Source: https://guthlabs.ai/docs/instruments/pan-law-stereo-balance-level-calculator/implementation/

instrument implementation / implementation-contract

# Pan Law / Stereo Balance Level Calculator implementation

A source-bound implementation contract for Pan Law / Stereo Balance Level Calculator; deployment and executable qualification remain separate.

Status: **VERIFIED_CLEAN**Lifecycle: **implementation-contract**

## 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**: t5-106

**Effect**: Computation or source lookup only

## Input and validation requirements

Hard-left and hard-right positions produce a zero linear gain on one channel. Converting that channel to dB requires log10(0), so a finite numeric dB output is undefined; the instrument must explicitly return -Infinity or reject the result. The specification also does not state the pan-position convention or explicitly define the linear-to-dB conversion.

## 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": {
    "pan_position_degrees": 0,
    "pan_law_db": -3
  },
  "expected_outputs": {
    "left_gain_linear": 0.70794578,
    "right_gain_linear": 0,
    "left_gain_db": -3,
    "right_gain_db": "-Infinity"
  },
  "working": "panLawGain=10^(-3/20)=10^(-0.15)=0.70794578. theta=0°. L=cos(0°)*0.70794578=1*0.70794578=0.70794578. R=sin(0°)*0.70794578=0*0.70794578=0. 20*log10(0.70794578)=-3 dB. 20*log10(0)=-Infinity dB."
}
````

## Other records

[01**Overview**](<https://guthlabs.ai/docs/instruments/pan-law-stereo-balance-level-calculator/>)[02**Mechanism**](<https://guthlabs.ai/docs/instruments/pan-law-stereo-balance-level-calculator/mechanism/>)[04**Qualification**](<https://guthlabs.ai/docs/instruments/pan-law-stereo-balance-level-calculator/qualification/>)

## Sources and evidence

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

- `VERIFIED_LEDGER.json`

- `evidence-tranche5/tranche5-results.json`