Found a favorite band through a similar technique: pile of CDs given from a friend who worked at a music store and no one wanted them.

You have to be willing to sift through junk. Which I think is hard for many to accept. However, the algorithms are often giving you junk anyway. Kind of no way around it.

Yeah, most of the CDs there were pretty unremarkable; a lot of them were unsurprisingly stuff that was extremely popular (since those have the most CDs available). A lot of the stuff that wasn't extremely popular was pretty bad.

Still, in that 300, there was about ~30 albums that I hadn't hear of that I ended up really liking.

Took awhile to sift through them all, which is why I haven't done it again, but it was a fun experiment all the same.