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Musical Arc

Team Onyx — "La Última Jugada"

Step 2 — Musical Arc

Film: “La Ultima Jugada”
Defined by: onyx-editor (Post-Production Lead)
Date: 2026-05-22
Status: DRAFT — stem plan confirmed w/ techlead. Will finalize stem boundaries against scene_list.md when available.


Overview

The score has one job: follow the narrator’s emotional register, never lead it. The music reacts to the story — it never telegraphs what’s coming. This is the single most important mixing rule.

The score spans the full runtime as a continuous emotional thread, but it is NOT wall-to-wall. It breathes. It thins. It disappears entirely at key moments so that silence — or the ambient courtyard sounds — can carry the emotional weight.


Instrumentation Palette

InstrumentRoleWhen
Acoustic guitar (nylon string)Primary melodic voice. Warm, intimate, unhurried.Throughout — but density varies by act
MarimbaRhythmic warmth. The “Sunday afternoon” feeling.Acts I-II only. Drops out in Act III.
Light percussion (cajon, shaker)Subtle pulse. The metronomic heartbeat under the ritual.Acts I-II. Fades in late Act II. Gone in Act III.
SilenceThe most powerful instrument in Act III.Hidden card reveals, key emotional beats

Prohibited: No synthesizers. No orchestral swells. No string sections. No piano. No drums beyond light cajon/shaker. No dissonant stingers, drone tones, or heartbeat bass drops (per design brief sound prohibitions).


The Arc: Five Movements

The score operates in five continuous movements that map to the narrative structure. These are not discrete music cues — they flow into each other, with instrumentation and energy shifting organically.

Movement 1: “The Ritual” (Act I — warm memories)

Est. duration: 60-90s
Character: Gentle, rhythmic, sun-baked. A Sunday afternoon. The music breathes with the card-dealing rhythm — not literally synced to card flips, but inhabiting the same unhurried tempo.
Instrumentation: Guitar (fingerpicked, warm), marimba (soft, rhythmic pattern), shaker (barely there).
Dynamic: pp to mp. Never louder than the narrator.
Key: Major. Warm. Think D major or G major — open guitar keys.
Lyria prompt direction: “gentle acoustic guitar fingerpicking, soft marimba, warm Sunday afternoon, Mexican folk, intimate, unhurried, nylon string, no drums, no bass, no synthesizer”

Movement 2: “The Deepening” (Act II — richer memories, the game’s meaning)

Est. duration: 45-60s
Character: Fuller, more layered. The marimba becomes more melodic (not just rhythmic). The guitar adds a second voice — gentle counterpoint. The music is warmer, richer, like the light intensifying.
Instrumentation: Guitar (two voices — melody and accompaniment), marimba (melodic now), cajon (soft pattern).
Dynamic: mp. Slightly more present, but still under the narrator.
Key: Same key center, but with more harmonic color. Add the IV and vi chords.
Lyria prompt direction: “warm acoustic guitar duet, melodic marimba, light cajon, Mexican folk, intimate family gathering, building gently, nylon string, no drums, no synthesizer”

Movement 3: “The Silence” (Rosario’s death, transition to Act III)

Est. duration: 15-20s
Character: The music stops. Not a dramatic cut — a fade. The instruments thin one by one: percussion first, then marimba, then guitar sustaining a single note that decays into silence. The ambient soundscape (courtyard, birds, wind) fills the space.
Instrumentation: Guitar sustain → nothing. Veo ambient audio carries the moment.
Dynamic: mp → silence.
Lyria prompt direction: This may not need a Lyria stem — could be achieved by fading Movement 2’s tail. If generated: “single guitar note, sustained, fading to silence, ending, breath”

Movement 4: “The Weight” (Act III — three hidden cards)

Est. duration: 60-90s
Character: Spare. A single guitar. No marimba, no percussion. The guitar plays a simple, aching figure — two or three notes, repeated with variation. Minor key. The music is present but stripped bare. It aches AFTER the narrator tells us why.
Sub-movements across the three cards:

CardMusical TreatmentDynamic
La Sirena (unsettling)Guitar enters hesitantly after the reveal. A tentative minor figure.pp — barely there
El Corazon (painful)Guitar repeats the figure, lower register. Slower. A slight tremolo.pp — aching
La Mano (devastating)Guitar plays one note. Holds it. Then silence. The ambient kitchen sounds carry the moment — clock ticking, the quiet of an empty house.ppp → silence

Lyria prompt direction: “solo acoustic guitar, minor key, sparse, aching, single notes, Mexican, sorrowful, intimate, no percussion, no marimba, no other instruments, breath between notes”

Movement 5: “The Return” (Coda — Clara alone, El Sol again)

Est. duration: 15-20s
Character: The guitar returns to the Act I figure — the same fingerpicked pattern, the same key. But it’s solo now. No marimba, no percussion. Just the guitar, echoing the warmth of the ritual from a place of quiet knowing. The music says: the game is over, the warmth remains, life continues.
Instrumentation: Solo guitar. The same melody as Movement 1, but played once, simply, without repetition.
Dynamic: p → fade.
Lyria prompt direction: “solo nylon string guitar, gentle fingerpicking, warm, bittersweet, returning melody, Mexican folk, intimate, fading gently, no other instruments”

Final beat: The guitar fades. Hold 3+ seconds of silence (courtyard ambient only) on the final image before fade-to-black.


Ducking & Mix Strategy

TrackBase volume_dbDucking
VO-NARRATOR+3 to +5 dB— (highest priority, never ducked)
SCORE-3 to -5 dBduck_under: ["VO-NARRATOR"], duck_db: -18 minimum
V1 (Veo ambient)-8 dBNot actively ducked — low enough to sit as a bed

The narrator is always clearly audible over the score. The score supports but never competes. The V-track ambient provides the lived-in soundscape underneath everything.


Score Stem Count (Lyria Generation Plan) — CONFIRMED w/ Tech Lead

3 Lyria stems (confirmed with onyx-techlead 2026-05-22):

StemModelCoverageDurationKey/Tempo
SCORE-WARMLyria 3 ProMovements 1-2 (Acts I-II). Movement 3 achieved by fading this stem’s tail — no separate generation needed.~150sD major, 80 BPM
SCORE-ACHELyria 3 ProMovement 4 (Act III hidden cards). Solo guitar, minor key, spare. Intentionally different from SCORE-WARM — the narrative silence at Rosario’s death makes this transition invisible to the audience.~150sD minor, 80 BPM
SCORE-RETURNLyria 3 ClipMovement 5 (Coda). Solo guitar, warm callback to Movement 1 melody. Must match SCORE-WARM’s BPM and key center so the callback feels like a return.~30sD major, 80 BPM

Why 3 stems, not 4: Movement 3 (The Silence) is achieved by fading SCORE-WARM’s tail to nothing. The silence at Rosario’s death is a deliberate musical absence — generating a separate stem for it wastes a Lyria call and risks introducing an audible seam.

Tempo/key lock: All stems share 80 BPM and a D major/minor tonal center. This ensures the SCORE-RETURN callback melody feels like a genuine return to Movement 1, not a non-sequitur.

Total score duration: ~210-280s across a 3:30-5:00 film. The score is NOT continuous — gaps of silence are intentional and critical, especially at Movement 3 (Rosario’s death) and between hidden card reveals in Movement 4.


Notes to Team

To onyx-techlead: I’ll need Lyria to produce 3-4 stems with very different energy levels but consistent instrumentation (nylon-string guitar is the through-line). The warm stems (Movements 1-2) should feel like a single continuous piece. The Act III stem needs to be radically spare — solo guitar, minor key, with natural gaps/silences built in. Please flag if Lyria can handle this level of dynamic contrast within the same instrumental palette.

To onyx-idea: When writing the scene list, please annotate which shots are “score-silent” (where I should pull the music entirely and let ambient carry). I expect these at: Rosario’s death beat, the pause before each hidden card turn, and the final 3+ seconds before fade-to-black.


Musical arc defined. Will finalize stem boundaries against scene_list.md when available. Mathematical Pacing Review pending scene list.