Here’s a link to the paper…
Fairly short, well written and understandable. It provides a straight forward approach to determining mic angles and spacing for ideal spatial playback based on just a few considerations.
I carry it around in my mobile rig case all the time. There’s a web site out there…I think it’s something like “singpeil” or something like that that has a pretty neat web browser application that lets you plug in various mic angles and spacing and such and it’ll show you the stereo recording angle that will be produced. Makes more sense once you’ve read the paper and see the web site. I’ll try to find that link again…been awhile since I used it but it’s pretty cool.
BTW…I should correct myself on one thing, I said that this lets you calculate a setup for an x/y pair. More accurately, it’s more of a hybrid of a near coincident pair in an x/y configuration.
Here’s a link to a good (though very technical) web site that discusses it. It also has links to the site I was referring to… look for the links to “Image assistant 2.0” and “Hauptmikrofon.de” just into the first page.
All the best,
Karl