Resumen
Resonant vessels in ancient and medieval buildings are the subject of some historical and acoustic research today. There have been a number of detailed surveys of European churches, where acoustic pots remain in the buildings. Despite the fact that in medieval Russia the use of built-in vessels was very common in the construction of churches, they have been hardly considered in recent publications. Therefore, the first goal of this paper is to give a brief overview of the Russian experience. Some of the most interesting examples of Russian churches are presented, and among them there may be a world record for the number of the vessels in a single room. The Church of St. Nicholas in Pskov has about 300 pots inserted into the walls, apse and pendentives. The second goal is to study the efficiency of acoustic vessels in an ordinary room. Acoustic measurements were carried out in the Rachmaninov Hall, which is part of the Moscow Conservatory. This chamber concert hall built over 100 years ago has 29 vessels. The first conclusion is that the vessels behave like resonators, their natural frequencies have been identified. The second conclusion is that we found no considerable changes of the acoustics due to the vessels.