Practising with something to aim at

Notes, not a score

karanow draws a runway of notes moving right to left, and your own pitch is drawn on top of them as you sing. Hitting a note makes it grow and glow; being under it looks like a thin line sitting under the note. There is no number at the end, because a number is a verdict and this is a mirror.

The notes are read from the original singing on the very recording you put on — not from sheet music, not from a generic melody for that song. If you are singing along to a live version, you get that version’s phrasing.

Why it draws notes and not a curve

A curve is what the pitch tracker actually produces, and it is unusable. People sing with vibrato and slide into notes; the instantaneous pitch wanders above and below the semitone constantly. Measured on real recordings, a quantised frame holds still for one or two frames — 80 to 160 ms — which draws a wriggling worm rather than something you can aim at.

So the line is cut into notes the way music transcription does it: split on pauses over 0.2 s and jumps of a semitone and a half, take the median within each segment rather than the mean — the median is a pitch that was actually sung, while the mean of a slide between two notes is a pitch nobody sang — and drop segments whose ends differ by a semitone, because those are slides rather than notes.

It learns the song once

The first time you play a song, the pitch line is built as the separated vocal goes past. From the next play onwards it is already there, about seven and a half seconds ahead of you, so you can see what is coming rather than react to it.

Once written, a note never changes. A reference line that moves is worse than one that is slightly off — nobody can sing to a target that keeps adjusting itself.

Recording a take that lines up

Recordings map file time to song time, so a take you start halfway through a chorus still lines up with the song when you listen back. The file holds your voice; it is on your Mac, and you can delete it whenever you like.

It is still in beta

The pitch runway carries a beta label in the app, and it carries one here for the same reason: it works, and it is not finished. Saying so is the reason to believe the rest of this page.