If you want to see and hear our choir, as well as seeing some lovely shots of the cathedral interior, this video link from Radio Canada should be available for at least a week. The narration is in French. Not sure if it will stream for viewers outside Canada. You can also try another link, to the French TV transmission of the same thing, but with a different intro.
You might want to start at the 4:40 mark on the Radio Canada video - that's the first hymn - and then go to 11:45 for the Ralph Vaughn Williams Te Deum.