This parallel recording comtpares the very dry, precise studio sound (here in the acoustics of the Teldex studio, strings at studio orchestra strength and the sound of a New York Steinway from the 1950s), as can be heard in recordings with the composer in the 1940th, with a sound that one might expect in a modern concert hall (here the acoustics of the Berlin PhilharmonyHi, with larger orchestral line-up and a current German Steinway D).
In the first movement, the score contains two different cadenzas by the composer. The older one is a little longer, has more sonority and is still chosen by Russian pianists today. The younger one is a little shorter and faster and was mostly played by Rachmaninov and the pianists today because it fits better into the overall movement.