It’s a treat to be able to see these giants of the past (and of the present) in action. The Bach Concerto receives, by modern standards, a stolid performance, with slow speeds and heavy, unvaried accentuation. But there’s still some beautiful interplay between the soloists, particularly in the second movement, and it’s most instructive to see how freely these two great violinists use their bows.

There is an excess of the furrowed brow in the Mozart, too – here it’s not so much a matter of tempo as of failing to point up the moments of witty repartee, and of an expressive style that’s more earnest than graceful. It’s a delight, nonetheless, to witness the Oistrakhs’ magnificent uniformity of bowing, and to see and hear David as a great viola player.

The visual presentation of these two performances is fairly basic, concentrating for the most part on one or other of the soloists (or both of them) with occasional long shots of orchestra and conductor. Brian Large’s film of the Brahms is more imaginative: as we take in different views of the soloists and different perspectives of the orchestra we become an absorbed listener (not one with Attention Deficit Disorder, as with some more recent TV presentations), following all aspects of the music. It’s a magnificent performance, too, strongly directed by Kondrashin. The soloists form a fascinating contrast: David Oistrakh undemonstrative, a powerful presence out of whom the music flows, Rostropovich living each musical moment in gesture as well as sound, and playing to his partner in the most inspiring way.