dB SPL / dBu / dBV Converter 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

t2-001

Effect

Computation or source lookup only

Input and validation requirements

The zero linear-ratio input produces an undefined logarithm and must be rejected. The instrument also has a convention-sensitive ratio direction and requires explicit source-scale branching to avoid confusing dBu with dBV.

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": {
    "source_scale": "SPL",
    "source_value_db": 94,
    "target_scale": "linear_pressure_ratio",
    "reference_pressure_Pa": 0.00002
  },
  "expected_outputs": {
    "pressure_ratio_to_p0": 50118.72336272725,
    "pressure_Pa": 1.002374467254545
  },
  "working": "SPL = 20log10(p/p0). Therefore p/p0 = 10^(94/20) = 10^4.7 = 50118.72336272725. Then p = 50118.72336272725 × 0.000020 Pa = 1.002374467254545 Pa."
}

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-tranche2/tranche2-results.json