Source: https://guthlabs.ai/docs/instruments/speaker-impedance-load-calculator-series-parallel/implementation/

instrument implementation / implementation-contract

# Speaker Impedance Load Calculator (Series/Parallel) implementation

A source-bound implementation contract for Speaker Impedance Load Calculator (Series/Parallel); 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**: t2-025

**Effect**: Computation or source lookup only

## Input and validation requirements

A parallel input containing a zero-ohm speaker reaches 1/0 and must be rejected, but the specification does not state an input-validation rule. The minimum amplifier rating warning is also not computable because no amplifier rating or safe-loading threshold is supplied.

## 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": {
    "wiring_topology": "series",
    "speaker_impedances": [
      {
        "value": 8,
        "unit": "ohm"
      },
      {
        "value": 8,
        "unit": "ohm"
      },
      {
        "value": 4,
        "unit": "ohm"
      }
    ]
  },
  "expected_outputs": {
    "total_load_ohms": 20,
    "min_amp_rating_warning": "UNDEFINED: no amplifier minimum-load/rating input or warning criterion"
  },
  "working": "Series: Ztot = 8 ohm + 8 ohm + 4 ohm = 16 ohm + 4 ohm = 20 ohm. The amp warning cannot be computed because no amplifier constraint is provided."
}
````

## Other records

[01**Overview**](<https://guthlabs.ai/docs/instruments/speaker-impedance-load-calculator-series-parallel/>)[02**Mechanism**](<https://guthlabs.ai/docs/instruments/speaker-impedance-load-calculator-series-parallel/mechanism/>)[04**Qualification**](<https://guthlabs.ai/docs/instruments/speaker-impedance-load-calculator-series-parallel/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-tranche2/tranche2-results.json`