>>9747580Tarkus was pretty much one of my entry-points to prog as a whole, which is probably why I love it so much, even though the B-Side is a lot less "prog" than the phenomenal A-Side. The cacophony of multiple powerful instruments in tarkus (organs, synths, etc) can be kind of overwhelming for some new listeners, but once I got use to it, it just made me appreciate the less chaotic parts of the song (Stones of Year, Mass, Aquatarkus) even more. It took me a couple listens for it to really click, but it helped to focus on specific instruments, rather than trying to take the whole assload at once. The more you understand an instrument, the more you can understand how it fits within a piece, contextually, and the more you can appreciate more complicated pieces of music that use that instrument. Without trying to sound like a pretentious bellend, prog takes a level of knowledge to fully appreciate, like jazz or classical, but it's knowledge that comes from listening to it.
Honestly, their catalog of ACTUALLY DECENT albums isn't huge compared to bands like Yes or KC. My personal favourites are Self-titled, Brain Salad Surgery (the one with Karn Evil 9), Tarkus and Trilogy. It's hard to suggest Works: Volume 1 to anyone, since it varies a lot from track to track (many of the tracks are solo-pieces, pic related)