The twin 57, the first for recording, the seconD for PA. I didn't want to risk a splitter. In regards to the speakers they were paralleled. This is a speaker wiring technique that I've used for years. Some years back I had a lot of success with a pair of Auratones strapped in parallel to a pair of Radioshack speakers. That's the rig I used for the making of Peter Gabriel's So album.