This is it! The original Les Swingle Singers, arranged and conducted by Ward Swingle. Half of this rerelease was from the l963 recording which won a Grammy for "Best Performance by a Chorus." The first Jazz Sebastian Bach was a 1968 album called Bach's Greatest Hits here in the US where Les Swingles won a Grammy in the category "Best New Artist." You'll find over sixty-five minutes of jazz/Bach sung with only the bass and drum (mostly snare) to accentuate rhythm. They became world renown because scat is an understandable language everywhere in it. None of Bach's work has been changed, not a note added or taken away! This is not improvisation (though two pieces were transposed to accommodate vocal range).