As mentioned in another thread, I recently bought the first Spotlight Collection of the great Tom and Jerry MGM cartoons from the 1940s and 1950s. One question, some of the cartoons, especially from the early 1950s, are identified as being recorded with the Westrex system and being in Perspecta Sound, the directional panned sound process. (Other, including the stereo Touche Pussycat, are identified as Western Electric recordings-is that the longer version of Westrex?) But on the DVD, they're straight mono. I know the original prints were destroyed in a fire, but were they originally shown with directional sound?
A lot of MGM stuff had the Perspecta logo in those days, even shorts (filmed). Don't know why, the stuff wasn't released in stereo. I think for a while it was just a trade name for MGM like "Vitaphone" for WB. I have seen many Tom & Jerrys from that era from original 35 prints and they are all mono. None have any tones on them at all. So, either a few prints were done that way and the rest mono or none. I can't really stand the cartoons from that era so I have not studied it but I've seen many original IB Tech prints and they are all mono even with the Perspecta logo in the credits.