If all you know is Cream, or even if you think that the Cream stuff is the epitome of his work, you ain't been listening... He's a prolific writer with a very wide tastes and it shows in his solo work so very well. So, if you want to know more about Jack then dig into:
A. "Wheels of Fire" by Cream because it covers both a good representation of their studio work (with a sympathetic producer, Felix Pappilardi) and the spectacle of their live work. And when listening to the live work you HAVE to pay attention to the interplay between them. This is so NOT a turgid R'n'R rhythm section providing steady backing for a guitarist to wank. No, it's three musicians who are actively LISTENING to each other and tossing ideas back and forth. This is, as Jack and Ginger have said many times, a jazz band with a blues guitarist.
B. "Harmony Row" Because it has some of Jack's most beautiful songs, singing, and arrangement. "Hey, Can You Follow", "The Consul At Sunset", "Post War", "Letter Of Thanks"...
C. "Shadows In The Air" for it's Afro-Cuban reinterpretation of older songs (including "Sunshine Of Your Love", "White Room" and "Out Into The Fields") as well as new material.
D. The 50th Birthday concert recordings. There's a double CD set and an smaller single CD issue titled "Sitting On Top Of The World". It gathered people from all eras of Jack's music to that point. Just about everyone EXCEPT Clapton- it's got Ginger Baker, Dick Heckstall-Smith, Bernie Worrell, Simon Phillips, Maggie Reilly, Clem Clempson, Gary Moore, and his sons Malcom and Jonas. They revisit classic Jack material from "Hey, Can You Follow" with just Jack and a piano to the free form jazz of "Over The Cliff", to a heart-breaking version of "Theme For An Imaginary Western", and a killer version of "Politician".
E. The Royal Albert Hall Cream Reunion concerts. This is vital. Why? Because it shows three old friends who respect each others' musicianship playing music with each other because they want to. And it shows who they were forty years later, not a pathetic attempt to pretend to still be 20-something pissed off kids any more.
The key in all of this is to hear how Jack constantly reinvents his lines. He NEVER plays anything the same way twice, but it's always "right" for the song. And also marvel in the way he totally separates his singing from his bass playing. While most singing bassists wind up sounding like either the vocals or (more commonly) the bass part is either simplified or mechanically memorized, Jack doesn't. It's as if he had two brains, one totally focused on the singing, the other totally focused on the bass playing. Wildly improvisational fills and embellishments to both the vocal and bass at the same time.
THAT'S the greatest lesson I learned from listening to Jack. That the music is of the moment and our job is to express the moment.
John