The sound of the high speed tape drive when booting up (or playing Buck Rogers) still remains fresh in my mind. That, and the daisy wheel printer's rhythmic whir-rat-tat-tat-chunk-whine whenever I printed out a letter asking for another tape drive.

I also had my first generative music experience with the Adam - POKEing numbers into various registers would trigger the waveform generators and if combined with various patterns/functions (sin, cos, and the like) would make some cool sequences.