Bonnie Choi launched her campaign against the 'archaic harpsichord' this week, refusing to accept stereotypes which burden her chosen instrument. Hong Kong-born Ms Choi, now performing and teaching in the US, displayed dazzling technique and drew new colours from an old instrument. Other artists might have started in the 17th century and worked towards a single piece from our own time. Ms Choi not only began with the most stunning contemporary work for her instrument, Ligeti's Continuum, she happily discarded musical evolution. Mixing old and new, outrageous dissonance, ragtime and conservative Bach, she dispelled any illusions about the restrictions of the harpsichord. Ms Choi played a reproduction of a 1745 harpsichord with three registers. No foot-pedals to change the timbre, but a number of knobs to change dynamics and hues. For Bach and Sweelink, this was sufficient. For modern works, Ms Choi created a whole thesaurus of sounds which I never knew existed for this instrument. Most interesting was William Penn's Fantasy. Not the amazing tocatta-like finger figurations which Ms Choi seemed to handle with ease, but glistening fountains of notes, hard percussion, arm's-length tone clusters. More subtle was William Bolcom's Graceful Ghost, originally for piano. I don't know if this was a special arrangement for harpsichord but this Joplin-like ragtime made it sound like a tin-pan alley piano. The opening 20th century work was the mesmerising Ligeti, almost banged out on the instrument. It took Royer's 1750s pieces to show the harpsichord in a multifarious garb: as fife and drums, lullaby and clown. A joyous performance. Bonnie Choi, harpsichord; City Hall Theatre, March 19