Stromian Tuplet Notation

Nested tuplet from polyriddim by phonon

Nested tuplet used frequently in The Black Page by Frank Zappa

8[4:3+7:5][2+7:6+3]/7

Stromian tuplet notation is a system for expressing tuplets. The main purpose of STN is to convey complicated tuplet ideas over text. The system strikes a balance between legibility and efficiency.

It can get frustrating when you send your homie a Fizz WIP and they ask “what’s that rhythm 8 seconds in?” To which you reply “It’s a bar long triplet but the first and last of those 3 beats are both nonuplets, and the beat in the middle is just filled with 8th notes. Or 8th note triplets rather... Never mind, you get what I mean. Actually I'll draw a picture and send it...". STN allows you to reply with "it's 3[9:1+4:1+9:1]:2/2" like an absolute chad.

Nested Tuplets

The notation system used on the Metr tool on chambercode.com is very similar to STN for nested tuplets, the main difference being that it doesn’t have STN’s redundant numerator.

Stromian vs. Metr notation

	Tuplet	Notation
Stromian	11:8 with a nested 8:6 at the beginning	11[8:6+5]:8
Metr	11:8 with a nested 8:6 at the beginning	[8:6+5]:8

Limitations

Ambiguity

When written with STN, the exact length of the tuplet can be ambiguous. If there’s a 4 in the denominator, that could mean that the tuplet is 4 quarter notes long, but it could also be 4 eighth notes, 4 sixteenth notes, etc. This ambiguity can be solved by writing the denominator as a time signature instead of a plain number.

11[8:6+5]:8 —> 11[8:6+5]:8/8

Legibility

Nested nested triplet

A triplet inside of a nested triplet is pretty easy to conceptualize when reading it on sheet music, as opposed to STN, where it would be written like “3[3[3:2+1]:2+1]:2”. STN has its limitations, but it allows those familiar with it to glance at “11[6+9:5]:8” and think “ah yes, a 11:8 tuplet with a nested 9:5 at the end”.