Not only does this documentary let you see extraordinary music being made back then, including Gregor Nicholas' hypnotic 1984 filming of Drum/Sing, but Dadson's partners-in-percussion fill in the history. McGlashan talks about creating structure through rhythm, explaining how each player's relatively straightforward patterns overlapped, making it seem a lot more complicated.
Looking at earlier partnerships, Dadson appreciates "the symbiotic influence from being with such talented collaborators ... I've always been touched by people who have taken on the language that I'd initiated and then added something of themselves to it".
Philip Dadson: Sonics From Scratch reels through the decades, from archival footage of Cornelius Cardew's London Scratch Orchestra in the 70s to Dadson, just last year, leading a group of sonic adventurers to make their own music among the protected birdlife of Tiritiri Matangi. He confesses to feeling "embedded in Nature" and the Tiritiri Matangi project transferred feelings into actions.
Over the past few decades, Dadson has devoted much time to building his own extraordinary and sometimes eccentric instruments. He is a charismatic performer on them, as you can see on screen. The sound sources might be as simple and primal as river stones tapped together, or ingenious and bizarre noise-makers that could find a place in an Inspector Gadget line-up.
If you want to experience this singular soundworld, exquisitely recorded, search out his 2004 Atoll CD, Sound Tracks, and hear what magic can be drawn out of the gloopdrum, zitherum, nundrum and ostifans. Dadson is particularly proud of a mask-like structure that has him looking a little like a cardboarded Ned Kelly; it is in fact, he says, a headbox guitar.
Inspiration comes from all over. In the beginning there was Cornelius Cardew's love of found and home-made instruments. Later there would be that chance encounter with a Solomon Islands group at a South Pacific Arts Festival; the bamboo beats under its songs would inspire From Scratch's PVC pipes.
Despite the wealth of material on screen in Ogston and Stewart's movie, and authoritative commentary from the likes of Wystan Curnow, Christina Barton and Andrew Clifford, Dadson's rambling piano solo over the opening titles raises questions left unanswered.
I am reminded of his spikey, post-Bop keyboard improv on Fly me to the Moon played on half-a-dozen distressed instruments, undertaken for a 2000 Christchurch show, Piano Forte.
It turns out that the young Dadson was taught piano by the wife of one of his father's colleagues in Napier's Frivolity Minstrels. "She was very good at playing Winifred Atwell," Dadson remembers. "And it was learning those boogies that got me interested in jazz."
Revisiting From Scratch's 1981 Pacific 3,2,1, Zero in the new documentary, perhaps you will find yourself detecting just a trace of Atwell's funky boogie lurking in the ruffled sonic ocean.
What: Philip Dadson: Sonics From Scratch
Where and when: Academy Cinema, today at 3.45pm; Sunday 4pm; Thursday 1.30pm
