It's fun to change time signature mid-song

[Kim Lajoie]

Something for the music theory forum this time.

The objective was to change time signatures multiple times as seamlessly as possible.

Starts out at 100bpm, 4/4.
At 2:00 shifts to 15/16, configured as 5/4 in triplets. Tempo slows down slightly so bar length stays the same.
At 2:53 shifts over 4 bars to straight 5/4 (20/16) by gradually straightening the swing from the triplets.
At 3:26 changes to 4/4, but quaver length remains the same. Result: bar length contracts by 4/5 and tempo speeds up 25% to 125bpm.

Just for fun, I sneaked in a short section with multiple key signatures playing simultaneously. Starting 3:42, the rhythm section (piano and electric bass) play a Abm, E, Gb, Db cycle. Tron flute plays a melody in C Major, and trumpets do a quick fanfare in F# Major.

Download the song. Talk about it.

-Kim.