audio-verification

Audio verification

An audio graph that compiles can still be silent, over-range, noisy, or abruptly cut off. Render it to samples when that will answer the reported problem, then exercise the actual app path for scheduling, lifecycle, and device behavior.

Evidence boundary

Measurements can establish sample-level facts. They do not establish that a cue is pleasant, that a person heard it, or that the browser and output device played it correctly. Report those limits explicitly.

For a changed cue:

1. Render the real graph offline when practical. Prefer importing the production module; if you reproduce the graph in a probe, disclose that it may drift.
2. Measure the fields relevant to the symptom. Compare before and after under identical settings when a meaningful baseline exists.
3. Exercise the cue in the running app when the issue involves user gestures, overlapping voices, scheduling, context state, or device changes.
4. If the evidence cannot settle the complaint, report the result as a bounded measurement or non-reproduction and identify the needed listening check.

Running the included probe

scripts/audio-probe.js is a classic script with no imports. Evaluate it in a browser page using an available browser automation, preview, test runner, or developer-console facility. It defines globalThis.AudioProbe.

const metrics = await AudioProbe.measure((ctx, destination) => {
  const oscillator = ctx.createOscillator();
  const gain = ctx.createGain();
  gain.gain.setValueAtTime(0, 0);
  gain.gain.linearRampToValueAtTime(0.3, 0.02);
  gain.gain.exponentialRampToValueAtTime(0.0004, 0.4);
  oscillator.connect(gain).connect(destination);
  oscillator.start(0);
  oscillator.stop(0.5);
}, { seconds: 0.6 });

const comparison = await AudioProbe.compare(
  { before: buildOld, after: buildNew },
  { seconds: 0.6 },
);

OfflineAudioContext requires a browser-compatible Web Audio implementation. Use what the project or host already provides. Installing a browser engine or a Web Audio shim solely for a small check is optional and should be proportionate to the task.