There's no credit given so it's hard to be absolutely sure, but I'm pretty confident that that HTML5 music engraver is using symbols from a music font I recognise. Ooh!
("If there's one thing I know better than anyone, it's my own work." – Col. William Stryker)
no subject
("If there's one thing I know better than anyone, it's my own work." – Col. William Stryker)