aria-tree-walker and musical score notation

The example of the C major scale below was built using various tools and sources. A music XML sample from the MNX specification was converted to SVG using the Open Sheet Music Display Demo (which leverages vexflow). Music Braille was created using freedots (with some mild interpretation for transitioning from an print/embossing format to the context of web-based interaction and exploration). Finally. speech text was created by hand following Roma Dix, Dictating Music (from ICEB)