{
  "schemaVersion": 3,
  "cityId": "deep-tide",
  "seed": "deep-tide-pressure-choir-001",
  "title": "Pressure Choir",
  "sourceWorld": {
    "worldId": "deep-tide",
    "hook": "A cultivated shell civilization on a dark thermal shelf.",
    "story": "Shared pressure passages carry low resonances between homes; sparse glass signals cross the open swimming lanes while distant calls answer above the vents."
  },
  "intent": {
    "oneLine": "A slow six-beat pressure cycle joins distant synthetic calls, submerged glass pings and restrained bronze maintenance rhythms.",
    "keywords": [
      "abyssal",
      "pressure-shell",
      "listening",
      "thermal",
      "cultivated-light"
    ],
    "avoid": [
      "literal whale or bubble recordings unavailable in the engine",
      "bright arcade percussion",
      "constant melody",
      "triumphant fantasy chords",
      "busy hi-hats"
    ]
  },
  "musicalIdentity": {
    "bpm": 48,
    "swing": 0,
    "rootMidi": 38,
    "scale": "minor-pentatonic",
    "signatureMotif": [
      0,
      3,
      2,
      -1
    ],
    "progression": [
      0,
      -1,
      2,
      0
    ],
    "phraseBars": 8
  },
  "worldFingerprint": {
    "meter": "6/8",
    "timingBehavior": "tidal",
    "material": "glass-water",
    "spatialShape": "vertical-echo",
    "arrangementBehavior": "call-response",
    "register": "low",
    "silence": 0.65
  },
  "samplePalette": [
    {
      "material": "glass",
      "intensities": [
        "light"
      ]
    },
    {
      "material": "metal",
      "intensities": [
        "medium"
      ]
    },
    {
      "material": "soft",
      "intensities": [
        "heavy"
      ]
    }
  ],
  "soundEffects": {
    "building.place": {
      "label": "Shell seated",
      "description": "A restrained bronze contact marks a new pressure coupling.",
      "sample": {
        "material": "metal",
        "intensity": "medium"
      },
      "gain": 0.32
    },
    "building.remove": {
      "label": "Collar released",
      "description": "A muted soft impact suggests the release of a fitted shell segment.",
      "sample": {
        "material": "soft",
        "intensity": "heavy"
      },
      "gain": 0.27
    },
    "placement.invalid": {
      "label": "Seal unavailable",
      "description": "A quiet glass tick accompanies the invalid-placement indication.",
      "sample": {
        "material": "glass",
        "intensity": "light"
      },
      "gain": 0.13
    }
  },
  "spatialMix": {
    "nature": {
      "label": "Open abyss",
      "description": "Long low synth tones suggest remote animal calls, haze chords suggest pressure groans, and sparse glass tones suggest sonar and rising vent droplets; these are synthesized impressions, not field recordings.",
      "keywords": [
        "distant-calls",
        "space",
        "pressure"
      ],
      "lead": "glass",
      "bass": "sub",
      "pad": "haze",
      "drums": "dust",
      "texture": "air",
      "brightness": 0.18,
      "space": 0.93,
      "grit": 0.08,
      "density": 0.12
    },
    "city": {
      "label": "Inhabited shells",
      "description": "The same motif becomes a sparse glass signal above a deterministic six-eighth-note pump cycle, low bass and occasional recorded bronze-like impacts.",
      "keywords": [
        "couplings",
        "communal",
        "pump-cycle"
      ],
      "lead": "bell",
      "bass": "sub",
      "pad": "organ",
      "drums": "metal",
      "texture": "machinery",
      "brightness": 0.28,
      "space": 0.72,
      "grit": 0.16,
      "density": 0.29
    },
    "transition": {
      "curve": "equal-power",
      "description": "Both layers share the eight-bar harmonic tide and four-note call; moving into the settlement reveals a measured pump rhythm while the open-water calls recede."
    }
  }
}