I love how they were still using the "Orthophonic" term in 1960. That dates back to the late '20s when RCA pioneered the electrical recording process. The Orthophonic record labels showed up in 1927, but the first Orthophonic recordings were made in 1926. IIRC, the serial number of the first Orthophonic recording was 19623. Anything prior to that was purely acoustic.
Some of those early electrical recordings are fun to listen to. They just put a microphone out in front the the whole orchestra, which provided a concert hall echo effect.