Something you might not have known about the C64's sound chip (SID) Show more
Nowadays, computer sound is produced digitally and fed through a digital to analog converter (DAC) to drive speakers, headphones, etc. That's been true since at least the Soundblaster came out. Even when the sound card had an on-board synthesizer like the Yamaha OPL3, that put out digital which was then fed to the DAC.
Before that, though, sound chips in computers, including SID, were digitally controlled *analog* synthesizers.