A Scale That Slowly Drifts: Why the Tuning Moves and You Never Notice
Short answer: The whole set of notes moves up and down by a small amount, taking a few minutes for each cycle. Notes that are already sounding stay where they are. Only new notes pick up the new position. So you never hear anything bend, but the music you hear now is pitched a little differently from the music of two minutes ago.
The problem it solves
Each world has a small set of notes. That is deliberate: a small set keeps everything in harmony, whichever shapes happen to meet. The cost is that after an hour you have heard every note many times. Nothing repeats as a tune, but the material is the same.
I wanted the material itself to move, without anyone noticing it move.
How it works
Think of the whole scale as painted on a sheet of glass. The glass slides slowly up, then slowly down, and keeps doing that. The notes keep their distances from each other, so every chord still fits. The whole thing is just a little higher or lower than before.
The important detail is that a note which has already started stays at the pitch it started on. If long sounds followed the glass, you would hear them slide, and a sliding pitch sounds like a tape machine running down. So the drift only touches notes at the moment they begin.
Can you hear it?
Not as movement. I can't, and I know it is there. If you could put a note from now next to the same note from a couple of minutes ago, you would hear that they differ. In normal listening there is nothing to compare against, so it registers only as the sound staying fresh.
I can't prove that last part. It is how it seems to me after a lot of hours with it on.
Why not just add more notes
I tried to keep every choice in this project small. More notes would mean more ways for two sounds to clash. Moving the few notes I have keeps the harmony safe and still changes what you hear.
Try it: leave Ocean on for ten minutes and try to catch the pitch moving. It is free and starts in one click, with no account.
Open Ocean, free