What one track means here
A MIDI track can contain several notes at the same time. That makes chords possible, but it does not identify which source instrument played each note. In the current converter, the browser model returns a shared list of pitches, start times, durations, and amplitudes. The export step sends that list to one MIDI-file generator without assigning instrument names, stems, or separate channels.
The file header may report two raw tracks. One is structural metadata and the other is the single musical note track. Importing the file into a DAW therefore gives you one editable part, not a session with automatically separated instruments.
What we measured in a local browser run
We created a four-second WAV with no copyrighted recording: isolated C4, isolated G4, a simultaneous C4-E4-G4 chord, then C3 and C5 together. We ran that file through the live converter code at its default sensitivity and minimum-note-length controls.
| Checked item | Local result | Meaning |
|---|---|---|
| Detected note events | 9 | The model returned a combined note list, including repeated edge detections. |
| Raw MIDI tracks | 2 | One metadata track plus one musical track. |
| Musical tracks | 1 | All detected notes were placed together. |
| MIDI channels used | 1 | No per-instrument channel split was created. |
The nine detected notes were C4, G4, C4, G4, E4, C3, C3, C5, and C3. The repeated C3 shows why a synthetic test can document file structure without proving transcription accuracy. The result applies to this controlled file and the current site code.
How to get separate MIDI parts
- Start with audio you are allowed to use. Keep the source rights and platform terms in mind before saving or processing media.
- Separate or obtain the audio parts. Create individual vocal, bass, piano, guitar, or other stems outside this converter.
- Listen for bleed. If another instrument remains audible in a stem, its notes may also appear in the MIDI draft.
- Convert one stem at a time. Use a clear filename so each downloaded MIDI part can be identified later.
- Import each file onto its own DAW track. Assign the intended software instrument, align the starts, and edit wrong or duplicate notes.
Can it still detect chords?
The underlying browser workflow is polyphonic: it can return overlapping pitches, and the controlled test placed multiple simultaneous notes in the output. That is different from instrument separation. A chord from one piano and notes from several instruments can both become overlapping events in the same MIDI track; the file does not tell you which source made each pitch.
When a combined draft is useful
A single combined part can still help when you want a rough harmonic sketch, a starting point for manual editing, or a quick view of prominent pitches. For a clean arrangement, prefer an isolated source and verify every part by ear. If playback uses an unexpected piano sound, see the instrument guide. For short duplicate detections, use the extra-note cleanup guide.