The good people at Raukatauri had no difficulty finding a family happy to talk to me about the work they were doing: Grant and Sparrow Jackson, a North Shore couple who have been bringing their son, Jesse, for almost four years.
Jesse, 13, who is severely autistic, doesn't communicate verbally. But music is another matter. He arrived for his session last Friday, as the pre-storm mugginess gathered, almost bursting with excitement. He had eyes only for Claire Molyneux, the therapist who works with him weekly. He virtually dragged her into the room, stocked with piano, guitar, drums and various percussion instruments, where they were to work.
Grant and I sat in another room and watched a video feed on which we saw Claire dealing with what was plainly a restive young man. She played phrases on the piano, or tapped out rhythms and waited for him to respond. He became noticeably calmer, though things turned to custard a little later.
"He's acting up a bit today," said Grant. "He knows something's up with you being here. And the weather has an effect, too. People say I'm crazy, but this air feels very heavy to him."
Yet Grant is very clear that the therapy has made a huge difference to Jesse.
"When he first started he would do everything through the therapist. Now he is a lot more independent and makes his own decisions."
Earlier, Claire, who is head of clinical services at the centre, had explained to me that music therapy is tailored to a client's specific needs. Someone with a physical handicap will need to improve motor skills but Jesse's needs are more complex. To make music, he needs to concentrate, to make eye contact, to take turns, to listen, to wait, to respond: these are the same skills he needs to practise in the world.
"Other therapies tend to target a deficit," Claire explains. "A speech language therapist will target speech deficits; a physiotherapist physical deficit and so on. In music, we focus immediately on the person's strengths."
Music, she said, is ideal because "it doesn't rely on words or depend on a cognitive ability. Music is such an innate form of expression across all cultures, and when we can communicate through music, it is on another level."
Sparrow Jackson says that music therapy gives Jesse "a relationship in which he has a sense of self".
"We've tried all sorts of therapies and this is the only one in which we, as parents, feel a sense of worth and belonging. And for him it is a very safe place to be emotional and let it out. He loves it."
Later, I watch a video clip of a session with a severely disabled child of only 18 months. He cannot sit erect; his mum holds him upright as therapist Marie Willis plays and sings a line from Twinkle, Twinkle, Little Star. With agonising effort, the child, whose motor control is virtually nil, swipes a set of chimes in front of him. It is the response signal that will prompt Marie to play another line. It's sometimes a long time coming - but it comes.
Watching it, I struggle to hold back the tears that are a mixture of empathy and vicarious despair. I try to remember that where I see disability, mother and therapist are seeing achievement.
"I come back to the word celebration," says Marie. "The work is predominantly about celebrating what he can do - and the family gets to keep a record of what he has done."
On the web
www.rmtc.org.nz