Congrats! I think he goes to the same general program BCSA, but with the option designated as Music Technology, which in turn consisting of Audio Recording & Production and Sound Theory & Practice sub fields. Take a look at this music concentration sheet: https://www.cmu.edu/interdisciplinary/assets/bxa-music.pdf.
Separately, I’ve read that BCSA kids spend about 75% time on CS, and 25% on art questions about the BXA program at CMU - #5 by parkinglots