[racket] music mini-language

Anyone currently working with music mini-languages in Racket?

Reason I ask... In my iRobot Roomba Racket interface, I currently have a 
simple music mini-language that lets you specify a sequence of pairs of 
note/frequency and duration.  (Roombas have a simple single-voice 
note-playing capability.)  To make encoding of, say, piano sheet music 
easier in the mini-language, I'd like to adopt more of the conventional 
music notation conveniences, such as time signatures.  I've found 
"https://ccrma.stanford.edu/software/cmn/' for Common Lisp, so I'm 
wondering whether I should implement a subset of that, or something else 
that Racket people are already using.

Neil V.