Don’t know how I came across this one, but this is a truly awesome (in the original sense of the word) performance of "Summertime". That base player must have finger joints made out of pure titanium…..
After that, why not listen to their rendition of Air as well…
Applied Abstractions 
As one who fiddles with a bass now and again (pardon the mixed terms!) this is indeed quite an amazing piece of musicianship. Early on in this recording, I found myself thinking, “It’s amazing that he can play this, but why bother? A bass (especially an acoustic double bass) rarely makes a great solo instrument. But as the piece built, it really worked – a fine bass solo and a superb example of a jazz riff on an old classic!