I am closest to fellow WikiTreer, Pip Sheppard. We are 14 degrees apart, and his 4th great-grandfather and my 5th great-grandfather were brothers! Pip was my greeter when I joined WikiTree, so this was fun to learn!
As for the jazz musicians, my closest connection is Jack Purvis, at 16 degrees. He is also a cousin, the only one for me in this group (unusual, I usually have at least a couple!)--13th cousin, 3 times removed.