Garfield would be appalled: it's Monday and I'm elated. The weekend was bedlam but today is a calm flow. Pottering, beers, Total Recall (my first viewing of the Arnie classic… that I can remember). Somewhere under an excited horizon a Supermoon is brewing. As the sun recedes it pops up like iridescent toast, or a big fizzing white berocca. Its beams are fire-bright as I walk out into the street.

Down a balmy road, round a blue-grey corner. Here, an elderly couple on the front verge: "We're looking at the moon. It's beautiful, isn't it?" I concur. There, a happy cat rolling around in a sandy patch, bathing in the glow. It's Monday! (From the Old English Mōnandæg ‘day of the moon’). Garfield would be appalled.

Here, the Rosemount Hotel. Some familiar faces floating in. In the mood-lit 459 bar, a trio comprising ZAC GRAFTON (bass), LENNY JACOBS (drums) and ALANA MACPHERSON rise to the stage. These musicians are all forces to be reckoned with, so it's a promising moment.

The set begins tentatively, with each performer feeling around for their sonic space, sending out radar notes to build a communal architecture of mood. The fascinating thing about truly "free" improvisation in a group context is that it almost never produces a consistent, or resolved, aesthetic. No matter how experienced the musicians, there will generally be moments of uncertainty where they sound each other out, trial-and-error towards an unspoken mutual understanding. Even veteran free-improv acts like The Necks have moments like these, and it's not a bad thing, it's just a stark deviation from conventional musical presentation. Showing your brush strokes. Performing your eraser swipes.

After a brief foray into arrhythmic "fusion" type sounds (owing to the chorus-wah bass) Grafton/Jacobs/MacPherson find themselves amid a simmering, droney intensity. Zac's extracting long, grainy, synth-like timbres in the low end, Alana's offering spasmodic howls and Lenny's tendering his distinctive, whip-crack interjections. It all builds, grows stronger like a four-wheel drive gaining traction in the mud, and swells to a thunderous climax. Saxophone roar, bass boom. Lenny Jacob's drum sticks rain down on skins and cymbals like heavy hunks of hail. He slices at his high hat from a great height, like he's furiously swinging his axe to chop some stubborn, hissing, shimmering timber. This first improvisation collapses happily under its own tremendous weight. Their second excursion is a kind of smouldering denouement, understated bass polyphony anchoring sax twinkle, cymbal sigh, metal chain jangle. There's no need to explore too aggressively now. It's more of a languid wandering around.

Next is AKIOKA, who provides the perfect second instalment. The wild business of the previous trio is now handsomely counterposed against Tessa Darcey's measured, slow motion vocal extemporisations. What begins as a minimal, seemingly spiritual chant is soon layered to become an evocative swirl of melodies, noises and tones. But it happens so gradually it's almost imperceptible, like you're an ant walking along a Rothko. Things get a little more choppy and radical towards the set's close, with beat-repeat weirdness and loop channel crossfades creating a more dynamic landscape. But it all ends on a single, serene vocal note, which well summarises the tranquility of the performance.

Finally we hear from MARK CAIN, who's something of a local legend, performing across jazz, experimental and global folk genres since the '80s. He also an avid builder and inventor of instruments, creating musical tools out of PVC pipe and other commonplace materials. Tonight we get to hear some of these home-made innovations, as well as saxophone and other more conventional wind instruments. Mark performs short improvised bursts, swapping to a different weapon of choice between each. The music itself is less impassioned, or perhaps less embodied, than in the previous sets - it all feels very casual and nonchalant, almost more demonstrative of a process than expressive of a mood. In any case, the improvisations are expertly delivered and tastefully paced, oscillating between dense note-flurry and slow, expansive tones. Arguably the most compelling thing here is the quick switching between instruments and therefore timbres, the same breath running through ostensibly similar tubes to produce vastly different results. There's a kind of pseudo-oboe, and a rudimentary flute controlled by hand modulations over the tail end. Most whimsically, a set of bagpipes in which the bag is a rubber glove that inflates prior to each droning experiment. It's a wild parade of variables.  

The music wraps up but performers and peers linger, chatting about projects and ideas and possibilities. More than a recital, a night like this feels like an open-ended gathering of like-minded people, creating a node to punctuate mingling musical journeys. I begin the walk home, drinking in the moon again. Every sound I hear seems alive, brimming with potential.