In their duo concerts, Mal Waldron and Steve Lacy trod a fine line between the interpretation of Thelonious Monk’s music, true to its melodic and metrical structure, and far freer fare. This Antwerp event, planned to celebrate Mal’s 70th birthday (which occurred the previous month), finds them charting a similar course in an all-star quartet format.

A brief and beautiful rendition of ‘Epistrophy’ sits at the artistic core of the album (released on vinyl for Record Store Day and CD thereafter) and there’s an almost 13 minute version of ‘Monk’s Dream’ that’s notable for a dazzlingly brilliant drum solo from Andrew Cyrille which manages to keep the theme in our minds percussively, throughout his variations, until an anguished grunt or scream from the drum stool, and a recap of the introductory rhythm, brings the band back in.

Linking the two Monk interpretations is Steve Lacy’s ‘Longing’ which is a free-form piece, but it seems an absolutely logical extension of the thinking behind the quartet’s treatment of Monk. Reggie Workman’s ‘Variation of III’ is the most abstract piece here, with an arco solo ushering in the others by turns, with some fine soprano from Lacy. The set is book-ended by Waldron’s compositions, and the closing ‘Snake Out’ – a forceful low register piano theme that leads into a tumbling piano and soprano head – is intertwined with Mal’s ‘Variations on a Theme by Cecil Taylor’ containing a long, pensive and beautiful unaccompanied piano solo that must rank as some of the finest late-period Waldron on record. Congratulations to Zev Feldman for a characteristically thorough, first-rate production and to Barney Wilen’s son Patrick for preserving the tapes.