Struct SpringModel 

pub struct SpringModel {
    pub num_springs: usize,
    pub transit_ms: [f64; 6],
    pub fc_hz: f64,
    pub rt60_s: f64,
    pub num_allpasses: usize,
    pub ap_coeff: f64,
    pub damping_fc_hz: f64,
    pub hf_chirp_gain: f64,
}

Named spring-tank model parameters (Accutronics / RE-201 grounded).

Transit times, fC and RT60 are partly inferred (the primary datasheet tables were 403-blocked at authoring time — flagged [A] in the example provenance) and chosen from the published-class ranges in the design doc.

Fields

num_springs: usize

Number of spring lines summed at the output.

transit_ms: [f64; 6]

Per-spring transit time (ms) — the loop delay Td of each line. Slightly detuned across springs to decorrelate. num_springs entries are used.

fc_hz: f64

Dispersion transition frequency fC (Hz): group delay disperses below it.

rt60_s: f64

Reverberation time RT60 (s) — sets the loop feedback gain.

num_allpasses: usize

Number of stretched allpasses per spring (dispersion strength ∝ M·K). The JAES reference uses M=100; we ship 32 (≈11 ms group-delay dispersion across 300 Hz–2.4 kHz, a clear spring chirp) to hold a comfortable realtime margin (≥30x release — fidelity/cost OQ3).

ap_coeff: f64

Stretched-allpass coefficient a (≈0.75 per JAES).

damping_fc_hz: f64

Default damping-LPF cutoff (Hz) — how fast the tail darkens.

hf_chirp_gain: f64

Reserved: HF-chirp cascade gain (OFF / 0.0 in v1 — OQ3, not hot path).

Implementations

impl SpringModel

pub fn type4() -> SpringModel

Accutronics Type 4 — 17“ tank, Fender standard, long decay. transit ~33/37.5 ms [A], fC 4200 Hz, RT60 2.85 s.

pub fn type8() -> SpringModel

Accutronics Type 8 — 9.25“ short tank, 3 springs, shorter decay. transit ~30/32/34 ms [A], fC 3500 Hz, RT60 1.8 s.

pub fn type9() -> SpringModel

Accutronics Type 9 — 17“, 6-spring (3 coupled pairs), densest. transit ~33/36.5/40 ms [A], fC 4000 Hz, RT60 2.5 s.

pub fn re201_tank() -> SpringModel

Roland RE-201 tank — small dark 2-spring tank, fast “boing”. transit ~31/35 ms [A], fC 3000 Hz, RT60 1.6 s.

Trait Implementations

impl Clone for SpringModel

fn clone(&self) -> SpringModel

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for SpringModel

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.