XF 1.3 RSS feeds: Can you combine multiple board feeds into one?

I'd like to include RSS feeds from a selection of boards within the same forum, but it seems in Xenforo you can have all boards or one board in a feed and nothing in between.

Is this correct? Is there any native way to create one feed from a number of selected boards?

If not, what do other people use for this sort of thing? Pipes?