Historical classical music recordings are generally classical music recordings made prior to the stereo era of vinyl disc recording, which began around 1957.[1][2]
As time passes, even later recordings, made in the early stereo era are also being released as "historical" recordings, especially if they were never released or were dropped from the record catalogs due to loss of popularity or "antiquated" sound. Typically such recordings are of artists and performances that were particularly notable at the time they were first released, or were unavailable because they were private recordings made at concerts or radio broadcasts. The latter can be of rather high quality if the recording derives from tapes made and archived by the broadcaster or the organization mounting the performance.