It's just the vocalists and drums. It is so cosmic, so warmly human, the song so unforgettable (it's not the standard by the same name), the arrangement so beautiful, it moves me very much. Doowop from outer space? Yes and more. It's extraordinary. Get your ears ready, and listen!
Go to http://bairdhersey.com/media/recordings/ to hear it. Then go to itunes https://itunes.apple.com/us/album/my-foolish-heart-enhanced/id597676928?ls=1 and plunk down your 99 cents and get it.