A multi-instrumental complex rhythm

The figure below is the sound waveform for a passage from the jazz piece, Unsquare Dance.   

Unsquare Dance Sound Waveform
Play audio

The image below is of three percussion scalograms for this sound waveform.  The top percussion scalogram corresponds to the highest frequencies of the sound (above 3000 Hz)---it marks off the hierarchy of percussive strikes of the drummer (initially rapid strikes of drumsticks, followed by slower tempo hand clappings).  The middle percussion scalogram corresponds to mid-range frequencies (between 400 and 3000 Hz)---it marks off the hierarchy of piano notes.  The bottom percussion scalogram corresponds to lowest frequencies (below 400 Hz)---it marks off the hierarchy of bass notes.  Notice the timing of the beats---indicated by the scales in the figure---the time-signature of 7/4 for the piece is captured by this percussion scalogram analysis.  Notice also that
the drummer and piano player are playing 7 beats to a measure of 4, and the bass player helps them keep to this difficult rhythm by playing a steady 4 beats to a measure.  To play videos of each percussion scalogram, click on one of the links below.

 

                                                                          Multi-instrumental Percussion scalogram


Play video for drum strikes and hand claps:  AVI format (best)   RAR (compressed AVI)    MPEG format (most compatible)

 Play video for piano notes: AVI format (best)   RAR (compressed AVI)   MPEG format (most compatible)

 Play video for bass notes (bass notes amplified): AVI format (best)   RAR (compressed AVI)   MPEG format (most compatible)