I used to find trying to ignore Glenn Gould’s humming while listening to him play the piano annoying, but at some point it became a part of the performance. Now I can listen to the entire Well Tempered Clavier and not notice the vocal accompaniment; I would probably miss it. What is less easy to overlook is Gould’s cut and paste approach to recording; he used to splice different performances together to make what – to his mind – was a result that was closer to perfection. This wasn’t very noticeable on the old vinyl versions of his records, but the newer digital offerings make the splices very plain – and disconcerting.

Nevertheless, Gould was a great pianist and, in particular, a great exponent of J. S. Bach; he is one of Canada’s national treasures. He was also very eccentric. For example, he took great delight in constructing improbable theories about the virtues of Petula Clark’s singing; he liked to conduct an imaginary orchestra while playing and he insisted on sitting on a butchered kitchen chair made by his father – and there was the humming. He had strange ideas about the inner heartbeat of a piece of music; he applied the theory to the tempos of the sections of the Goldberg Variations; it never made much sense to me, but there is something about his interpretation that is compelling.

When he was 31 he gave up concert performances to concentrate on studio recordings; for a lesser musician this would have signalled the end of a career, but not for Gould. Tragically, he died in 1982 aged 50.

There is a new film about him that suggests that the eccentricity was to some extent manufactured; I very rarely go to the cinema, but I might go to see this:

Canadian pianist Glenn Gould is a man of endless fascination, at least to Canadian filmmakers. Genius Within, a new documentary, is the 18th film about Gould, ranging from early looks at the piano prodigy to the feature film Thirty Two Short Films About Glenn Gould, which divided his life into movements, like the Goldberg Variations, and put them on the screen as a sort of mosaic portrait of an eccentric and troubled man.

The eccentricity is part of the fascination. “Ultimately there’s a mystery at the heart of Glenn Gould,” philosopher Mark Kingwell says in Genius Within, and it is a mystery that even new revelations about Gould’s love life cannot entirely dispel. Genius Within is the first film made since it was learned that, as someone says in the film, “his dark secret” was that he had normal relations with women.

The movie, directed by documentary veterans Michele Hozer and Peter Raymont, takes us on a familiar but lively trip through Gould’s life, using interviews and old footage — of which there is an awful lot — to get us up to speed on the life of this mythical genius, an icon, as someone says, on the order of James Dean.

Here he is at his best playing the sublime opening Aria of the Goldberg Variations: