Composer Karim Haddad’s Motets present a complex rhythmic language based on the medieval concept of prolation taken to a modern extreme. The notation is beautiful and evocative, but tremendously difficult to realize as a performer.

Conceptually lucid, impossible to perform (currently)
Realizing this (thanks Karim!), the composer has also presented a ‘quantized’ version of the score, translating the many layers of tuplets into their duration in milliseconds, then mapping this information onto the closest approximation afforded by 2-8 subdivisions per quarter note. The result can be extremely variegated series of tuplet subdivisions of a regular beat, requiring accurate placement of say, the final septuplet of one beat, and the final triplet of the following beat, as in the below example.

Eminently readable and aurally identical
This notation, while immensely more familiar and readable, poses a unique challenge. It requires of the musicians the ability to switch subdivisions in some cases, every beat. This is not something that musicians are normally trained for; we are usually very good with duple and triple subdivisions of the beat and can fake our way through fives, and switching between them involves some grinding of gears. I wanted to train myself to instantly hear these higher-prime subdivisions in the same immediate way we hear duple and triple divisions.
I began by practicing each division on its own, putting on the metronome and simply subdividing, for example, an even five, ensuring that each attack was of equal length and unaccented. Of course 5s and 7s end up in groupings of 2 and 3, but I found it most useful to keep the subdivisions flexible, later improvising groupings with the metronome, exploring aspects of the subdivision. Then I would move between several subdivisions, alternating fives and fours, feeling the even pulse of each, and how they relate. After I felt more comfortable in each subdivision, I wanted a way to practice long strands of changing subdivisions like I knew I would find in the Motets. Using a favorite tool of practice and composition, random.org, I created a string of hundreds of random numbers between 2 and 8, presented in 4 columns. I put my trusty Dr. Beat on 4/4 and dove in, reading each number as a subdivision. It’s tedious work, but even a few sessions found me more confident in dealing with simple subdivisions of the beat. In a way, there’s no difference between triplets, sixteenth notes, and septuplets; they’re all periodic subdivisions, evenly filling the space between two pulses. There’s no special secret to learning them, only the familiarity that we have from years of duple/triple based music that has led us into rhythmic complacency and fear of the higher primes!