Few composers question themselves as profoundly as Mary Halvorson. It’s not self-doubt, but an endless curiosity of how patterns entwine. It’s one reason why she loves the Amaryllis band which she trusts to richly improvise on the shells she provides. But Halvorson also accedes she has a tendency to over-write. Like the plants she loves, she’ll write musical blocks that pleach together, several instruments playing all at once. When it works it’s a glorious gallimauphry of sounds.

But adding more saxes to About Ghosts brings a shift toward more expected formats, with the band occasionally playing in sections, stating themes and soloists launching off singly to explore those set ups. So, About Ghosts is a gnat’s crotchet more structured, losing the shades of surprise of earlier releases.

And with this denser soundscape, we hear less of Halvorson’s guitar. Her presence is ghostly, emphasised by her playing a pocket piano synthesiser, which brings background colour but little else. But Ghosts remains an impressive ensemble feat. ‘Carved From’, pocket synth and all, carries us away on a carousel of sound. The title track is as out as you can get in such a restrained context. And it includes one of those swoon’n’swoop solos we love Halvorson for. ‘Amaranthine’ likewise moves from a morse-code (well she is the Code Girl) drum/bass intro into a freewheeling set of improvs with Brennan all glister behind O’Farrill’s singing trumpet and Garchik’s soulful trombone.