nx_squeaker.nx

nx_squeaker.nx -- THE TOY. A dog-toy ball that makes its noise because a dog's jaw compresses it. Operator 2026-07-25: "a dog toy ball that is designed to make the noise when compressed by a dog's mouth". This is the physical model of that object, from the bite down: jaw force -> shell compression -> air displaced -> chamber pressure -> reed valve flutters -> flow through the neck -> radiated sound Every stage is a real physical quantity in manufacturable units (newtons, millimetres, cubic millimetres), because the whole point of rung R5 is to INVERT this model and hand back a geometry somebody can actually mould. A model in arbitrary units cannot produce a spec. WHY THE PITCH GLIDES, AND WHY THAT IS THE PRODUCT. The chamber is a Helmholtz resonator: w = c * sqrt(A_neck / (V_chamber * L_neck)) A dog's bite REMOVES volume from the chamber, and w rises as V falls. So the sound a dog produces by biting is not a fixed beep -- it is a rising squeal whose contour is drawn by the dog's own jaw. Prey distress calls rise in pitch too. That correspondence is the reason this object can sound like something worth catching instead of like a rubber toy, and it is measurable: the gate checks that a harder bite raises the pitch and that a bigger chamber lowers it, both in the direction the physics demands rather than the direction I would like. THE REED IS THE SAME PHYSICS AS A VOCAL FOLD. A squeaker tongue and a larynx are both elastic valves driven unstably by the flow past them, so this organ does not implement a second oscillator: it drives nx_vox_source with the chamber pressure and takes its flow back. That reuse is not just DRY, it is why the toy inherits nonlinear regimes -- the roughness, the pitch breaks and the cycle-to-cycle variation that stop a dog habituating -- from a model already gated at 13/13. Integer fixed-point, deterministic. license_tier: ORIGINAL expect_exit: 0