@audio/synth-modal

Modal synthesis — impulse-invariant resonator bank; F&R-cited bar/membrane/plate/tube/stiff-string tables, strike-position weighting, per-mode T60

npm install @audio/synth-modal

import modal from '@audio/synth-modal'

A bank of impulse-invariant two-pole resonators, one per vibrational mode, excited by an impulse or short noise burst (Adrien 1991, "The missing link: modal synthesis"; Cook, Real Sound Synthesis for Interactive Applications, ch. 5). Mode-ratio tables per model are cited from Fletcher & Rossing, The Physics of Musical Instruments, 2nd ed. — string (Fletcher 1964 stiff-string), bar (free-free Euler-Bernoulli), membrane (Bessel-zero circular membrane), plate (free circular plate), tube-open/tube-closed (pipe harmonics/odd-harmonics).

modal(220, { model: 'string', inharmonicity: 0.0002, strike: 0.3 })

| Param | Default | | |---|---|---| | freq | — | Fundamental (mode 1) Hz (positional) | | model | 'bar' | 'string' | 'bar' | 'membrane' | 'plate' | 'tube-open' | 'tube-closed' | | modes | — | Custom [{ratio, gain?, t60?}] — overrides model/nmodes/inharmonicity | | nmodes | 8 | Modes drawn from the model's table | | t60 | 2 | Fundamental decay time, seconds (-60dB) | | damping | 0.7 | HF loss exponent: t60_k = t60·(f1/fk)^damping | | inharmonicity | 0 | String-only stiffness coefficient B: fk = k·f1·√(1+B·k²) | | strike | 0.5 | 0..1 strike/pluck position (1D models only) | | exciter | 'impulse' | 'impulse' | 'noise' | custom Float32Array | | duration | — | Default: covers the slowest mode's T60 | | amp | 0.8 | Peak amplitude | | seed | 9 | Noise-exciter PRNG seed | | fs | 44100 | Sample rate |

Use when: physically-grounded percussive/struck timbres (bars, membranes, plates, strings, tubes) with per-model literature-sourced mode ratios rather than hand-tuned partials.

Part of @audio/synth — the synth family umbrella.

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