The cover artwork sees Urcola and D'Rivera back-to-back, trumpet and clarinet raised a la pistols at dawn. The gauntlet, we're told, was thrown down by Urcola, who challenged his long-time collaborator to record a piano-less quartet project, so opening up possibilities for directness of sound and increased ensemble interplay – along with exposing flaws, vulnerabilities and notions ill-conceived and misguided. Having presented a live musical tribute to Gerry Mulligan's quartet with Chet Baker, Urcola was keen to push D'Rivera to his improvisational edge, aided by regular drummer Doob and young Kiwi bass player Smith.

The results are rejuvenating: denied recourse to explicit harmony, and gifted a varied repertoire of work by the likes of Ornette Coleman (‘Una Nuy Bonita’, all linking horns and driving bass) and Thelonious Monk (‘Bye-Ya’, as interpreted by trumpeter/conguero Jerry Gonzalez), the players palpably revel in finding melodic footholds, in flexing their creativity. Urcola's arrangements cherry pick from tango, Latin jazz, Afro-Cuban rhythms and a Wayne Shorter suite, while a reduction of a big band treatment of Dizzy Gillespie's ‘Con Alma’ finds D'Rivera on alto sax and shout choruses a plenty. Trumpet and clarinet face off to lustrous effect on Richard Nant's ‘Leyenda’, in a track – an album – with two formidable victors.