There are exceptions to the rule, of course. The entire outputs of Can and Earth, for example, are based on collective jams that are gradually sculpted into song forms. Neil Young & Crazy Horse and - at their sharpest - The Grateful Dead have habitually stretched tunes to epic proportions; although both feature prominent soloists, it's really about the collective, combined totality of sound rather than a showcase of individual expertise.

Brooklyn-based guitar ace and, latterly, singer Steve Gunn can now be added to this choice group of genuinely compelling devotees of jamming. The follow-up to last year's justifiably praised Time Off (Gunn's first record to feature prominent vocals and relatively conventional song forms after several years at the forefront of US guitar avant-garde and numerous collaborations, such as the great Golden Gunn LP with Hiss Golden Messenger's MC Taylor and recently released, excellent duo album Cantos de Lisboa with cult free-folk-rock master Mike Cooper) started as a set of stark solo demos that were gradually expanded into these warm widescreen workouts at New York's seminal Black Dirt Studio in the company of Gunn's regular trio and selected guests.

Never less than thoroughly involving, the outcomes are frequently sensational. Great as Time Off was and is, it sounds little more than a rough sketch next to these eight unhurriedly evolving, luxuriously layered cuts. Fuelled by several guitar licks waltzing harmoniously around the mix, as opposed to stepping on each other's toes in a battle for prominence (check out the lap steel weeping drowsily through the earthy slow-motion stomp of the title track), Way Out Weather mixes various musical styles - folk, classic rock, psychedelia, space rock, dub hues, West African grooves, open-tuned raga drones - to arrive at a genre-defying, expansive sound that's simultaneously tight and totally, winningly loose, sparsely uncluttered yet richly textured in a way that rewards repeated spins.

That Gunn and co. play with genre convention-dodging versatility throughout isn't much of a surprise by this point; after all, Gunn's roots in the 'American primitive' solo guitar tradition of John Fahey et al dictates a certain level of open-eared dexterity in fretboard acrobatics. The giant leap forward that Gunn's songwriting has taken since Time Off is a bit unexpected, however. By the time the horns punch in towards the end, 'Milly's Garden' has built up more than just a subtle whiff of the Stones at their Muscle Shoals-visiting, Sticky Fingers pomp, with faint echoes of the Grateful Dead and - in the earthy funkiness - Little Feat chucked in too. At the opposite end of the swagger scale, the intricate odd-folk rhythms of "Wildwood" - with the plucking of banjo to add drops of swamp water - and the harp-enriched "Shadow Bros" excel as thoroughly modern takes on the American folk song forms, whilst the spectral "Atmosphere" carries a hint of Black Sabbath's "Planet Caravan".

The ensemble playing lifts the already strong material to truly compelling heights. Good as the tune is, the gentle country-rock of "Fiction" doesn't really lift off until the band shift gears some four minutes in to unleash a jaw-droppingly beautiful circular guitar movement, the sweet, soothing main melody deliciously counterpointed by stinging avant-rock abstractions hammering away just beneath the surface; it's doubtful a more satisfying sixty second salutation to the undimmed expressive power of the guitar will emerge anytime soon. Likewise, the already mighty "Milly's Garden" is catapulted upwards by a magnificent middle part composed of, well, noodling. In a way that summarises a lot that's so refreshingly great about the playing on Way Out Weather, nothing all that extraordinary happens and there are few fireworks to gawp at. However, the low-key dynamics and gradual build-up of momentum reaps much richer rewards than any bout of frantic soloing ever could.

All that and we've not even discussed the album's highpoint yet. That accolade goes to the closing "Tommy's Congo", a hypnotic, propulsive slice of forbidding pure musical voodoo reminiscent of the desert-blues hues of criminally obscure Finnish band Plain Ride's latest album Skeleton Kites, a moment of overdrive and groove-fuelled oomph on an otherwise languid album, which suggests that, having hit the jackpot on Way Out Weather, Gunn might achieve something even more remarkable next time around.