The ST's floppy controller is the COTS WD-1772, and that series of controllers was extremely popular in a lot of 8 bit machines. The 1770 is a familiar number to me as being the one they had to bodge into the BBC Micro because supplies of the controller it was designed to use had dried up.

Its sound was basically the Yamaha AY-3, a chip that as pretty impressive for its time and again appeard on many eight bit machines such as the BBC Micro (again) and newer ZX Spectrums.