feedBack/tests/plugins/tuner/fixtures/audio/real

Real-Instrument WAV Fixtures

Drop WAV recordings from your actual instruments here and they will be picked up automatically by the real-instrument test suite (tests/js/yin.realinstrument.test.js).

Naming Convention

<NoteClass><Octave>_<FreqHz>Hz[_label].wav

An optional label suffix (e.g. _8string, _guitar, _take2) can be added between Hz and .wav — it is ignored by the test runner.

Examples:

File	Note	Expected frequency
E2_82.41Hz.wav	E2	82.41 Hz
E2_82.41Hz_8string.wav	E2	82.41 Hz
A2_110Hz_bass.wav	A2	110.00 Hz
A#3_233.08Hz.wav	A#3	233.08 Hz
D3_146.83Hz.wav	D3	146.83 Hz

The test asserts that YIN detects a frequency within ±20 cents of the value in the filename.

Recording Guidelines

1. Capture the sustain portion — not the attack or release. A 1–2 second clip of a note ringing cleanly is ideal. The test extracts a 4096-sample window from the middle of the file to skip transients.
2. Length — aim for ≤ 2 seconds to keep repository size small.
3. Format — 16-bit PCM WAV (mono or stereo). Export at 44100 Hz or 48000 Hz from your DAW or audio interface.
   • 32-bit float WAV is not supported by the parser — convert to 16-bit PCM first.
4. Channels — mono or stereo both work. Stereo files are averaged to mono before detection.
5. Tune first — play the note in tune against a reference tuner before recording. The file name encodes the expected frequency; a note recorded sharp or flat will fail the test.

Frequency Reference (standard MIDI A4 = 440 Hz)

Note	Hz
E2	82.41
A2	110.00
D3	146.83
G3	196.00
B3	246.94
E4	329.63
A4	440.00
A#3 / Bb3	233.08

For any other note: f = 440 * 2^((midi - 69) / 12).

Committing Recordings

These WAV files are committed to the repository as regression fixtures. If a code change causes the detected pitch to drift outside ±20 cents, CI will flag it.

Repository size note: Keep clips short (≤ 2 s). If the fixture corpus grows large, Git LFS is a future option — configure it with git lfs track "tests/fixtures/audio/real/*.wav".