Al Jarreau was in grad school at the University of Iowa. He performed about one Sat. night a month at the Trap, which was in Cedar Rapids. I rode to the gig with him a few times. He was then a Mathis/Hendricks inspired jazz singer. Everything in his later "popish" style was in place at the time. He made a record for Studio 4 in 1965 with a Tender Trap rhythm section. It was not issued at the time but was issued on vinyl by Bainbridge around 1980.
The Iowa City jazz scene was interesting at the time. Dale Oehler, the pianist on the JR record has/had a career as arranger/producer in LA (run an AMG search to see all the credits). John Wilmeth, JR's IC bassist also played trumpet and you can do an AMG search on him too. The regular drummer was Rusty Jones (nephew of Isham) who later toured with George Shearing for a few years. He later became a staple in the Chicago club scene.
Paul Smoker had his own scene going on at the time, as did a dandy tenor player named Kent Kohea.
As I was about to leave the university scene, JR was talking of moving to LA and the rest of the guys enticed their friends Dave Sanborn and a fine drummer named Tom Radtke to transfer from Northwestern to Iowa. You all know what happened to Davie, but Tom became one of the two "on call" studio drummers in Chicago.
All of these people made it into AMG, I see.