A lot of good titles mentioned, though I beg to differ that some of those mentioned are certainly very popular and sold a A LOT. Not the below.
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Second for Booker Little "Out Front" on Candid - masterpiece and should be heard by anyone interested in who Miles referred to as if Booker had lived longer, would have eclipsed nearly every trumpet player out there - they went to the same music school in MD at different times. He and Dolphy were soulmates as well, and cut more well known albums live together that need no explanation. He also was part of Max Roach's band before going solo. Little tragically died at 23 of complications with uremia, not anything but that. Nat Hentoff was devastated - they were very close, and of course the two dirges on here will make you stop.
Mingus - "East Coasting" on Bethlehem - under-appreciated is an understatement. As a Mingus freak, this is in my top 3. Like a foggy day with beautiful flowing charts and Dolphy's bittersweet wail once in a while. It is a tone poem, and should he heard in full, Accessible in a mysterious way. There is a reason Mingus, if ever, did not put other musicians names on his albums. That was not the point like other labels using it as a marketing gimmick.
Second nearly all the later Chet Baker LP's while rebuilding his embouchure in Europe.
Coltrane - "Ole" - I actually am not sure if this one is/was popular. However, the track "Ole" across all of side one is IMHO, and virtuoso performance of every musician - two bassists included bowing back and forth between each other at the height of the chart. Side 2 of course needs no explanation.
Music, Inc. - "Live at Slugs" - whatever versions you can find. Charles Tolliver, Stanely Cowell, Cecil McBee, and Jimmy Hopps. Something happened during those shows, that, for me, is magical and transcends most jazz of that time and now.
