Just want to note the terrific 1964 D.A. Pennebaker film of the Dave Lambert Singers auditioning for RCA. Lambert was a very early practitioner of vocalese and bop vocals and, of course, a member of Lambert, Hendricks and Ross. The other singers are Mary Vonnie, David Lucas, Sarah Boatner and Leslie Dorsey, none of whom acquired a much larger reputation. Dorsey was killed driving a gypsy cab in 1988.
It's kind of extraordinary to hear 5 singers standing in a circle, all singing into a single mic, wearing no headphones. The singers make constant eye contact with each other, modulating their performances on the basis of a number of audible and physical signals, overt and subtle. The rhythm section plays in another side of the studio, with minimal sound baffling.
In the ongoing discussion about "live" versus "layered" recording (it is ongoing, right?), this film chalks one up for the naturalists.