Movie buffs know Howard Alden as the offscreen fingers of Emmett Ray in Sweet and Lowdown, Woody Allen's cod documentary about an apocryphal cheating, lying, self-obsessed jazz guitarist who treats women like dirt. "Type casting," mused Alden before playing I'll See You In My Dreams from the film. "People still ask me where they can get Emmett Ray CDs."

Actor Sean Penn, who played Ray, insisted on guitar lessons and Alden spent six months on them. "He was probably my best pupil. By sheer determination he learned a couple of tunes note by note." Alden himself must have been some teacher, for his seven-string technique last night was awesome.

Operating solo and with Simon Woolf and Steve Brown on bass and drums, he made masterly work of My Shining Hour (Harold Arlen), Dream Dancing (George Gershwin), 64 Bars on Wilshire (Barney Kessel), Tears (Django Reinhardt) and Jimmie Rowles's fiendishly difficult ballad The Peacocks. The more intensive his improvisation, the more devastating the stream of notes, the harder one had to strain to catch them.

Later, forced to pass London's worst busker (a wretch at Notting Hill Gate), I reflected on the sad fact that the less some guitarists know, the louder they play, while the more brilliantly an expert like Alden plays, the more silently he does it. Life is unfair.