feat(copycat): deep drum rework from onset+envelope analysis

Full NTO drum character applied:
- d1 kick: att 0.05 (round thud), lpf darkening over time (saw 800→300)
- d2 clap: quiet (gain 0.7), dry (room 0.1), hpf 800 — mid-snap only
- d3 OH: evolving brightness (n6→n8), att 0.04 (soft onset),
  ^44 toggles whisper-shimmer mode (gain 0.3, hpf 6000, legato 0.15)
- Header: full drum voice analysis with centroid evolution,
  attack/decay times, peak levels per section

copycat/la_cle_des_champs.tidal

@@ -60,22 +60,40 @@
 -- 0-10s:   Pad only (other stem: Bb3, rms=0.07)
 -- 10-30s:  Bass enters (86Hz/F2, rms=0.19-0.26), pad continues
 -- 30-50s:  Arp synth fades in (guitar stem: 172-183Hz), piano first stabs
--- 50-60s:  Build (all melodic voices growing)
--- 60-90s:  Drums enter big (kick 54Hz/93% sub at 65Hz), full groove
--- 90-120s: Piano peaks (237Hz, rms=0.05), all voices at full
--- 120s:    Breakdown — bass drops to C2 (65Hz), arp peaks, drums thin
--- 150s:    Piano reprise, mid-frequency evolution
--- 200s+:   Climax sections, pad shifts bright (560Hz), full energy
+-- 40-50s:  KICK enters — 8th note pulse, kick only, no hats yet
+-- 60s:     OH enters on upbeat 8ths (warm, centroid 4000Hz)
+-- 70-80s:  Full groove: K↑OH alternating 8ths, OH brightening (→4900Hz)
+-- 90s:     Pre-drop: kick gets ghost DOUBLES, OH→ride brightness (→7700Hz)
+-- 90s bar4: KICK DROPS OUT — pure cymbal shimmer (centroid 8200Hz, QUIET)
+-- 100-120s: Cymbal break — whisper-quiet shimmer on upbeat 8ths only
+-- 150s:    Kick returns + OH-mid (centroid 6000Hz), groove restored
+-- 200s+:   Full: kick + bright OH/ride + CLAP on beats 1&3 (contretemps)
+--
+-- DRUM VOICES (demucs onset + envelope analysis)
+-- ================================================
+-- KICK: dom=86Hz, sub=58-70%, att=48-56ms (SLOW round thud), dec=3ms
+--   No click, no snap. Gets DEEPER over time (centroid 1100→200Hz).
+--   Pattern: 8th notes on every downbeat eighth. Ghost doubles pre-drop.
+--
+-- OPEN HAT → CYMBAL (one evolving voice, not separate samples):
+--   centroid evolves: 4000Hz(warm) → 4900(bright) → 8400Hz(shimmer)
+--   Groove: peak=0.55-0.61, att=38-42ms, on every upbeat 8th
+--   Breakdown: peak=0.05-0.07 (QUIET whisper!), att=7-10ms (tick)
+--   Post-drop: peak=0.62, centroid 6000-7200Hz (bright ride character)
+--
+-- CLAP: enters at climax (~200s), contretemps (beats 1&3)
+--   peak=0.13 (quiet accent!), att=10ms, dec=12ms, dom=1292Hz
+--   Dry thin mid-snap. Not a fat backbeat — more rimshot/finger snap.
 --
 -- SOUND DESIGN
 -- ============
--- KICK:     54Hz/93% sub (demucs). Deep techno sub-kick, NOT a bright 808
--- BASS:     Bb1-F2 sub (58-87Hz). Moog-like, melodic root movement + answer
--- ARPEGGIO: 2-note 16th Bb4↔F4, FM synth. Magic = timbre not notes
--- PIANO:    Rhodes stabs, Bb3/F4 area, enters ~40s, peaks at 90s
--- PAD:      ~Bb3 warm bed, evolves brighter. Generous reverb, slow filter
--- HATS:     h2o velocity-layered, sparse offbeat + flourish
--- CLAP:     h2o natural handclap, reverbed
+-- KICK:     Round sub thud (att 50ms!), 8th pulse. Gets deeper over time.
+-- BASS:     F2/A2/C2 (V chord tones only!). Rhythmic, not held notes.
+-- ARPEGGIO: 2-note 16th Bb4↔F4, FM synth. Magic = timbre not notes.
+-- PIANO:    Rapid A3/F3 repeated stabs (16th-ish), sparse, enters ~40s.
+-- PAD:      ~Bb3 warm bed, evolves brighter. Generous reverb, slow filter.
+-- OH/CY:    One voice that brightens: warm OH → bright ride → shimmer.
+-- CLAP:     Late entry (~200s), contretemps, dry quiet mid-snap.
 --
 -- NTO'S KNOWN GEAR:
 --   Moog Subsequent 37, Arturia MicroFreak, Akai APC40 MKII,
@@ -105,50 +123,50 @@ let gM3 = gMask . gMute3
 -- Main Bbm/F vamp with Db/Ebm variation
 -- Demucs evidence: bass at Bb1(58Hz)/F2(87Hz), C2(65Hz) passing tone at breakdown
 let rt = slow 2 "<bf2 f2 bf2 f2 bf2 f2 df2 ef2>" -- root sequence (for d6 piano, pad, etc)
-d1 $ gF1 $ gMute2 -- KICK: 8th note pulse (demucs: kick on EVERY downbeat 8th)
-  -- NTO pattern: kick+OH alternating 8ths, NOT 4otf!
-  -- ^42 ON: full 8th kicks (groove). OFF: sparse intro kick
-  -- Before drop: ghost doubles appear (flam at +0.15 beat)
-  $ midiOn  "^42" (<| "k*8") -- the real NTO groove: 8th kicks
-  $ midiOff "^42" (<| "k ~ ~ <~!3 k>") -- intro: sparse
-  $ sometimesBy "^29" ( -- ^29 mid knob: kick ghost doubles (pre-drop energy)
+d1 $ gF1 $ gMute2 -- KICK: Round sub thud, 8th pulse (att 50ms, no click)
+  -- NTO: kick on every downbeat 8th, gets DEEPER over time
+  -- Ghost doubles before drop. Centroid 1100→200Hz = more sub as track progresses.
+  $ midiOn  "^42" (<| "k*8") -- ON: full 8th pulse (NTO groove)
+  $ midiOff "^42" (<| "k ~ ~ <~!3 k>") -- OFF: sparse intro
+  $ sometimesBy "^29" ( -- ^29: ghost doubles (pre-drop energy)
     superimpose (("0.07" <~) . (|* gain 0.7))
     )
-  $ fix ((# att 0.01) . (# rel 0.5) . (# lpf 2000)) "kick:4"
-  $ "[techno:0,808bd:2,kick:4]"
+  $ "[techno:0,808bd:2]"
+  # att 0.05 -- 50ms attack = round thud, no click
+  # rel 0.2
+  # lpf (slow 64 $ range 800 300 saw) -- gets darker/deeper over time
   # gain 1.3
-d2 $ gF1 $ gM -- CLAP: Dry snap, contretemps (demucs: enters at climax ~200s)
-  -- NTO clap: beats 1&3 (contretemps), ~1200Hz, dry mid+hi_mid snap
-  -- Appears late in arrangement for climax energy
-  $ midiOn "^43" (<| "cp ~ cp ~") -- ON: contretemps (beats 1&3, NTO climax pattern)
-  $ midiOff "^43" (<| "~ cp ~ <~ cp*<1 2>>") -- OFF: classic backbeat (our interpretation)
-  $ sometimesBy "^30" ( -- ^30 mid knob: flam probability
-    superimpose (("e" <~) . (|* gain 0.7))
+d2 $ gF1 $ gM -- CLAP: Dry quiet snap, contretemps (enters late, ~200s)
+  -- NTO clap: peak=0.13 (QUIET!), att=10ms, dec=12ms, dom=1292Hz
+  -- On beats 1&3 (contretemps), dry mid-snap, not a fat backbeat
+  $ midiOn "^43" (<| "cp ~ cp ~") -- ON: contretemps (NTO climax)
+  $ midiOff "^43" (<| "~ cp ~ <~ cp*<1 2>>") -- OFF: backbeat (our touch)
+  $ sometimesBy "^30" ( -- ^30: flam probability
+    superimpose (("e" <~) . (|* gain 0.6))
     )
   $ "h2ogmcp"
-  # room (slow 32 $ range 0.3 0.6 saw)
-  # sz (slow 32 $ range 0.1 0.45 cosine)
-  # dry 1
-  # gain 1.1
+  # hpf 800 -- cut the low end: NTO clap is 0% sub, pure mid
+  # lpf 4000
+  # room 0.1 # dry 1.5 -- very dry
+  # gain 0.7 -- QUIET accent, not a slam (NTO peak=0.13)
   # pan 0.55
-d3 $ gF1 $ gM -- HATS/CY: Open hat 8ths → cymbal morph at drop (demucs confirmed)
-  -- NTO: OH on every upbeat 8th (alternating with kick)
-  -- At drop (~2:20): hats morph to high cymbals, kick drops out
-  -- ^44 ON: cymbal mode (breakdown). OFF: open hat groove
-  -- ^76 push: rolls
-  $ midiOn "^76" (stut 3 0.6 "s") -- push: hat rolls
-  $ midiOn "^44" ( -- state ON: cymbal breakdown (no kick, shimmering)
-    (<| "[~ cy]*4") . (# "h2ogmcy:1") . (# legato 0.6)
+d3 $ gF1 $ gM -- OH/CY: One evolving voice — warm OH → bright shimmer
+  -- NTO: upbeat 8ths that BRIGHTEN over time (centroid 4000→8400Hz)
+  -- Groove: peak=0.55, att=40ms (soft). Breakdown: peak=0.05 (whisper!), att=7ms
+  -- ^44 ON: cymbal shimmer (breakdown mode, quiet). OFF: warm open hat (groove)
+  -- ^76 push: rolls. ^52: legato/tightness. ^32: roll probability
+  $ midiOn "^76" (stut 3 0.6 "s") -- push: rolls
+  $ midiOn "^44" ( -- ON: cymbal shimmer breakdown (quiet, bright, short)
+    (|* gain 0.3) . (# legato 0.15) . (# "h2ogmcy:1") . (# hpf 6000)
     )
-  $ sometimesBy "^32" ( -- ^32 mid knob: roll probability
-    ply "<2!3 [2 4]>"
-    )
-  $ "[~ h]*4" -- base: open hat on every upbeat 8th
+  $ sometimesBy "^32" (ply "<2!3 [2 4]>") -- ^32: roll probability
+  $ "[~ h]*4" -- upbeat 8ths (every upbeat, alternating with kick)
   # "h2ogmhh"
-  # legato (range 0.1 0.8 "^52") -- ^52 bot knob: hat tightness
+  # n "<6!6 [6 8] 8>" -- OH brightening: n6=open → n8=more open over bars
+  # legato (range 0.2 0.9 "^52") -- ^52: tightness
+  # att 0.04 -- 40ms soft onset (NTO OH is not a tick)
   # pan 0.42
-  # n "<6!3 [6 8]>" -- 6=open hat, 8=more open. vary per bar
-  # gain 1.5
+  # gain 1.4
 d4 $ gF2 $ gM3 -- BASS: V chord tones (F2/A2/C2), rhythmically alive
   -- onset analysis: NTO bass = ALWAYS F2/A2/C2 (V chord), never sits on Bb!
   -- hits every ~2 beats with variation, answer at beat 2.7→3.7→next bar 0.2