If the recording was made before the early 1950s, it doesn't employ RCA Victor's "New Orthophonic" technique. The sound was definitely improved, it is especially noticeable in orchestral recordings. The overall clarity of the sound is quite apparent. At least part of the improvement in sound was due to the simple fact that RCA began recording using magnetic tape in late 1949. Many RCA Victor releases state they are recordings are "New Orthophonic" on the jackets even if they aren't. It was largely just a marketing slogan as I said. For example, two early Elvis Presley releases For LP Fans Only and A Date with Elvis contain dubbings of Elvis's Sun 78s with echo added. They obviously were not recorded using the "New Orthophonic" process. RCA Victor was the US distributor for EMI in those days; EMI recordings were issued in the US as "New Orthophonic" as well.