Beo festival: Martin Hayes/Micheal O Suilleabhain

The spectre of Sean O Riada hung like a Cheshire Cat over last week's Beo festival, and over this extraordinary highlight concert. Introduced by Iarla O Lionaird, Hayes and guitarist Dennis Cahill played a set I don't think anyone present will ever forget.

In recent times, Hayes has flung away the four-minute set of two or three tunes, and now jams together whole half-hour streels of jigs, reels, hornpipes, barndances, noddy ould polkas, switching time and tune on the whim of the moment. Sometimes, he momentarily wrong-foots Cahill, whose input is considerable, with his hanging, minimalist chords, jazz stabs, swing rhythms and rumbustious builds.

The tunes are so embellished, Hayes is essentially composing spontaneously, pushing a wave of emotion and memory in front of him. He starts off slow and dreamy to lock you into it; then ultimately working up, through all sorts of swivelling moods, to crazy-reel crescendos that blow the head clean off you.

It's an extraordinary synthesis of classical and jazz colouring, the Clare accent of his father P J, the uncle Paddy Canny, or pastiches of Stephane Grappelli and Eileen Ivors, particularly on that turbo-classical tune he calls P Joe's Pecurious Pachelbel Special.

The blood rushed more to the forebrain for O Suilleabhain, his grand piano backed by the Irish Sinfonia led by Kenneth Rice. They gave spirited renditions of O Suilleabhain's beautiful settings, like the hysteric Merrily Kiss the Quaker; or some of his own more moodful pieces, like Woodbrook; or the anxious string cascades of Oilean behind an unscored Niall Keegan, with his spectacular, growling, flutter-tongued fluting.

O Suilleabhain marshalled things along smartly, reading poems between numbers, like Seamus Heaney's one about Sean O Riada conducting the Ulster Orchestra like a cattle drover with an ash stick.

When O Lionaird was called on to sing Mna na hEireann, O Suilleabhain's ivories went into overkill, which was also a problem behind Sandra Joyce's beautiful cutting ornament on The Parting Glass. And while there was great manic spirit to O Suilleabhain's duet with Hayes on Eleanor Plunkett, it was a bit like throwing a meatball at a tennis racket.

But these are minor cavils. With his bustling brilliance, O Suilleabhain would charm anyone, and he and his entourage nicely topped a fabulous evening, full of deep emotion and hilarity.