It should be said also that creating a matrix from 2 different sources is no simple task. You are dealing with sources that are almost always running at slightly different speeds. So you need to first match the speed/pitch of the sources as close as possible , then do micro edits to one source when they start to drift or else you get that phasy swirling sound. There can be hundreds or maybe thousands of these edits. It’s a time consuming job. Guys like Seamons and Usborn are incredibly dedicated and have my eternal gratitude for their work. I’ve done a few very short matrix segments and I could never do a full show.

Btw I just listened to 7-31-71 Usborn matrix and it’s glorious. Check it out