Here's a new capx, but I guess it's not really simple.
It takes a file and loads it into a text variable with ajax.
The format of the file is just comma seperated:
Notes are defined by the note and octave: ex: a4, a4#, etc...
Rests are defined by "r"
The meat of it is it uses a number i to define where we at.
It get's the note from the music with tokenat(music, i, ",")
It takes that and converts it to a frequency. Here I used an equation and a lookup, but it can all just be a lookup.
Next it get's the duration with tokenat(music, i+1, ",") and sets a timer and adds 2 to i.
When the timer finishes it goes again.
I added little stuff here and there like fading the volume, and stopping if something invalid is in the file.