Microphone Polar Pattern / Proximity Effect Reference implementation

Binding contract

This record describes what an executable surface must bind and validate. It does not claim that a public calculator, package, or production route is deployed.

Record owner

Guth Instruments

Lifecycle

verified-clean

Evidence ID

t6-063

Effect

Computation or source lookup only

Input and validation requirements

A very large JSON angle such as 1e309 becomes Infinity in JavaScript, causing Math.cos(Infinity) to return NaN for cardioid and figure-8. The instrument should reject non-finite angles but may instead render undefined or corrupted plot data. The unspecified angle unit also permits materially different sensitivity values.

Required corrections

No binding erratum is attached to this unique-name record. Implementers must still preserve the declared units, domain, and failure behavior.

Inspectable interface fixture

The sample below is evidence for interface and validation tests, not a production implementation.

{
  "inputs": {
    "pattern": "cardioid",
    "angle_deg": [
      0,
      90,
      180
    ]
  },
  "expected_outputs": {
    "sampled_points": [
      {
        "angle_deg": 0,
        "relative_sensitivity": 1
      },
      {
        "angle_deg": 90,
        "relative_sensitivity": 0.5
      },
      {
        "angle_deg": 180,
        "relative_sensitivity": 0
      }
    ],
    "key_curve_features": {
      "maximum": {
        "angle_deg": 0,
        "value": 1
      },
      "rear_null": {
        "angle_deg": 180,
        "value": 0
      },
      "range": [
        0,
        1
      ]
    }
  },
  "working": "theta=0 degrees=0 radians: cos(0)=1; sensitivity=0.5+0.5*1=1.000000. theta=90 degrees=pi/2 radians: cos(pi/2)=0; sensitivity=0.5+0.5*0=0.500000. theta=180 degrees=pi radians: cos(pi)=-1; sensitivity=0.5+0.5*(-1)=0.000000. The cardioid maximum is at 0 degrees and the rear null is at 180 degrees."
}

Other records

Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

• VERIFIED_LEDGER.json
• evidence-tranche6/tranche6-results.json