Daunik Lazro / Joëlle Léandre: Hasparren

Whether one rates a free improv album or not can be notoriously subjective, depending as much on the listener's mood as any musical attribute. So when a recital comes along by two of France's most adventurous musicians where everything seems to just click, it's worth teasing out what makes it such a success. Let's be clear, it's not background music. To get the most from it requires some concentration. Perhaps headphones. That way the near perfect interaction between Daunik Lazro's supple baritone saxophone and Joëlle Léandre's virtuoso bass fizzes between the ears, sparking synapses as it goes.

It helps that they share such an extensive history, meaning that they are well aware of each other's capabilities, and perform accordingly. Their first documented meeting was in 1983 on the reedman's Sweet Zee (Hat Art, 2010), with a series of further encounters over the intervening years. However Hasparren is their first recording just as a duo. Being so well established on the European scene, neither feels the need to flaunt their undoubted chops. In fact Lazro's sustained phrases on the opening cut are a stunningly simple but nonetheless effective foil for Léandre's fluent sawing.

Though there is a clear lower register affinity between the two instrumentalists, both are so adept at stretching the putative ranges of their instruments that there's no need to worry about a narrow sound spectrum. Of course each demonstrates peerless control. Lazro's split tones and dog-bothering whistles at the start of "Hasparren IV" are artfully restrained yet edgy, while Léandre 's extended technique remains as marvellous as ever. Their choices of how closely to follow and when to oppose have a feel of inevitability.

As befits experienced improvisers both possess an innate sense of how to structure on the fly. Léandre does so most obviously on the unaccompanied "Hasparren V" where a bow bouncing introductory figure recurs as a motif throughout the piece, contrasting with an expressive sequence of slurred notes and singing lines exploiting the bass' harmonics, before ushering in the poised final reiteration. Spontaneous allusions to melody and rhythm surface periodically, hinting at links to wider traditions. In the end it's all about intense listening and apparently effortless communication between two distinctive individual voices which combine to convey tremendous emotional depth.