I've never actually been in a "real" mastering studio--my only link to them being somewhere that I FedEX a CD to and a couple of weeks later get a CD back that sounds a whole heck of a lot better. I have seen many of photos of notable mastering facilities in the likes of Mix magazine and others that make me curious about one thing...

At the desk, there's usually an array of impressive gear, often including one LA-2A and one EQP1A. Considering those are mono, then why only one ?

My theory is that the only way to guarantee matched-pair processing of a stereo signal through such vintage mono gear would be to run two passes through the same units, one channel at a time. Did I guess right? :)

Sign me,
"Just Curious"