Flutist William Bennett, classical guitarist Simon Wynberg and harpsichordist Clifford Benson, Chamber Music Series

The ever-evolving chamber musical collaboration featuring combinations of keyboard, flute and guitar took another twist at the National Gallery when harpsichord was added to the mix last night.

The varied programme featuring pieces which ran from the ultra melodic to the downright angular and must have pleased most tastes. Flutist William Bennett and harpsichordist Clifford Benson began the evening with a Handel piece while guitarist Simon Wynberg sat out as the pair meshed together on two jaunty tunes sandwiched round the mournful adagio.

Ponce's Sonata for guitar and harpsichord was introduced as being written with "some wrong notes put in to add a crunchy quality".

Certainly the piece careered along in a jagged manner bringing to mind two old women having a well rehearsed argument, while the latter section borrowed heavily from 'God Rest Ye Merry Gentlemen'.

But those who found the piece a little jarring could take the opportunity to admire Wynberg's intriguing ten-string guitar which featured a slightly fatter fretboard while the bottom strings were added above the neck to be plucked openly. Flutist William Bennett introduced Couperin's 'Concert Royal Number Four in E Minor' with his customary humour, noting the piece had been written for 'King Louis The Umpteenth'.

He joked that the piece featured lots of twiddly bits, most of which they had to take out.

But when you are musician of the quality of Bennett, who has played with Yehudi Menuhin and the London Symphony, twiddly bits are not a major headache as he showed during seven splendid sections which veered from the regal to the romantic.

Benson's harpsichord was both light and rich and sometimes sounded not unlike a guitar as Bennett took the spotlight. Saving the best 'til last the second set featured some sublime moments such as Marin Marias' 'La Folia' featuring some soaring flute lines as Bennett cut loose.

But for me, 'Variations on a Theme of Mozart', performed by guitarist Wynberg, would have been worth the admission fee alone. It was described in the comprehensive programme notes as being achievable only by players with the highest technical and musical virtuosity.

It is written by Fernando Sor but I think they should have added an "e" to his name in memory of the many guitarists who must have worn their fingers red raw trying to master this musical obstacle course.

But while it is hard on the fingers it is certainly easy on the ears and I found myself almost purring with pleasure.

Taking a well-earned rest to a storm of applause Wynberg exited while the harpsichordist and flutist completed the advertised programme with Bach's 'Sonata in E Minor' which was also a delight.

During the encore all three musicians shared the stage for a brief French piece before taking their leave. But the musicians will be mixing and matching again tonight and tomorrow, no doubt with equally successful results.