There was not a dull moment in the concluding concert of the Now and Then series at the Irish Museum of Modern Art last Sunday afternoon. The British group Gemini plus Maya Homburger (baroque violin), Evan Parker (saxophones), Maggie Nicols (voice) and Barry Guy (double bass), played compositions by Barry Guy and free improvisations.

Evan Parker's improvisation on soprano saxophone was a dazzling cascade of variations on tiny motifs, using circular breathing and - incredibly - simultaneous polyphonies of high and low pitches. The two group improvisations were for double bass and tenor saxophone, and the same combination plus voice. They responded to one another at lightning speed, as the lead was taken by one player then another! Free in form but incremental in nature, they looked as good as the sounded.

Barry Guy's compositions for tape and solo instrument drew on non-Western folk music. Whistle and Flute featured Gemini's flautist Will Sleath, and is based on the Turkish Bozlack. Ceremony for baroque violin and seven-track tape is based on Navajo chant. In both works, the pre-recorded tape sounds are similar to or created by the solo instrument. Yet the soloist was always evident as such; and in Ceremony in particular, evocative expression was personalised by improvisatory elements.

The concert began and ended with Barry Guy's Bird Gong Game. The title's double-take on ornithological music conveys the atmosphere. The composer directed the length, combination and sequence of events; improvisation is controlled by given material; and there is the extra edge of a soloist (saxophone first, voice second) having his or her own way - or not. The second hearing, and the short third version played as an encore with voice and saxophone soloists, were utterly different, yet familiar.