What we tested
We generated three mono 16-bit PCM WAV files at 22,050 Hz. Each file contained the same 440 Hz A4 tone beginning at 0.250 seconds, lasting 2.000 seconds, and reaching the same 0.72 peak amplitude. Only the linear fade-out changed: 0.02, 0.40, or 1.20 seconds.
Every file used the same 0.02-second attack and 0.25 seconds of true silence after the tone. We ran all three through the current local converter at its default note-sensitivity and minimum-length settings, then inspected the exported MIDI files.
| Fade-out | MIDI events | Final MIDI end | Main velocity | File size |
|---|---|---|---|---|
| 0.02 s | 1 × A4 | 2.254 s | 78 | 59 bytes |
| 0.40 s | 1 × A4 | 2.196 s | 77 | 59 bytes |
| 1.20 s | 2 × A4 | 2.173 s | 78 | 68 bytes |
What changed in the MIDI
All three detections began at 0.221 seconds. The 0.40-second release ended 0.058 seconds earlier than the 0.02-second release. Extending the fade-out to 1.20 seconds moved the final end another 0.023 seconds earlier.
The longest release also split the sustained pitch: one A4 ran from 0.221 to 1.637 seconds, followed after a 0.012-second gap by another A4 from 1.649 to 2.173 seconds. The second event had velocity 64, compared with 78 for the first. Every run returned HTTP 200, used one musical track, and produced no console errors.
How to handle a fading note
- Compare the MIDI end with the waveform. A quiet release can cross the detector's boundary before the source file reaches silence.
- Check for a split near the tail. Merge adjacent same-pitch events when they represent one held note.
- Adjust the note-off by ear. Extend or shorten the MIDI note in your DAW when the musical release matters.
- Test your own source. Pitch, timbre, noise, reverb, and converter controls can change the result.
What this test does not prove
It tests one synthetic A4 at one peak level with three linear releases. It does not cover acoustic decay, compression, reverb, mixed recordings, direct YouTube-link input, other pitches, or other converters. It does not establish a universal fade-out threshold.
For true silence after a note, see the trailing-silence test. For repeating decay, use the echo test. For the opposite envelope edge, see the fade-in test.