A regular VIC-20 sound chip sound is heard in some demoscene productions. The chip is actually interesting to explore, as it is capable to produce not just square wave, but bit patterns. I've tried to exploit this trick in the PETSCII Robots driver, but it didn't turn good enough. There is a lot to be explored. A glimpse of this is heard in the video linked by utz.
As for 1-bit stuff on VIC-20. Well, it is 6522 then, so exactly the same thing as the stuff that I did for the PET.
A spoiler: a native PET PeskySound-driven editor has been put into the queue of projects some time back. Should be portable to the whole 6522-equipped Commodore range easily enough.