The 26-year association of Brazilian tenor saxophonist Ivo Perelman and American pianist Matthew Shipp has led to the kind of advanced musical empathy that sets them apart from other duos. On this new work, their 14th together, there is a distinct sense of unforced communication between horn to keyboard, which produces music that is intuitive in character and mutative in structure.

Unlike the bulk of artists classified as avant-garde, Perelman-Shipp make a virtue of shorter pieces in which information can be both deeply concentrated and daringly spaced. Sometimes the players scramble into hyper-rhythmic activity, with each playing the kind of darting, choppy, nervy lines that bring momentum as well as exhilaration to the table, and when they really get going the barrage is quite something.

Yet Perelman and Shipp also hold the interest for their ability to veer off in apparently different harmonic directions, pushing a provocative clash of keys without totally breaking a sense of tonality. It is a valuable extension of the longstanding tradition in black music of blurring the line between what is deemed proper and what ain’t. Monk goes beyond as well as ‘round midnight in this case. There is nonetheless a barbed romanticism, a wry, twisted reverie in the resulting compositions, certainly with the airy sensuality of some of Perelman's lines, which wouldn't be out of place on an Ike Quebec session, as well as the liquid sensitivity of Shipp's motifs.

For the courage of their convictions and desire to stay a singular creative course Perelman and Shipp deserve much respect. This new journey in sound, by turns fascinating and challenging, makes that all the more clear.