Does humour belong in music? Italian musicians Stefano Bollani and Enrico Rava would probably think it a silly question, since humour and good- humoured musicality infuse everything they play. Lengthy duo improvisations are not always a barrel of laughs, but Bollani's technical command of every jazz piano style, together with Rava's warm and fluent trumpet, keeps the audience smiling. And occasionally gasping in admiration. Their repertoire embraces Nino Rota and Jobim, and ends with a number dedicated to Chaplin, its pathos and sweetness leavened by a breakneck finale. On standards such as Cheek to Cheek, Rava plays from right inside the tune, while Bollani throws in everything from flamboyant neo- classical flourishes to comedy avant-garde, and even a bit of "air piano".

The Tord Gustavsen Trio seem to be pedalling on air at times, but not for comedic effect. Their contemplative music has commercial appeal - like a slowed-down, postmodern Ramsey Lewis. There are moments when they seem to be competing to play the least number of notes as quietly as possible - a bit like a slow bicycle race - and you could feel the bass drum, more than hear it.

Belgian pianist Jef Neve is halfway between Bollani and Gustavsen, emotionally and geographically. Working in a close-knit team with drummer Teun Verbruggen (also in the Flat Earth Society) and bassist Piet Verbist, there are similarities to the Esbjörn Svensson Trio in their use of orchestral dynamics and rock theatrics. Second Love builds from a ruminative opening to a relentless, rolling pattern that recalls EST at their bombastic best. There is humour, too, in titles such as A Waterfall Never Comes Alone and Nothing But a Casablanca Turtle Slideshow Dinner.

· The London jazz festival continues until Sunday. londonjazzfestival.org.uk