Half of it is classic Baby Boomer stuff: Stones, Beatles, Dylan, Who, Joplin, Ronstadt, netc. Lots of people have these, but where I truly built their catalogs is through bootlegs. I have a complete Beatles catalog (well, minus the newest song Now & Then), but twice as many bootlegs. The same is true for Dylan, with only the lp Self-Portrait absence. Dylan may be the most bootlegged musician on the planet.Well dang…Bruce could just about run his own radio station!
I have additional singer/songwriters I favor: Browne, Cohen, Prine, Hiatt, Baez, Cash, and others less known. For a couple of years I went on a folk kick, and I explored jazz, particularly the period after Big Band and before 1970. I settled on Hard Bop, which was jazz mid-/late1950s > mid-1960s. I love Hard Bop; great music, well represented on Blue Note.
There are other genres represented. Basically, if I liked a song, I got the album (I quit singles long before CDs showed up).