Once upon a time, he was the manic grasshopper frontman for the J. Geils Band. Now, with Sleepless, his sixth solo outing, Peter Wolf’s ’70s whiskey has completed its transmogrification into fine wine. With a batch of heartfelt originals and hand-picked covers that haven’t been bludgeoned to death with over-production, Wolf has delivered a set of blues-, soul-, and country-oriented rock that is a study in unforced finesse. Dig the duet Wolf performs with good buddy Mick Jagger on the Stonesy country-rock single “Nothing but the Wheel.” Meanwhile, Keith Richards pops in to grind his axe on the Sonny Boy Williamson blues churner “Too Close Together.” Then there’s the gossamer ballad “Five O’Clock Angel” (an ode to Wolf’s friend, playwright Tennessee Williams), the acoustic shuffle “Hey Jordan,” and the Otis Rush gem “Homework.” Wolf hasn’t whacked a home run with Sleepless, but it’s one helluva pretty triple.—AZ