German string quartet Sonar meet renowned soprano Juliet Fraser in a concert of ambiguous meaning and definite feeling. Naomi Pinnock and Heinz Holliger are artists bonded by their open-ended style – both of them leave definitive impressions through sparse music, the kind that hovers over its listener indefinitely. Rather than fill the space completely, they open it up, giving each listener the chance to place themselves within the sounds. A founding member of the radical EXAUDI ensemble, Juliet Fraser lends the perfect voice to Pinnock and Holliger, colouring their ambiguous work with her own expressions. Along with Sonar, she becomes wrapped up in the pieces, experiencing them on the same immersive level as the listener.