Ambulance featuring Eddie Henderson, Ronnie Scott's, London

Live and unplugged, just as it should be

"Oh dear, sorry about that. Looks like the server's gone down. We won't be able to check our emails either. That's a shame." It's not recorded whether Charlie Parker ever addressed his audience like this but we can be fairly confident he didn't. Yet it's the kind of mucky talk increasingly to be heard on jazz stages, where boffins disguised as sidemen habitually squat and fiddle with laptops and, not infrequently, the sodding server goes down.

It wasn't clear what the server should have been adding to Ambulance's interpretation of Herbie Hancock's "One-Finger Snap", but it hardly mattered. Saxophonist Rob Townsend was merely compelled to play a solo on mouse-finger and knotted brow, while the rest of them vamped tastily.

Ambulance are an aggressively upcoming quintet, led by bassist Arnie Somogyi and abetted, for the duration of this residency at least, by the American trumpeter Eddie Henderson. The group are young-ish, muscular, oblique and witty. They are Britishly programmatic, cleverly postmodern and they abjure anything so dull as conventional bop changes, except in emergency. Which made Henderson's integration into their fold all the more impressive.

Henderson is nothing if not a smooth operator - check out the caramel suit, black poloneck and polished dome. It was a tribute to his natural modesty and the robustness of the group identity that the evening at no stage felt like a concerto for Eddie. Instead, saxophonists Townsend and Paul Booth, drummer Dave Smith and pianist Tim Lapthorn took turns to impress their leader, who conveyed his pleasure with matey grins.

"Captain Courageous", the piece which gripped most tightly, begins with squelches, then snaps like forestays in a blow, pitches, yaws, passes through a narrow strait in which Horace Silver wrestles Augustus Pablo for the helm, and then devolves into the groggy metre of a shanty. Time stops, time starts, there are more squelches and slooshes. The captain ploughs on regardless. And they finished with a piece in 13 called "Tim's Delight", in deference to pianist Lapthorn's evident unease in this most halt of time signatures. Eddie Henderson just slipped into it as if the piece were a favourite pair of pyjamas.