I just posted a detailed description of the Canadian copyright rules on my Blog. Basically, any performance (record) published 1964 and earlier, and whose music creator(s) passed away 1971 and earlier, is in the public domain.
There's some vintage jazz that falls into that category. Most acoustical records, and a fair number of 1920s and 1930s electrical era records as well. So I plan on doing some jazz at the very least.
The nice thing about classical music (nice in the public domain context at least) is that since most composers (except modernists) passed away quite a while ago, all their music is in the public domain. That means that there are a large number of classical records from the early 1960s and the 1950s that sound great, and are free to use for any purpose in Canada. So we'll be playing quite a bit of classical, opera and vocal in our programming.
The challenge is that many of the pieces are quite long, so don't fit nicely into predetermined programming slots.
I would like to do some drama works as well. Book readings are an option, as is OTR. However, there's a catch with OTR in Canada. Unlike the U.S., where copyright had to be registered with the Library of Congress for quite a while (and most OTR wasn't), in Canada, copyright was automatically assigned once the work is created. Typically, for something like OTR it would be the scriptwriter. The performance rights would be complicated, but since all the OTR I would be interested in were performed 1964 and prior, the performances would be in the public domain anyway.
So technically, OTR whose scriptwriters passed away in 1971 or prior should be in the public domain. Of course, this would be for scripted shows only, such as The Lone Ranger, The Shadow, etc.
A big issue, however, is that quite often, the scriptwriters are unknown. There are some OTR sites that publish some information, and I've done some exercises in the past of going through and determining which episodes of some shows (on a very few shows) are in the public domain. But it's a big pain.
Then there's the "Rule of the Shorter Term" in the Geneva convention. It states that if a work goes out of copyright in its home country, then it goes out of copyright in all countries observing that rule. Canada observes it. But the CUSMA trade convention prevents it being used for the U.S. If CUSMA goes away, as it is being threatened, then OTR (most of it, scripted anyway) in the public domain in the U.S. would automatically be in the public domain in Canada.
Finally, we still plan on having 4 x 6 hour blocks of programming. Some slots, like vintage jazz, will be randomized playlists, while others will be rotation files with predetermined music and/or shows.