Source: https://guthlabs.ai/docs/instruments/delay-time-from-bpm-musical-note-divisions/implementation/

instrument implementation / implementation-contract

# Delay Time from BPM (Musical Note Divisions) implementation

A source-bound implementation contract for Delay Time from BPM (Musical Note Divisions); 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**: t3-001

**Effect**: Computation or source lookup only

## Input and validation requirements

BPM=0 produces an undefined delay through division by zero and must be rejected. Negative BPM also exposes an unstated sign convention: direct arithmetic returns a physically invalid negative delay, while magnitude-based handling returns a positive delay.

## 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": {
    "BPM": 120,
    "note_division": "1/4"
  },
  "expected_outputs": {
    "delay_ms": 500,
    "modulation_rate_hz": 2
  },
  "working": "Quarter note = 60000 / 120 = 500 ms. A 1/4 note is the quarter note, so delay = 500 ms. Convert to frequency: Hz = 1000 / 500 = 2 Hz."
}
````

## Other records

[01**Overview**](<https://guthlabs.ai/docs/instruments/delay-time-from-bpm-musical-note-divisions/>)[02**Mechanism**](<https://guthlabs.ai/docs/instruments/delay-time-from-bpm-musical-note-divisions/mechanism/>)[04**Qualification**](<https://guthlabs.ai/docs/instruments/delay-time-from-bpm-musical-note-divisions/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-tranche3/tranche3-results.json`