Throughout his four-decade career, John Hammond, Wednesday, March 28, at the Gothic Theatre,has been known as a gifted interpreter of the blues: In the early days, young Hammond channeled the raw power of artists like Robert Johnson and Mississippi John Hurt for a new audience, at once helping to preserve the tradition and casting it in a new light. It seems fitting, then, that Hammond has most recently paired with Tom Waits, who's made an art form of brilliantly morphing the blues (and almost every other) genre. On Hammond's latest recording, Wicked Grin, the vocalist/guitarist/harmonica player repackages some of Waits's most acclaimed work -- from the Heartattack and Vine era through the most recent Mule Variations -- with Waits at the production helm. Hammond knew it would be difficult, if not impossible, to improve on Waits's bedraggled presentation, so he didn't try: Instead, Hammond let his own considerable talents shine through in a fairly straightforward, but no less gritty or appealing, album. Hammond, who will perform material from Wicked Grin as well as his notoriously large repertoire during Wednesday's performance, seems to have plenty to smile about.