It is impossible not to enjoy the work of saxophonist Gilad Atzmon. He has astonishing technique and great emotional depth. But his latest musical venture and album, Artie Fishel and the Promised Band (pictured), presents a conundrum, even a contradiction. Atzmon is known for his politics, and his sharp satirical jokes from the stage are always delightful. But the assumption of an alter-ego in the shape of Artie Fishel, a Jewish musician convinced that the roots of jazz lie in the ghettos of Eastern Europe, or as at the Spin last week, in the cellars of Golders Green, allows Atzmon to shift from a musician with a great line in humour to a stand-up comedian with a great line in jazz.

Thus a large part of the first set was taken up with Atzmon at the microphone adlibbing with the wit of a professional comedian and filling the Spin with waves of laughter. It is a measure of his intelligence that he can make a joke out of Chomsky, Nietzsche and paedophilia without veering into buffoonery or bad taste. The humour was broken up by Atzmon's characteristic driving alto sax in which, as if to prove the theories of his alter ego, he mixed Jewish melodies with jazz standards and in his solos quoted from so many other jazz tunes that by the time a solo was picked up by John Turville on Fender Rhodes the original melody was long lost.

There can be no doubting the power of Atzmon's playing and the fluent wit with which he took us on a tour of so many of the great tunes from the book of jazz standards. Also the rest of the band were tight and imaginative. He dropped the wig and dark glasses in the second set, but could not resist a further tranche of humour, including some wonderful remarks on beboyp' followed by a typically wild rendering of Night in Tunisia. Although the band and the audience were evidently enjoying themselves there was a feeling that the music was subservient to the humour and it was only with the second encore that Atzmon put jazz first to play I can't get started with palpable intensity and sincerity. Up to then it had been brilliant showmanship.