O Fortuna....
by the Red Army Choir.

Hence this picture (which is nice in its own right).

A Red Square parade, 1941, by Konstantin Yuon
Alternatively, you can listen to a different (but still Russian) rendition of Orff's music at:
Interesting video. It's a shame those T-80's wouldn't have lasted more than 72 hours on the Inner German Plain. :) But they do jump over things very nicely. Too light! :P
The artillery looks very good....