit → a drawer of its loops, each with a grade bar, tier dot, and a
  PLAY button. The ear leads: every loop auditions in place (loop-on-repeat via a
  shared <audio>, _corpus/<kit>/<file>.wav over serve.py), with a now-playing
  footer. (DESIGN principle 2.)
- The rubric-validation callout, shown HONESTLY (principle 1, trust the
  instrument): grade↔usage ρ=+0.34, with a log-scale scatter that *labels its own
  confound* — risers and weird_dialogs sit low-right (used most, tier low) because
  they're FX, not loops. The footnote states the coverage caveat (34/97 kits carry
  a usage token) rather than implying full coverage.
- Search, filter (all/played/flagged), sort (grade/usage/name); skeleton load,
  empty states, focus-visible, keyboard audition, and prefers-reduced-motion
  fallbacks for every animation.

Verified in Chromium at 1280/390 widths via Playwright: no console errors, drawer +
audition + scatter all render, copy carries no em-dashes (impeccable ban). Audio
served through the local _corpus symlink (gitignored). Runs via
`python3 serve.py --dir tide-table --port 8731` → /tierlist.html.

The overnight story: 60→534-track corpus via a 24-subagent workflow (schema-
enforced GT, 0 invalid); cross-model drift (Sonnet relabels all 534) as a
conscience — 72%% quadrant agreement, 174 uncertain-GT tracks concentrated on
circumplex-straddling genres (hardstyle, uplifting trance, neoclassical); and
the unplanned corroboration — a separate ontology-critique panel converged on
the SAME high-arousal gap the drift flagged (groovy/propulsive/transcendent/
menacing). Plus the infra lesson: only a systemd --user unit survives sandbox
teardown. Calibration verdict (whole-mix vs stem at scale) left as the
cliffhanger pending the grind.

A 5-lens Sonnet panel (electronic gaps / canon gaps / synonym enrichment /
overlap-anchors skeptic / cross-cultural) critiqued the 12-emotion wheel:
18 new-emotion, 10 anchor-fix, 10 synonym-add, 2 redundancy proposals.

The signal is the CONVERGENCE:
- 'groovy' proposed independently by 3+ lenses (electronic, canon, cross-cultural)
  — the in-the-pocket body-lock register the wheel has no home for (hypnotic too
  cerebral, playful too cartoonish, warm has no swagger). Clearest accept.
- the high-arousal boundary-straddlers — propulsive (peak-time diesel momentum),
  transcendent (blissed-out rave plateau), menacing (rolling predatory dread) —
  fill EXACTLY the region the cross-model drift report independently flagged as
  uncertain GT (hardstyle's euphoric-aggression, uplifting trance). Two separate
  analyses, same hole: the (+/- valence, high arousal) corner is under-vocabularied.
- bittersweet (melodic-techno's beautiful ache), psychedelic (hallucinatory
  disorientation), plus cross-cultural saudade/duende/ennui (mostly fold into
  existing). dark anchor-fix A+0.20→+0.35 to separate from cold.

NOT folded in tonight: changing the wheel mid-grind would split the corpus across
two ontologies and invalidate the #92 calibration. Expansion + re-analysis is a
deliberate v2 pass (new task). Tonight's corpus stays on the consistent 12.

build_tierlist.py grades EVERY hand-cut loop in the Samples corpus with the Foundry
katana (engine/grade.py — DRY, one rubric) and joins each kit against how often PLN
actually plays it (`s "kit"` track-counts from catalog_view.json). 1690 wavs across
97 loop-kits graded in parallel (~98s, 6 workers). Tiers: 4 S, 3 A, 24 B, 51 C, 15 D.

The point of #11 was never the ranking — it's VALIDATING the rubric against reality
(PHASE2_FINDINGS §5b): do the kits PLN reaches for grade higher? Result:
grade↔usage Spearman ρ = +0.34 — positive, the katana points the right way.

The confound is the interesting part. The single most-used kit, `risers` (16 tracks),
tiers only C — and that's CORRECT: risers are FX sweeps, they go quiet→loud and never
wrap cleanly, so they fail seam + bar-consistency by design. They're heavily used as
one-shot transitions, not loops. Same for weird_dialogs. So loop-mechanical-grade and
usage diverge exactly where they should — for non-loop material. Filtering FX out would
lift ρ; the divergence is a feature (it tells loops from FX), not a rubric failure.
Meanwhile PLN's custom `f*` palette validates the rubric from the other side: fsynth,
fguitar, fmono all land A-tier; fpiano/forgan/fbreak* B. S-tier exemplars: simmons,
electrn, samples-cello-plucked, ouais.

Caveat logged for follow-up: only 34/97 kits matched a usage token (folder name vs
`s`-token mismatch for the rest, and catalog_view covers 73 tracks) — the correlation
is over those 34. The grader's v1 thresholds (noisy dc-offset flag at 1e-4, seam dB
cutoffs) are the next calibration lever now that we can measure against the corpus.

7 pure-logic tests (spearman incl. ties/inverse, usage = tracks-not-occurrences,
tier thresholds mirror the grader). Next: tierlist.html showcase (Ship's Bridge + impeccable).

A second model (Sonnet) independently labeled all 534 tracks; emotion_drift.py
measures where it disagrees with the opus GT. Result:
  mean V/A drift     0.322
  quadrant agreement 72%
  emotion Jaccard    0.53
  174 uncertain-GT tracks (top-quartile drift or quadrant mismatch)

The disagreements aren't noise — they CONCENTRATE on genres that straddle the
circumplex, which is a real finding:
  - hardstyle (The Prophet, Headhunterz): triumphant/euphoric (+,+) vs
    aggressive/tense (-,+) — the genre's 'euphoric aggression' lives on the
    quadrant line.
  - uplifting trance (Cosmic Gate, Ferry Corsten, Markus Schulz): euphoric vs
    driving/tense — same boundary.
  - neoclassical (Nils Frahm, Ólafur Arnalds, Max Richter): calm-positive vs
    melancholic-calm.

So ~33% of the corpus carries genuinely uncertain emotional GT, and it's
predictable WHICH third. Those tracks should be down-weighted (not trusted) in
the upcoming scale calibration — single-model GT would have hidden this.

Overnight scale-up. A workflow fanned 24 opus subagents over genre cells —
electronic-heavy (Detroit/Chicago, modern techno, house, trance, dnb/jungle,
dubstep, garage, ambient, IDM, trip-hop, dub, synthwave, EDM, minimal, French
touch, hardcore, deconstructed, lofi) anchored by canon + diversity (hip-hop,
rock/metal, soul/funk, jazz, world, modern classical). 480 authored → 475 unique
→ 474 merged (1 dup, 0 invalid: schema enforcement on the 12-emotion vocab +
V/A range held perfectly).

Coverage: all 12 emotions, 289 genre tags, every V/A quadrant >> floor (thinnest
--=47). Labels ring true — Cybotron 'Clear' cold/hypnotic, 'Strings of Life'
euphoric, Jeff Mills 'The Bells' hypnotic/tense, de Witte dark/aggressive.

PLN's 'dataset size is the lever' — 9x the corpus for the scale calibration the
n=5/n=60 reads couldn't settle. Audio fetch/analyze runs overnight (disk-safe).

Three tools for the unattended ~6h night run that scales the emotion GT corpus
and validates it across models:

- emotion_corpus_merge.py — fold model-authored GT batches into the corpus
  SAFELY: validate vs the fixed 12-emotion vocab + V/A range, dedup by slug AND
  by normalized artist|title (no track twice under two slugs), default the
  yt-dlp query. Idempotent.
- emotion_overnight.py — disk-safe (volume at 97%%), deadline-bounded grind:
  phase 1 fetch→whole-mix→delete mp3 over the whole corpus (bank the cheap
  signal first); phase 2 re-fetch→demucs stems→delete for as many as the
  deadline allows (grows the #92 stem evidence base). Per-track try/except,
  yt-dlp throttle + consecutive-failure backoff, audio purged after every track.
- emotion_drift.py — cross-model agreement on the GT itself: a second model
  (sonnet) labels the same tracks; high opus-vs-sonnet V/A drift or quadrant
  mismatch flags UNCERTAIN ground truth to down-weight, not trust. Single-model
  GT is a blind spot — a second pair of ears finds it.

Spirit of PLN's overnight brief: scale the dataset (the lever), and check
cross-model drift instead of trusting one model's priors.

A pure grade(wav) -> LoopGrade that scores ANY sample against the empirical
A-profile + the B mechanical rulebook (PHASE2_FINDINGS §2-§3, §5a): seam click,
zero-crossing cleanliness, DC offset, bar-length self-consistency, level sanity,
bass mono-compatibility, and the one-shot/loop class. Composite 0-1 → S/A/B/C/D
tier + per-rule sub-scores + human-readable flags. This is step 1 of the phase-2
build order — the instrument the finder (#5) and the Hall of Fame tierlist (#11)
both reuse (DRY, feedback_build_katana_first): the finder grades hypothetical
windows, the tierlist grades existing files, same sub-scorers.

Two findings while validating against real ParVagues loops (crimewave/diams_dj/humpty):

1. bar-consistency was DEAD — `librosa.feature.rhythm.tempo` doesn't exist in
   librosa 0.11 (it's `librosa.feature.tempo`), so a swallowed AttributeError sent
   every file down the no-tempo fallback → a flat 0.50 for all. Fixed; now crimewave
   drums correctly reads as 4 bars @ 121.9 bpm (matches the GT note ~121.8).

2. seam was measuring the single-sample wrap step |x0-x[-1]| vs the signal's MEAN
   step — which unfairly punishes a loop for wrapping at a zero crossing (the
   steepest point: a *perfect* integer-period sine scored only 0.40). §3 wants
   waveform CONTINUITY, so seam now measures the second difference (jerk) at the
   wrap, |x0 - 2·x[-1] + x[-2]|, normalized by typical curvature — captures both a
   value jump and a slope break, and a clean wrap now grades ~1.0.

Sanity: crimewave (a core-palette kit) lands mostly B-tier or above, with clipping
/off-grid cuts correctly sunk to D — consistent with §5b's "core kits must tier high"
validation target. The composite WEIGHTS + THRESH are tagged v1/provisional: the
dc-offset flag is still noisy (1e-4 is spec-strict) and the seam dB cutoffs want
calibrating — that's #11's job (corpus-wide grade↔.tidal-usage correlation), not
eyeball-tuning on 3 kits. 28 tests pass (synthetic signals, relative assertions).

Runs under system python3 (numpy/scipy/soundfile/librosa already present); no GPU,
no network. CLI: python3 -m engine.grade <wav>… [--json].

Task #8. Question: is a SOTA Mel-/BS-Band Roformer reachable on the 6GB RTX 2060,
or are we stuck on demucs? Answer: it fits comfortably — but the wall was never VRAM.

Run 1 (system python 3.14) died at model instantiation: audio-separator's Roformer
loader carries `Callable | None` type hints that beartype rejects under 3.14
(BeartypeDecorHintNonpepException on `stft_window_fn`). Peak VRAM at crash: 921 MiB —
nowhere near the limit. So engine2 is gated on the interpreter, not the card.

Run 2 (python 3.12 venv) succeeded: bs_roformer_ep_317 separated the 164s Loituma
source in 90s (~0.55× realtime) at a peak of 3051/6144 MiB — half the card, ~3GB
headroom. torch 2.12.1+cu130, onnxruntime-gpu 1.27, CUDA detected fine.

Caveat for the wiring task (#9): ep_317 is a 2-stem model (Instrumental/Vocals); the
Foundry contract is 4 stems (drums/bass/other/vocals). #9 must pick a 4-stem Roformer
checkpoint and re-confirm VRAM — but with 3GB to spare on a 2-stem pass, a 4-stem run
is plausible. The spike is self-contained + idempotent (research/engine2_spike/spike.sh,
SPIKE_PY pins the interpreter); result.json carries the numbers.

The origin-vs-sound mismatch as a feature: a pack defined by where a sound came
from (a song, a machine, a console) is expected to span the family wheel, and
that scatter is the story. Layered grouping discipline = same as the folder: a
hint to compare against, never a law.

PLN's insight: the FOLDER is a loose convention, not the true grouping. rample*
is ONE bank sliced A0..S57; 808* is one drum machine split per voice; *_commodore
is one chip sliced by role. So adds the PACK granularity above the folder —
per-pack / per-folder / per-sample, weakest-to-strongest binding (per-sample stays
the only ground truth).

sample_packs.py: a curated REGISTRY (drum_machine / bank / chip / source / genre)
+ an auto-grouper (prefix-before-digit & underscore head/tail tokens, ≥2 folders)
that PROPOSES packs the registry missed — it caught trance_* and voices_*, now
folded in. A pack needs ≥2 grounded folders (a 1-folder pack is just a folder; it
may gain siblings when #84 grounds all 718 — provenance notes this).

Rolls the per-SAMPLE family counts up to the pack and asks the real question:
does a pack live in one audio family, or span the wheel? 22 packs over 83/150
folders; 15 of them deliberately span multiple families:

  rample  → 8 families (snare/kick/hat/fx/break/pad…) — a bank IS a grab-bag
  jungle  → 11 families — a whole genre's kit
  808     → kick/hat/perc — one machine, three voices
  commodore → bass/fx/pad/lead/synth — the chip, every role

That origin-vs-sound mismatch is the point, not noise: a pack defined by ORIGIN
(a song, a machine, a console) is EXPECTED to scatter across the audio clusters.
Feeds the Unwrapped viz (group-by-pack vs audio-cluster as a story lens) and
vibe-search scoping. Never lets a pack boundary bias the audio analysis — it's a
hint to compare against, never a law.

CLAUDE.md blog-archival rule: commit messages + task logs are blog source
material. This adds the *narrative* layer above the terse armada/tasks/ log —
the documentary 'what happened / what surprised us / what we learned.'

01 tells the emotion-engine story: building CLAP synonym-cluster emotion reads,
the surprise that a 22%% score hid a *systematic* warm-positive center-pull
('playful' fired for 18/60 tracks), and the affine-calibration fix that named
the bias (valence +0.25 too warm, arousal compressed 1.7x) and corrected it
under leave-one-out CV. Includes the n=5 stem-vs-mix call PLN refused to
conclude on — honesty over a clean win.

#91 batch finished — all 60 famous tracks fetched + whole-mix analyzed.
First honest baseline on the full corpus (was n=5 before):

  top-1 emotion hit : 22%   (47% w/ overlap)
  V/A quadrant hit  : 42%
  mean V/A error    : 0.573

The center-compression hypothesis is confirmed at scale: 'playful' is the
predicted top emotion for ~18 of 60 tracks (Fleetwood, Marvin, Coltrane,
Avicii, Journey, Eminem...) because the distribution-weighted mean of the
circumplex anchors collapses toward the warm-positive centre.

Affine de-compression (gt ≈ a·pred + b, leave-one-out CV) learns exactly
that bias and corrects it:
  valence:  ×1.03  −0.25   (reads +0.25 too WARM — the playful pull)
  arousal:  ×1.70  −0.39   (compressed ~1.7x — needs the most stretch)
  LOO V/A err 0.573 → 0.519,  quad 42% → 50%.  Modest but real & cross-validated.

calibrate.py now writes per-mode files (calibration.whole-mix.json /
calibration.stem.json) so the #92 whole-mix-vs-stem decision can compare both
without one clobbering the other; calibration.json mirrors the freshest fit.

Stem-aware batch (demucs, all 60) launched in background to settle #92 on the
full corpus, not the n=5 that PLN rightly refused to conclude on.

New armada/tasks/completed-archive.md — per-task entries with description/done/learnings/
deps + commit hashes, richer than board-archive.md's terse snapshot, written as blog/video
source material. Seeded with this session's completed tasks: #65 (serve.py broken-pipe fix,
d70c3ee7 — keystone audition QOL) and #64 (Information-is-Beautiful dataviz epic + its
craft learnings). Appended by the /pre-compact ritual before clearing the board.

MidiStream fans one aseqdump subprocess out to N web subscribers (SSE), reusing
midimon.parse_line + enrich (one parsing source of truth); reader runs only
while watched (lazy start / stop on last unsubscribe, so no MIDI port held idle).
parse_ports is pure + tested. NOT yet wired into server/UI — see resume task.

Parked mid-feature: server SSE endpoint + dashboard panel still to do.

Clicking L'Armada served armada/ root → a file listing (felt broken). Point it
at armada/tide-table (where the viz lives) and open /triangle.html — same as
`tide.py serve`. Verified: /triangle.html → 200.

Also lands midimon.enrich() (note/velocity/controller→structured) + tests, the
parsing groundwork for the live MIDI dashboard panel.

The hub was dead links (clicking Foundry 404'd — its server wasn't running).
Now it's a real control center, with one shared registry driving both faces.

- launchers.py: allow-listed registry. Web tools (Foundry/Armada) = start-or-open
  via port-check (spawn the server if down, then open); native apps
  (Pulsar/Ardour/qjackctl) launch detached with running + availability state.
  Wayland has no portable focus → running apps report 'already-running'.
- midimon.py: 'aseqdump | tr' done right — parses each event, renders aligned &
  colourised with note names (C4) and velocity bars. parse_line is pure/tested.
- Bridge UI: hub shows live running dots; start-or-open opens a blank tab within
  the click gesture then navigates once the server binds (no popup block).
- perf-tray: 'Open Bridge' + 'Launch ▸' submenu off the SAME launchers.py — the
  tray is now the unified ParVagues tray (DRY with the web hub).
- 17 tests (launcher registry/state + MIDI parser). Verified: Foundry card boots
  the server → :8765 200.

So 'parvagues' is findable in the KDE app menu (the Bridge runs headless as a
systemd service → had no .desktop, nothing to index). Entry opens the dashboard;
ParVagues two-tone wave SVG as the icon. Installed via symlink into
~/.local/share/applications + kbuildsycoca.

Corpus 22→60 tracks, all 4 V/A quadrants now ≥13 (was +-:4, --:2 thin), 50 genres,
all 12 emotions — chosen for confident, balanced priors (quality of pseudo-GT > raw
count for calibration). Added the sad/dark-calm + calm/pleasant fillers (Portishead,
Mazzy Star, Satie, Debussy, Coltrane, Bon Iver…) the gaps report flagged.

emotion_calibrate.py: fits per-axis affine gt≈a·pred+b over analyzed∩GT to DE-COMPRESS
the center-biased CLAP read (learns the scale-up from data, not a guessed tau).
Reports leave-one-out CV error (honest generalization, not in-sample) + re-derives the
label from calibrated V/A (nearest anchor) so we see if labels improve too. Pragmatic
call: scale corpus = whole-mix analysis (demucs doesn't scale to 100s/1k; stems didn't
beat mix on accuracy) — stems reserved for the hexa lane.

- perf-tray.py drops its duplicated Thermals/detect_mode/_read*/MODES/SCRIPT
  and imports them from tools/bridge/perf.py — the tray is now just the Qt face
  of the same logic the web Bridge serves (one source of truth)
- tray icon restyled with the ParVagues signature wave (drawn in Qt, no asset)
  under the heat-coloured temp badge
- parvagues-bridge.service → WantedBy=default.target so it boots headless with
  linger (always-on dashboard, no login needed); tray stays graphical-session
- deployed: bridge enabled+active on :8773, tray restarted, linger enabled

PLN's validation idea: famous tracks whose feeling/structure/genre the model already
knows = pseudo-ground-truth to grade the emotion engine, disagreements driving tuning +
coverage (self-correcting 30→100→300). emotion_corpus_gt.json: wave-1 22 tracks spanning
all 12 emotions + V/A quadrants + genres + structural archetypes (steady / quiet-loud /
long-build); GT = emotion labels + V/A centre + approx fractional section structure +
genre. emotion_corpus.py: fetch (yt-dlp android+bestaudio 403 workaround) → analyze
(demucs+stem-aware or --mix) → grade (emotion-hit, V/A error, quadrant, vocal-presence) →
gaps (coverage histogram → next wave).

BASELINE (whole-mix, 5 tracks): 40% emotion-hit, 40% quadrant-hit, mean V/A err 0.75 —
honest verdict: NOT yet trustworthy. Three systematic biases surfaced: (1) center/positive
compression (extremes pulled to mild +V/+A), (2) 'playful' over-fires (3/5), (3) whole-mix
misses aggression entirely (Prodigy Firestarter→playful +V) — the exact case stem-aware
(drums/bass arousal) should fix. Corpus now drives calibration before the #90 hexa handoff.
gaps: +- and -- quadrants thin, fill at wave 30.

Adds analyze_stems(): separates via foundry_stems (vocals/bass/drums/other), scores
each stem on a shared window grid, fuses V/A by stem role (valence rides vocals+other,
arousal rides drums+bass+mix), and flags vocal presence per window as a structure cue.
Refactor: shared _finalize (smooth→relabel→section→summary) now serves both whole-mix
analyze() and analyze_stems(); embed_at/window_grid/windows helpers extracted.

FINDING (Bohemian Rhapsody, mix vs 4-stem): stem-aware gives a cleaner valence track +
vocal-presence sections (88% vocal; outro correctly reads calm, not 'cold'), BUT the
current arousal fusion UNDER-weights the mix and softened the hard-rock peak that the
whole-mix caught (tense A+0.77 → hypnotic A+0.55) — that section's intensity is a
full-mix gestalt isolated stems lose. So fusion weights need empirical tuning; the
ground-truth corpus (next) drives it. Both modes run end-to-end (#89).

Answers 'is there a ParVagues web service running a dashboard?' — now yes.
Folds perf-tray's function into a web toolbar + extensible fleet hub.

- perf.py: rootless Thermals (hwmon) + detect_mode + sudo-backed set_mode,
  ported from perf-tray.py with Qt dropped (DRY-able with the tray later)
- server.py: stdlib http.server (Foundry lineage); GET/POST /api/perf, /api/hub.
  Binds 127.0.0.1 by default — mode-switch flips the CPU governor via sudo, so
  not LAN-triggerable unless --host 0.0.0.0
- ui/index.html: Ship's Bridge toolbar (live temp badge 55/70/85, mode switch,
  freq/fan/throttle) + hub cards (Foundry :8765, Armada :8731)
- bridge.py CLI (serve/status/perf); parvagues-bridge.service (systemd --user)
- 6 tests on pure perf logic; README incl. deploy + security notes

Smoke-tested: tests green, API live, mode detect + thermals reading correctly.

Stem-aware emotion needs the voice isolated: the full mix is muddy for CLAP, but
the VOCALS carry valence, DRUMS+BASS carry arousal, and vocal presence is itself a
section/structure cue. ensure_stems(file, slug) consumes the Foundry's in-process
Python API (tools/foundry, the shared separation engine) → {mix,vocals,bass,drums,
other} absolute paths, idempotent via catch.json (re-runs free). Validated: 4-stem
demucs separation of a 6-min track (Bohemian Rhapsody) lands all four stems clean.
Feeds emotion_timeline's stem-aware analysis (#89) and the hexa lane (#90).

- README: 'Use as an API' — Python import / CLI subprocess / HTTP API, the
  path+catch.json contract, env overrides (for sibling tools e.g. the #89
  emotional-arc tool that consumes the demucs engine for stems)
- README: add 'link' to CLI reference
- research/{A,B,C}_*.md: the three strand reports (empirical profile,
  fundamentals rulebook, prior-art + recommended zero-dep stack)
- research/PHASE2_FINDINGS.md: strand-D synthesis — corrected per-stem model
  (loops cut per stem, often-but-not-always time-aligned), loopability rubric,
  Take/StemSlice model, correlation engine (§5·0 GT-at-scale), Hall of Fame
  tierlist, section-label grounding (↔ #89), 80/20 build order
- PHASE2_LOOPFINDER.md charter: grounded in the real flow + ground-truth pairs

Windows a master (~12s/50% hop), CLAP-embeds each window (new sample_semantics.
embed_audio_arrays seam), runs the emotion_ontology kernel per window → (valence,
arousal, top-emotion) series; median-smooths, relabels from the smoothed circumplex
point, fuses short runs into emotion SECTIONS. Emits frames+sections+summary JSON —
the continuous-V/A + discrete-scene lane hexa wants. Validated on Bohemian Rhapsody:
caught the warm-intro → energetic-middle → tense rock-peak (A+0.77) → calm-outro arc.

Each emotion is a CLUSTER of angle prompts (adjective pairs + scene metaphors +
bodily framings, EN+FR) marginalized to one robust per-emotion score (mean cosine,
size-invariant) — the synonym→emotion fold mirrors the resolver's descriptor→family.
12 emotions × 6 angles, each placed on Russell's valence/arousal circumplex, so the
distribution yields a continuous V/A point + a discrete top-emotion label.

Per-window kernel: score(ae_row) takes one CLAP audio embed → {scores, dist, top,
valence, arousal, confidence}. Validated: probe archetypes land correctly (melancholic
0.76, aggressive 0.94, hypnotic 0.94, cold 0.72); real-audio path confirmed (pad→
dreamy/melancholic calm). Feeds the planned per-track emotion timeline (hexa lane).

- engine/publish.py: link_kit() symlinks Samples/<kit> → Dirt-Samples/<kit>
  so a freshly-cut kit loads as s "<kit>" (325/508 Dirt-Samples entries are
  this pattern). Idempotent; repoints stale links; refuses to clobber real dirs.
- foundry.py link <kit> CLI; 5 new tests (15 total, all green)
- PHASE2_LOOPFINDER.md: research charter for the loop-finder (Sonnet-agent
  deep-research pass) — grounded in the REAL flow (yt → separated/htdemucs →
  hand-cut → Work/Sound/Samples → ln → Dirt-Samples → .tidal), with the
  crimewave/diams_dj/humpty stem→loop pairs as free ground truth
- README: export target corrected to Work/Sound/Samples + link step

The Sample Foundry: turns a track URL into separated stems ready for
sampling, replacing the manual yt-dlp → demucs → Audacity dance.

- engine/ — pure-ish, importable steps (model/fetch/separate); heavy work
  shells out to dedicated venvs so the engine runs under system python3
- separate.py = pluggable backend REGISTRY: demucs (engine1, live) +
  roformer (engine2, stubbed) behind one --backend interface
- foundry.py — CLI driver (fetch/sep/catch/list/backends/serve), tide.py-style
- server.py — stdlib GUI backend with job-progress + HTTP Range (audio seek)
- ui/index.html — self-contained GUI in the armada Ship's Bridge tokens;
  stems colour-coded by role (bass/drums/other/vocals)
- tests/ — 10 unit tests on the pure parts (slug, info-parse, argv, registry)
- README — workflow, engine1→engine2 roadmap incl. Roformer hyperparams +
  6GB VRAM caveat, phase-2 loop-finder charter, UX surface

Validated end-to-end on the Loituma test catch.