{
  "_topology": {
    "architecture": "cascaded mixed-order Linkwitz-Riley split tree with shared high-pass carryover (LR4 / LR4 / LR4)",
    "diagram": "Input\n  +-- LR4 HP 70 Hz (2 biquads, global boundary)\n    +-- LR4 split @ 200 Hz\n        +-- LR4 LP 200 Hz (2 biquads) -> L26RO4Y\n        +-- LR4 HP 200 Hz (2 biquads) -> next split\n      +-- LR4 split @ 800 Hz\n          +-- LR4 LP 800 Hz (2 biquads) -> L22MG (nude)\n          +-- LR4 HP 800 Hz (2 biquads) -> next split\n        +-- LR4 split @ 2500 Hz\n            +-- LR4 LP 2500 Hz (2 biquads) -> GRS PT6816\n            +-- LR4 HP 2500 Hz (2 biquads) -> ND25FW4 (nude 18mm)",
    "stages": [
      {
        "stage": 1,
        "driver": "L26RO4Y",
        "passband_hz": [
          70.0,
          200.0
        ],
        "global_boundary_hp_biquads": 2,
        "inherited_upstream_hp_biquads": 0,
        "own_branch_hp_biquads": 0,
        "own_branch_lp_biquads": 2,
        "effective_crossover_biquads": 4,
        "effective_lr4_biquads": 4,
        "flat_eq_biquads": 2,
        "effective_total_biquads": 6,
        "polarity": 1
      },
      {
        "stage": 2,
        "driver": "L22MG (nude)",
        "passband_hz": [
          200.0,
          800.0
        ],
        "global_boundary_hp_biquads": 2,
        "inherited_upstream_hp_biquads": 0,
        "own_branch_hp_biquads": 2,
        "own_branch_lp_biquads": 2,
        "effective_crossover_biquads": 6,
        "effective_lr4_biquads": 6,
        "flat_eq_biquads": 3,
        "effective_total_biquads": 9,
        "polarity": 1
      },
      {
        "stage": 3,
        "driver": "GRS PT6816",
        "passband_hz": [
          800.0,
          2500.0
        ],
        "global_boundary_hp_biquads": 2,
        "inherited_upstream_hp_biquads": 2,
        "own_branch_hp_biquads": 2,
        "own_branch_lp_biquads": 2,
        "effective_crossover_biquads": 8,
        "effective_lr4_biquads": 8,
        "flat_eq_biquads": 1,
        "effective_total_biquads": 9,
        "polarity": 1
      },
      {
        "stage": 4,
        "driver": "ND25FW4 (nude 18mm)",
        "passband_hz": [
          2500.0,
          20000.0
        ],
        "global_boundary_hp_biquads": 2,
        "inherited_upstream_hp_biquads": 4,
        "own_branch_hp_biquads": 2,
        "own_branch_lp_biquads": 0,
        "effective_crossover_biquads": 8,
        "effective_lr4_biquads": 8,
        "flat_eq_biquads": 6,
        "effective_total_biquads": 14,
        "polarity": 1
      }
    ],
    "summary": {
      "xover_types": [
        "LR4",
        "LR4",
        "LR4"
      ],
      "xover_orders": [
        4,
        4,
        4
      ],
      "shared_tree_crossover_biquads": 14,
      "standalone_channel_crossover_biquads": 26,
      "shared_tree_lr4_biquads": 14,
      "standalone_channel_lr4_biquads": 26,
      "flat_eq_biquads": 12,
      "shared_tree_total_biquads_with_eq": 26,
      "standalone_channel_total_biquads": 38,
      "max_biquads_per_driver_limit": 15,
      "max_effective_total_biquads_per_driver": 14,
      "per_driver_limit_met": true
    },
    "notes": [
      "Shared-tree count assumes the DSP can route a high-pass bus into the next split stage.",
      "Standalone-channel count is what is exported per driver when each output channel must contain all inherited upstream filters.",
      "LR2 splits use one Q=0.5 biquad per edge and invert the next/downstream branch; LR4 splits use two Q=0.7071 biquads per edge without a required polarity inversion.",
      "Flat-EQ is capped after crossover filters so every exported driver channel stays at or below 15 total biquads.",
      "Gain, delay, and polarity are not counted as biquads."
    ]
  },
  "_drivers": [
    "L26RO4Y",
    "L22MG (nude)",
    "GRS PT6816",
    "ND25FW4 (nude 18mm)"
  ],
  "drivers": {
    "L26RO4Y": {
      "gain_db": -13.295,
      "delay_ms": 0.0,
      "polarity": 1,
      "filters": [
        {
          "type": "highpass",
          "fc_hz": 70.0,
          "q": 0.7071,
          "gain_db": 0.0,
          "source": "LR4 global boundary high-pass"
        },
        {
          "type": "highpass",
          "fc_hz": 70.0,
          "q": 0.7071,
          "gain_db": 0.0,
          "source": "LR4 global boundary high-pass"
        },
        {
          "type": "lowpass",
          "fc_hz": 200.0,
          "q": 0.7071,
          "gain_db": 0.0,
          "source": "LR4 branch low-pass"
        },
        {
          "type": "lowpass",
          "fc_hz": 200.0,
          "q": 0.7071,
          "gain_db": 0.0,
          "source": "LR4 branch low-pass"
        },
        {
          "type": "peaking",
          "fc_hz": 110.0,
          "q": 1.0,
          "gain_db": -1.2,
          "source": "flat-EQ"
        },
        {
          "type": "lowshelf",
          "fc_hz": 95.0,
          "q": 1.0,
          "gain_db": -0.534,
          "source": "flat-EQ"
        }
      ]
    },
    "L22MG (nude)": {
      "gain_db": 12.533,
      "delay_ms": -0.48,
      "polarity": 1,
      "filters": [
        {
          "type": "highpass",
          "fc_hz": 70.0,
          "q": 0.7071,
          "gain_db": 0.0,
          "source": "LR4 global boundary high-pass"
        },
        {
          "type": "highpass",
          "fc_hz": 70.0,
          "q": 0.7071,
          "gain_db": 0.0,
          "source": "LR4 global boundary high-pass"
        },
        {
          "type": "highpass",
          "fc_hz": 200.0,
          "q": 0.7071,
          "gain_db": 0.0,
          "source": "LR4 branch high-pass"
        },
        {
          "type": "highpass",
          "fc_hz": 200.0,
          "q": 0.7071,
          "gain_db": 0.0,
          "source": "LR4 branch high-pass"
        },
        {
          "type": "lowpass",
          "fc_hz": 800.0,
          "q": 0.7071,
          "gain_db": 0.0,
          "source": "LR4 branch low-pass"
        },
        {
          "type": "lowpass",
          "fc_hz": 800.0,
          "q": 0.7071,
          "gain_db": 0.0,
          "source": "LR4 branch low-pass"
        },
        {
          "type": "peaking",
          "fc_hz": 500.0,
          "q": 1.0,
          "gain_db": -4.535,
          "source": "flat-EQ"
        },
        {
          "type": "peaking",
          "fc_hz": 330.0,
          "q": 1.0,
          "gain_db": 3.239,
          "source": "flat-EQ"
        },
        {
          "type": "peaking",
          "fc_hz": 620.0,
          "q": 1.0,
          "gain_db": -0.497,
          "source": "flat-EQ"
        }
      ]
    },
    "GRS PT6816": {
      "gain_db": 4.024,
      "delay_ms": 0.025,
      "polarity": 1,
      "filters": [
        {
          "type": "highpass",
          "fc_hz": 70.0,
          "q": 0.7071,
          "gain_db": 0.0,
          "source": "LR4 global boundary high-pass"
        },
        {
          "type": "highpass",
          "fc_hz": 70.0,
          "q": 0.7071,
          "gain_db": 0.0,
          "source": "LR4 global boundary high-pass"
        },
        {
          "type": "highpass",
          "fc_hz": 200.0,
          "q": 0.7071,
          "gain_db": 0.0,
          "source": "LR4 cascaded upstream high-pass"
        },
        {
          "type": "highpass",
          "fc_hz": 200.0,
          "q": 0.7071,
          "gain_db": 0.0,
          "source": "LR4 cascaded upstream high-pass"
        },
        {
          "type": "highpass",
          "fc_hz": 800.0,
          "q": 0.7071,
          "gain_db": 0.0,
          "source": "LR4 branch high-pass"
        },
        {
          "type": "highpass",
          "fc_hz": 800.0,
          "q": 0.7071,
          "gain_db": 0.0,
          "source": "LR4 branch high-pass"
        },
        {
          "type": "lowpass",
          "fc_hz": 2500.0,
          "q": 0.7071,
          "gain_db": 0.0,
          "source": "LR4 branch low-pass"
        },
        {
          "type": "lowpass",
          "fc_hz": 2500.0,
          "q": 0.7071,
          "gain_db": 0.0,
          "source": "LR4 branch low-pass"
        },
        {
          "type": "peaking",
          "fc_hz": 2800.0,
          "q": 1.0,
          "gain_db": -0.373,
          "source": "flat-EQ"
        }
      ]
    },
    "ND25FW4 (nude 18mm)": {
      "gain_db": 1.16,
      "delay_ms": -0.125,
      "polarity": 1,
      "filters": [
        {
          "type": "highpass",
          "fc_hz": 70.0,
          "q": 0.7071,
          "gain_db": 0.0,
          "source": "LR4 global boundary high-pass"
        },
        {
          "type": "highpass",
          "fc_hz": 70.0,
          "q": 0.7071,
          "gain_db": 0.0,
          "source": "LR4 global boundary high-pass"
        },
        {
          "type": "highpass",
          "fc_hz": 200.0,
          "q": 0.7071,
          "gain_db": 0.0,
          "source": "LR4 cascaded upstream high-pass"
        },
        {
          "type": "highpass",
          "fc_hz": 200.0,
          "q": 0.7071,
          "gain_db": 0.0,
          "source": "LR4 cascaded upstream high-pass"
        },
        {
          "type": "highpass",
          "fc_hz": 800.0,
          "q": 0.7071,
          "gain_db": 0.0,
          "source": "LR4 cascaded upstream high-pass"
        },
        {
          "type": "highpass",
          "fc_hz": 800.0,
          "q": 0.7071,
          "gain_db": 0.0,
          "source": "LR4 cascaded upstream high-pass"
        },
        {
          "type": "highpass",
          "fc_hz": 2500.0,
          "q": 0.7071,
          "gain_db": 0.0,
          "source": "LR4 branch high-pass"
        },
        {
          "type": "highpass",
          "fc_hz": 2500.0,
          "q": 0.7071,
          "gain_db": 0.0,
          "source": "LR4 branch high-pass"
        },
        {
          "type": "highshelf",
          "fc_hz": 18000.0,
          "q": 1.0,
          "gain_db": 8.0,
          "source": "flat-EQ"
        },
        {
          "type": "peaking",
          "fc_hz": 10000.0,
          "q": 2.0,
          "gain_db": 6.31,
          "source": "flat-EQ"
        },
        {
          "type": "peaking",
          "fc_hz": 12000.0,
          "q": 1.0,
          "gain_db": -4.59,
          "source": "flat-EQ"
        },
        {
          "type": "peaking",
          "fc_hz": 16500.0,
          "q": 1.0,
          "gain_db": 3.83,
          "source": "flat-EQ"
        },
        {
          "type": "peaking",
          "fc_hz": 9000.0,
          "q": 2.0,
          "gain_db": -3.108,
          "source": "flat-EQ"
        },
        {
          "type": "peaking",
          "fc_hz": 14000.0,
          "q": 1.0,
          "gain_db": -1.31,
          "source": "flat-EQ"
        }
      ]
    }
  }
}