I Recently purchased a 2 disc Venus & Mars acetate cut by George Peckham at the Master Room studios in London England. The discs are actually 14” dub plates. They would produce the record stamper from these dub plates and then press the records. Once you make a stamper the process destroys the dub plate.
Not sure why these dub plates were not used to make the stampers but I did get a chance to listen to both discs and to me the songs seem less compressed than the official release. Great sound. I wonder if Paul did not approve this mix and had the sun plates redone with the compressed versions?
The dead wax is hand etched Paul McCartney & Wings and George Peckham’s signature A Porky Prime Cut. The acetates came in a metal container with Master Room stickers on the lid.