[vidarh]

You could play music on the C64 by sampling the tape ports 1bit input and twiddling the sound chips volume accordingly.

You could of course store the samples too, to play back later, but doing realtime sampling into 64KB of RAM didn't exactly let you store much... And a 1MHz CPU didn't let you do much compression if you wanted to keep up..

[cluckindan]

You could in fact play four sample channels (with filters) plus two SID channels. However, the tech to do that was only discovered around 2008.

https://youtube.com/watch?v=ZMioAPZcays

https://youtube.com/watch?v=D2lEVw7fsMY