7 out of 10: As is to be expected from a highly improvisational jazz band, highs, lows and everything in between

Jazz fusion is a dirty word for good reason: the genre abounds in meandering, soulless “songs” that are better off described as excursions into the wilds of boredom. Once upon a time, though, fusion was exciting: Miles Davis’s Bitches Brew is fantastic, Herbie Hancock’s Headhunters a revelation. Happily, Medeski, Martin and Wood (MMW) are steeped in the still-hallowed sounds of fusion’s halcyon days and are fittingly one of the few contemporary jazz trios around who are able to draw a crowd anywhere in the world. Tonight they’re at the HiFi, and tonight they manage to three-quarters fill its sizeable surrounds.

MMW tours as part of the jam-band circuit that The Grateful Dead established and which remains a phenomenon confined to the USA. They have material spread over eight albums to choose from, but live, as all jam bands are wont to do, the songs take on a (long) life of their own.

And live, they push their material into a more avant-garde direction. On Lifeblood, for instance, the first song they play, the delicious groove breaks out into an interlude that sounds like the spinning of an inventive madman’s mind. Billy Martin, MMW’s crack drummer, is particularly creative, even sprinkling a passage reminiscent of gamelan into the section.

The night, though, belongs to John Medeski, the band’s supremely talented pianist. Medeski drives the group, switching effortlessly between organ, keyboard and grand piano while evoking the likes of Gil Evans, Bernie Worrell, Ray Charles and Chucho Valdés. The crescendos the band manages to build on the back of the inspired keys are a delight, especially when they lock into the hardest of grooves. Not only does he have the necessary touch of a jazzman, he also manages to turn his keys into an aggressive, howling beast that would not be misplaced on stage with Rage Against The Machine.

If there is criticism to be made, though, it’s the standard one made of improvisational bands: a lack of cohesion. The abrupt jumps from one style to another often sounds as unnatural as switching between radio stations, not to mention the free jazz sections that are at times as difficult to penetrate as they are inventive.

Nonetheless, MMW are a honed live band. Their many years playing together means musical ideas are constantly bounced between each band member with ease. While this improvisatory skill can sometimes be overplayed, the band is always interesting, daring and a welcome deviation from the norm.