Pat Metheny Unity Group: Kin Nonesuch/Warners

Guitarist Pat Metheny can be hard to pin down. To hardcore fans he is the musical deity who leads the Pat Metheny Group, a crafter of blissed-out grooves and soaring melodies. To others, he is a vaguely suspect purveyor of smooth jazz, casting his undoubted virtuosity on the desert air.

Among musicians, the 59-year- old is generally acknowledged as one of the guitar's finest exponents, an effortlessly fluent improviser whose influence on his instrument is comparable to John Coltrane on the tenor saxophone. Some may grumble at the lack of roughage in the Missouri man's regular diet, but when he puts his electric band aside and makes a pure jazz record, as he regularly does, most of the grumbling is silenced.

Metheny, for his part, seems entirely unconcerned with what other people think. He sells records in quantities that would give most jazz musicians palpitations, and he clearly feels free to wander wherever his muse leads him. And yet recently it has looked as if he was trying to unite the two sides of his music – to take the rough with the smooth.

Enter the Unity band, formed in 2012 and apparently designed to combine all musical virtues. In saxophonist Chris Potter Methany had an improviser with powers equal to his own; in drummer Antonio Sanchez a percussionist with superhuman levels of rhythmic independence; and in bassist Ben Williams, a safe pair of hands to hold it all together. The repertoire was polished, but there were patches of definite rough, and if extremists at either end of the spectrum were disgruntled, well, Methany didn't really care. Neither did most of his listeners.

Now he has taken the Unity concept a stage further by adding Italian multi-instrumentalist Giulio Carmassi, whose lush keyboards, wordless vocals and sundry horns make this new group even more reminiscent of the polished PMG sound. That will be encouraging to some and worrying to others.

To these ears, the important thing is that when the guitar solos start, it’s Pat Metheny. Rough or smooth, they don’t come much better. patmetheny.com CORMAC LARKIN