This definitive stamp (Scott 6560) features the organ at the Moscow Conservatory in Russia. This stamp was issued in 1999 (the imprint shows 1998), following currency re-valuation. A similar stamp was issued two years before, with high-denominations, before the currency change. The organ and Piotr was built by the Cavaille-Coll firm of France. A relationship between organist-composer Charles-Marie Widor and Piotr Illyich Tchaikovsky led to the decision to work with Cavaille-Coll. Apparently Widor felt a French builder could best capture the pathos of Russian musical sensitivities in the new organ. The new instrument was built in 1896, but went first to the Paris Exhibition before being installed in the conservatory, an interestingly circuitous route. After work on the instrument three times in the imd- to late 1900's, by the 1990's heating and cooling issued in the hall had damaged the organ such that it was unplayable.
Note: there are 3 versions of this stamp:
1997, 5000 rubles, Scott 6382
1998, 5 rubles, Scott 6433
1999, 5 rubles, redrawn, with micro-printing replacing the vertical lines in the background, Scott 6560
I have the 1998 pictured here, and it's the only version I own.