Why those twelve notes at the piano, and not other notes? What other notes are there, and what musical pathways do they open? What does "in tune" mean, anyway?

Spend the week delving into these and other xenharmonic questions via:

 -  choral singing

 -  a retuned piano, harpsichord, and more!

 -  your own acoustic instrument

 -  Sagittal notation, an elegant new notational system

 -  the Sagittal Songbook: a collection of thoughtfully and adventurously-tuned music