JOHN Williams is one of the most popular guitarists of our time. His name alone, I suspect, would have been sufficient to yield a full house for the last of the National Concert Hall/The Irish Times celebrity concerts on Saturday. But what a listener takes away from a concert has as much to do with what is played as who plays it. And the programme of "Guitar Duets from Around the World" chosen by Williams and his fellow Australian partner, Timothy Kain, was on this occasion a disappointing one.

Arrangements accounted for the bulk of what was on offer. The most successful were in the familiar Spanish ambit of Granados, Albeniz, Falla. For me, it was the sixth of Granados's Spanish Dances which provided the greatest pleasure the piano original, after all, was written in imitation of the strumming of the guitar. Less successful We the arrangements of Carolan, Soler and Rossini, all of which seemed to sweeten and blunt the originals.

The rest of the programme was given over to works by contemporary composers, Philip Houghton, Nigel West lake, Leo Brouwer, Benjamin Verdery, Peter Madlern, Frederic Hand, Paulo Bellinati.

The Cuban Leo Brouwer is the best known figure here, and it was his short set of Micropiezas which demonstrated the finest balance of invention, imagination and duration. Elsewhere the challenges seemed more directed at the performers than the listeners and it may be that the rewards were similarly allocated. The closer the pieces came to the style of pop ballads, the more both audience and players seemed to warm to them.

The playing throughout the evening was svelte and accomplished, matching well the "easy listening" characteristics of the programme itself.