How do you like your improv jazz? Completely mental? Then SWIM Collective is for you. It’s unusual for contemporary free jazz to feature a vocalist; three vocalists even moreso. But this is the ensemble’s strength and USP: a highly theatrical, human sound. An accompanying band of harp, keyboard, cello, percussion and electronics allows for a diverse range of expression.

Some of the vocal improvisation is straight out of the Toronto Blessings of the 1990s, a flurry of impassioned tongues, over dissonant spreads of expressionist harp and piano cluster-chords. Sometimes the singers merely coo gently; sometimes they are silent.

One of the most fascinating things about these through-composed, non-repeating, freely improvised pieces, is how the style slowly (sometimes imperceptibly) weaves in and out of free-rhythm effects and anchored, rhythmic, tonal grooves. The whole ensemble are really listening to each other and giving each other space, never trying to dominate the sound. Sometimes this leads to moments of complete silence.

Audience participation is highly encouraged. Everyone is given some tissue paper, and a lucky few are given some spoons. Being conducted in and out, at different volume levels, the sound of paper rustling and spoons clinking en masse is quite mesmerising, and the chance to be involved feels pretty special.

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