[vardump]

Arpeggio was everywhere, doable on pretty much any sound chip.

I think what sets SID apart are things like high/low pass filters, finely adjustable PWM width and maybe even finely tunable pitch.

[_spduchamp]

The SID chip is an analog semi-modular synth with digital control. The arpeggios unfortunately seem to be so heavily leaned on that it pretty much defines the chiptune sound, and those arpeggios could be played on lots of other systems, but the SID, when you dig into the beat frequencies and filters is a rich sonic world like no other.

Here is that BASIC beat frequency drone (no filter stuff) https://youtu.be/k2YZkSq2gcY