Bristol-based double bass player Dominic Lash has a been a steadfast and scholarly figure in the UK improvised music community for around 15 years, since his days as a youthful lightning rod on the fertile Oxford scene. His early band, Convergence Quartet, owed much to the playful seriousness of Anthony Braxton and, indeed, two members of that unit – pianist Alexander Hawkins and cornetist Taylor Ho Bynum – have worked with Professor Braxton. So it's little surprise that these first three releases on Lash's new Spoonhunt label – all recorded live at Cafe OTO – display a similarly cerebral preoccupation with ludic strategies.

Lash's eponymous quartet revolves around Alex Ward's taut and spidery electric guitar and Ricardo Tejero's vinegary alto sax, which combine to create a tense, hyperactive energy, while the group pings from idea to idea like a gang of Adderall-fuelled teen geniuses. Recorded as one continuous suite (plus encore), the music veers from thrashing avant-rock, through furious free-boil, to stately, spacious drone powered by low arco drag. ‘Dactyloscopy’ takes an almost tongue-in-cheek turn towards jazz, with Lash tucking into a walking bassline, Ward dealing nifty harmonics and drummer Javier Carmona offering an implied swing – but it soon mutates into a bobbing strut that's harder to pin down. Meanwhile, pieces like ‘Isthmus’ are more concerned with texture, piling up jagged chords while Tejero's alto approximates John Butcher's throaty gurgle.

Butcher himself is on hand in quite a different quartet, featuring fellow improv veterans, drummer Mark Sanders and the late guitarist John Russell. Here, the energy is more measured, settling comfortably into the kind of unhurried, long-form improvisation that used to be called non-idiomatic before it became so familiar. Beginning with a tentative and suspenseful flutter of woody scrapes, ringing strings and rumbling gongs, there's purpose from the start. Russell's dry scrabblings are unmistakable as he mirrors Butcher's more dominant sax trills and, later, finds room for brittle harmonics while Lash creaks and sighs like a becalmed galleon. There's a sense of focused restraint throughout: even when the sounds build to a dense and furious roar, it only lasts for a brief moment before control takes over.

The 20-piece Consorts ensemble is an even more rigorous proposition: a single, 46-minute work that, according to Lash's notes, explores ‘the possibilities of combining sustained-tone music, improvisation (both guided and free), and the relationship between acoustic and amplified sound.‘ Utilising electronics, strings and wind instruments (as well as an amplified kitchen sink), Lash deftly guides this large group through a thick cloud of low-end drones and harmonics that moves with implacable calm towards a conclusion that's both inevitable and highly satisfying.