Onstage with the folk Warner Williams and Jay Summerour

It looked as though a few hundred people had stumbled onto a back-porch blues jam and, liking what they heard, decided to stay as Warner Williams and Jay Summerour played Saturday at the Two River Stage.

The Piedmont-blues duo kept things simple with nothing more than a guitar, harmonica, the occasional tambourine shake and friendly dynamics. The 45-minute set was refreshingly stripped-down yet it still managed to deliver a bounty of eclectic sounds.

Williams and Summerour delivered much more than blues. With Williams plucking his 12-string guitar and Summerour adding harmonica, whistles, claps and tambourine, their set shifted from straightforward blues to country favorites to ragtime music and back again. They even played a few popular favorites such as “Blueberry Hill” and “Your Cheatin’ Heart.”

And despite a wicked, blustery wind and background noise from the Heritage Stage, the duo’s performance never lost its musical potency, or that fun, casual feeling of being at one heck of a backyard party.

– George Bragdon