Back Door Slam lays it down without turning it up

If you’d been looking for a technically impressive display of blues-rock chops Tuesday night, it’s unlikely you’d have had more luck than if you’d dropped in at the Viper Room. That’s where Back Door Slam, a young trio from the Isle of Man, played the first of two shows in support of a debut album that’s earning a bit of buzz among folks who view the history of pop music since 1967 as an unbroken downward slide.

As they proved in their hour-long set, these boys can lay it down: Like Jonny Lang and Kenny Wayne Shepherd before him, 20-year-old frontman Davy Knowles possesses the voice of a man three times his age, and he plays guitar with the assured dexterity of a lifelong pro. There’s no question that Knowles is Back Door Slam’s focal point; bassist Adam Jones and drummer Ross Doyle drove the music with a heavy groove, but they seemed content to do it from outside the spotlight’s glare.

Unfortunately, though his abilities might warrant the attention, Knowles didn’t appear to be sure of what to do with the spotlight, either. For all its rootsy integrity, Back Door Slam’s performance Tuesday exuded about as much personality as a library card.

Between songs, Knowles came on like quite a chipper bloke, thanking the crowd for coming and flashing a goofy grin that reminded you that the kid’s not old enough to order a beer. But the music itself felt studied and joyless; it said nothing about “youth and young manhood,” as a much more distinctive blues-rock outfit -- Nashville’s Kings of Leon -- once called it.

The band closed with what Knowles dubbed “an attempt” at Jimi Hendrix’s “Red House.” For the first several minutes, it was business as usual. But near the end of Back Door Slam’s version, Knowles bent over his guitar and peeled off a noisy one-note solo that lasted for nearly 30 seconds.

The appealing petulance of the move did right by the memory of Hendrix. More important, though, it sounded like something a 20-year-old would do.