All improvised music has a degree of risk but a duet is high-wire stuff, especially in this case, as each protagonist spends lengthy periods of time unaccompanied. Yet what jumps out from the opening bars of this session in Toronto, when both players were still in their youth, is the sheer power of the sound of each. At their peaks of intensity trombonist Bowie and saxophonist Lake are uncompromisingly volcanic, the bass splutter of the former and the altissimo shriek of the latter shattering silence around them. The ability of the players to construct elaborate narratives from the core of Lake's compositions, stretching the full harmonic possibilities of the themes, is also impressive. There are moments when they embark upon call and response with a kind of cat and mouse playfulness, as the big bad brass chases the wispy reed before the two land on gently singing terrain. Lake's writing, in any case, has an off-centre vitality that Bowie's bluesy brashness serves well, and the wide dynamic range of the music imparts a gravitas that compares favorably to similar megawatt intensity duos, an obvious example being Wadada Leo Smith and Anthony Braxton. This is music that is often fragmented, furrowed and fizzing with ideas, some of which are developed to their full extent, while others are probed and pushed into unforeseen directions.