KEY POINTS:
A little over a week ago, John Williams was performing Takemitsu and Sculthorpe concertos with the Melbourne Symphony Orchestra; on Saturday, he will be in Auckland playing duo with fellow guitarist John Etheridge.
The Australian-born Williams has been collaborating with other guitarists since the early days, alongside Julian Bream in the 1960s. "A guitar duo is a really fantastic thing," he says. "Trios and quartets are not so good as you start to lose the colour and the personalities of the different strings and instruments."
Here is a man who appreciates the collegiality of his fellow musicians.
Williams was involved in setting up the cross-over band Sky in 1979. "There were so many musicians rubbing shoulders with one another in London," he says.
"You'd simply meet other people and find a way of making music. Sky was described as cross-over and fusion but these weren't our terms. We just did what we wanted to do together."
Bigger issues are raised. "Classical training is a very limited one. The problem is that it sees itself as some sort of superior art form, better than any other kind of music.
"When you have experienced blues, jazz or even world music, for want of a better word, you realise that classical music is just one very wonderful discipline but they are all equal in terms of musical expression."
His new partner, John Etheridge, comes from other spheres, having played with the likes of Soft Machine and Stephane Grappelli. Williams had heard him in various groups around London and Etheridge was invited to join the 2002 Magic Box project.
"Steel strings were very suited to the sound of the African music we were doing," Williams explains, "and I decided then and there that John was the bloke to do it.
"These days we play to each other's strengths. I don't try to improvise and he doesn't try to play the classical. We simply use the different colours that are available to us."
Williams' explanations of the two men's working methods is fascinating. A piece like Extra Time, which opens their recent Places Between CD, sets off with a Bach Prelude, but there are also sections of organised spontaneity which provide space for Etheridge to offer his elaborations on the material.
The Australian's intense love of African music is still very much to the fore. "Rhythm is the pulse of life in African music," he explains. "European music can be very boring alongside it; our marches, minuets and songs can be pretty basic compared with African or South American music.
"I am also drawn to the slow pace of the harmony. Europeans are used to harmony being the king and the key to what interest the music has. This has its limits and is why I like Peter Sculthorpe's music with its slow rate of harmonic change - there may be less harmonic variety but it is more complicated in other ways."
The Australian composer is just one of many names which cross through our conversation. Another is the Cameroonian composer Francis Bebey, whose Sangara, an infectious markossa dance, will open Saturday's concert in a version that will be "much faster" than the one on the Places Between album.
John Williams is a man with a commitment to composers who are too easily overlooked. The inclusion of a piece by Augustin Barrios on Places Between reflects his admiration for a fine Venezuelan guitarist-composer who was "spurned by Segovia, even forbidding his pupils to play Barrios' music".
And there will be fresh discoveries for many on Saturday night.
If the reviews from across the Tasman are any indication, the greatest revelations may come from either Etheridge's original Monti's Casino or Ben Verdery's Peace, Love and Guitars, the title of which is a pretty nifty summation of what the music of this partnership is all about.