Since the dawn of modernism – make that since the dawn of any activity that those involved were minded to label ‘music’ – most creative journeys have been concerned with defining ‘lots’. Notes, lots of them, and lots of surface activity held together with lots of deep structural underpinning. Even early minimalist pieces such as Terry Riley’s In C or La Monte Young’s The Well-Tuned Piano were actually about intensifying the materiality of music – lots of repeated notes, lots of structural engineering, lots of maximilist statements.

But working outside this usual new music narrative has been a lineage of composers, performers and thinkers who are interested in ‘nothing’. Cage’s 4'33" is to this negation of sound matter what The Laughing Cavalier is to Classical portraiture, and one of the musicians featured here, the trombonist, composer and improviser Radu Malfatti, was an early associate of the Wandelweiser network of composers and performers, whose aesthetic concerns spilt out of 4’33”. Malfatti is a gadfly spirit: he kicks Helmut Lachenmann in interviews for brown-nosing tradition and recently suggested that, when it comes to sounds, where they are placed is more important than what they are. Malfatti’s message seems clear: improvised and composed music have been trading off the same old same old textural splucks, blops, sucks, plops, blips and splops for too long, but the possibilities of structure are infinite.

Keith Rowe lays his guitar flat, plucking or bowing strings with one hand and manipulating electronics and radio signals with the other. He pioneered ‘table-top guitar’ back in the Sixties and, unlike Malfatti, remains smitten with texture and timbre. The symbolically titled ‘Ø’ finds them working out their aesthetic differences in compositions by themselves, by Cornelius Cardew and by Jürg Frey, before a 50-minute improvisation tests what they’ve learnt. Exact Dimension Without Insistence, by fellow Wandelweiser composer Jürg Frey, makes Malfatti’s point entirely. Enclosed by thundering silence, Malfatti plays cycles of three low Fs that Rowe answers with the G a ninth higher; there’s no content, only structure. But as Rowe rips into, disrupts in fact, Malfatti’s nonchalant, deadpan sustained tones in Cardew’s Solo With Accompaniment, a new sort of discourse opens; Pollock ’82, a graphic score, provokes the bloodiest encounter, with Rowe’s high-velocity but willowy muted sounds worrying the fabric of Malfatti’s playing. The improvisation is epic, the logicality of its temporal progress at telling odds with the inscrutable impulsiveness of the sounds…and the silences.