A look at what is happening in the world of the arts.

Carlsberg Rhythm and Roots Festival.Various venues, Kilkenny

We are all inmates of the Americana correctional facility, a travelling unit based in Kilkenny every May bank holiday weekend . Among its residents this year were Colonel JD Wilkes, a frontman that makes Iggy Pop look like Dickie Rock; Spo-Dee-O-Dee, from the deep south of . . . well, Germany; Holly Williams, granddaughter of former correctional facility head boy Hank; and so on. In other words, it's the Carlsberg Rhythm and Roots Festival - cowboy boots and rockabilly threads are optional, but an open mind is a must.

You'd certainly have to be open minded about Entrance, aka Guy Blakeslee. Think a car-crash mixture of John Fahy, Marc Bolan, Skip James and Tiny Tim, and you'd have only half an idea of what this dishevelled, open-tuned blues guitarist was like when he played to a gobsmacked/bemused crowd in a back room at Ryan's pub on Friday night. Art Brut or brutal skeletal blues played by someone who looked like a refugee from functional life? The jury has yet to make a decision.

Over at the River Court Hotel, there was no doubt about the quality of Son Volt. Here was a band, fronted by Jay Farrar and guided to heavenly bliss by the virtually indecent knee-trembling guitar work of James Walbourne, that integrated astute, propulsive rock with intuitive, rough-hewn Americana. Gig of the weekend, perhaps?

Saturday started quietly at noon in The Widows pub with Jesse DeNatale, a US singer-songwriter good enough to still the lunchtime mutterings of a bleary-eyed crowd. The only sounds to be heard apart from DeNatale's elegant, occasionally too lengthy folk/Americana were ice cubes clinking against each other.

Over at Ryan's, Ben Weaver was nowhere near as cool or connective. Perhaps it was too early in the day, but his take on Americana noir bordered on the pedestrian. Joe Whyte (at Dempseys) suffered from a similar fate - his overly gratuitous product plugs aside, here was one guy whose roots/rock hybrid was one roots/rock hybrid too many.

Carolyn Mark (at The Widows) was the joker in the Kilkenny pack: funny, engaging and completely lacking a personality crisis, she ripped through her hour-long set with little subtlety and loads of nerve. Co-headliner John Eddie, meanwhile, postponed any notions of slumber with his rowdy Southern roots/rock.

After that, it was time for another burst of Son Volt (at the River Court) if only to confirm that the previous night's gig was not a figment of a fevered imagination; yep, still terrific.

And so is this festival - after eight years it's still full of surprises, more often than not very good music and the kind of instinctive programming that continues to bring to the wider public genre-defining, genre-twisting and genre-busting acts. - Tony Clayton-Lea

Bartender! Danú, Féile na Bealtaine. Tigh Páidí Ó Sé, Ventry, Dingle

The goddess of fertility, whose name Danú appropriated, must be smiling on the group at the moment. With a superb new album and a slew of instruments between them that would normally populate a mini-orchestra, they've begun to reap the rewards of their diligent and endless touring in recent times.

Muireann Nic Amhlaoibh, although a relative latecomer to the group, has become an indispensable lynchpin, her voice, flute and whistle bestowing a certain filigree on Danú's already intricate instrumentation. Her voice whispers of a languid mix of world-weariness and sheer sensuality; her earthy tones bringing a gravitas to her imaginative song collection that suggests a singer far longer in the tooth than she is.

In the absence of charismatic founder member and piper Donnchadh Gough (laid low in Dungarvan with a broken leg), Donegal fiddler Oisín McAuley stepped nimbly centre-stage. He tackled everything from barn dances to polkas, slides and slow airs with his customary inventiveness, his fiddle a fine respecter of tradition yet infusing sacred tunes (borrowed from the likes of John Doherty and Vincent Broderick) with the odd impish curlicue that caught the audience unawares.

Danú's real strength is the ease with which they engage in ensemble-playing, each musician bringing a finely honed repertoire and none of them chasing the limelight. Tune sets are chosen not so much for their traditional compatibility as for their ability to ignite one another.

That's why Donnchadh Gough's bequest of The Peacock's Feather and The Copperplate and Micho Russell's The Boy in the Gap soared skywards so effortlessly, pristine arrangements picking the gemstones in each tune without a trace of ego in sight.

Young septets with one ear firmly cocked to the tradition and the other unapologetically towards the present might not be a rarity. But another of Danú's strengths is their often cerebral approach to the music, colouring and shading with the precision of perfectionists. That's why Bob Dylan's Farewell Angelina can sit so cosily alongside the divine Cailín Deas Crúite Na mBó, and why both sidle effortlessly alongside Bothy Band borrowings, Cape Breton tunes and Sligo reels.

The sum of such parts suggests a group whose future looks not only bright, but brimful of surprises. A spirit-raising concoction that'd buoy the dullest of spirits. - Siobhán Long

Ulster Orchestra/Philippe Nahon. Ulster Hall, Belfast

Frank Zappa - The Perfect Stranger. Naval Aviation in Art? Dupree's Paradise. Revised Music for Low Budget Orchestra. Envelopes. The Dog Breath Variations. Outrage at Valdez. Get Whitey. G-spot Tornado.

You Call That Music?, the title of this year's Sonorities Festival of Contemporary Music, derives from an experimental work by Frank Zappa, who, although he may not be the first name one would expect to find on an Ulster Orchestra programme, began life as a classical composer. The first records he bought himself were of Varèse and Stravinsky, and he later claimed that "the only reason I put a rock'n'roll band together is because I couldn't get anybody to play any of the chamber or orchestral music I had written as a teenager". In fact, Zappa sits in a well-established American tradition, exemplified by Ives and Cowell, of cultural fusion, the deliberate breaking down of the synthetic barriers that have been raised between music of different genres.

The three items which made up the first half of this concert were nevertheless disconcertingly orthodox. The Perfect Stranger contains good ideas - the warm string glissandi of the opening, for instance - but however busy the music gets, the modernist arrhythmia gives an impression of stasis and the piece functions primarily on the level of instrumental colour. There was more energy in Dupree's Paradise, a portrait of downtown Los Angeles in the early hours.

But it was the shorter pieces in the second half of the concert that best showed Zappa's inventiveness and sense of fun, although in some cases credit for the inventive sonorities should perhaps be shared with his regular collaborator, Ali Askin, who arranged them for the Ensemble Modern, Frankfurt. Witty, elegant, and earthy, the best pieces here, such as Revised Music for Low Budget Orchestra, achieved a fusion, and not merely an amalgam, of styles ranging from modernism to big-band jazz. It was all played with relish by the Ulster Orchestra under Philippe Nahon, a respected stalwart of the modernist scene. - Dermot Gault