1933 - Chopin - Impromptu No. 1 in A flat major, Op. 29

Commercial recording - These recordings are professionally made studio recordings. Up until the 1950's, they were recorded as 78-rpm record sides, fitting up to ca. 5 minutes of music each. Each side had to be recorded in one continuous take and no editing was possible. Sometimes this necessitated multiple takes to achieve a satisfactory result - though many of Cortot's recordings were successfully made in 1-2 takes per side.