The Austin-based Hot Club of Cowtown explores the space where early jazz met Texas swing, where Joe Venuti and Eddie Lang met Bob Wills and His Texas Playboys. Guitarist Whit Smith and fiddler Elana James have become a world-class country-jazz duo, challenging each other and reading each other's minds at every turn. Add in the insouciant lyrics of the era and the vigorous slap-bass rhythms of Jake Erwin, and you've got virtuoso small-group western swing that's beyond infectious. If you've seen the Hot Club before, be advised that they're only getting better—they went on hiatus, got back together, and came out of it stronger. By now they're one of the great improvising bands in any genre. Their latest album, "What Makes Bob Holler," is a tribute to Bob Wills and delves into some of the Texas Playboys' more unusual material.