Reverberation room

from Wikipedia, the free encyclopedia

A reverberation room is a specially designed room for acoustic purposes. It is constructed in such a way that the sound reflects to a very large extent on all walls and is evenly distributed in order to achieve a strong reverberation with a long reverberation time . Before the advent of electronic reverb devices, they were used in recording studios for sound processing. Today such rooms are used for laboratory tests and research purposes.

Hall of the TU Dresden

construction

The construction of a reverberation room determines its quality, which is expressed, among other things, in a long reverberation time and a uniform sound field .

The walls of the room are made of closed-cell, reverberant concrete , so that hardly any sound energy can be absorbed. To avoid flutter echoes and resonances , walls and ceilings are not built parallel. Panels are hung in the room, which serve as a diffuser and distribute the sound in all directions. Loudspeakers radiating from all sides and placed in a corner of the room are used as the signal source .

Since all objects brought into the room have a sound-absorbing effect, the measurement technology - with the exception of the sensors - is located with the test supervisors in an adjoining room.

function

Ideally, with the exception of the area directly around the sound source (see reverberation radius ) and directly in front of the walls, the same sound pressure prevails at every location . Such a sound field is called a diffuse field . Since the sound beams are incident from all directions simultaneously, there is no (directed) sound pressure in a reverberation room.
The room can be calibrated using reverberation time measurements or reference sound sources. The difference between the sound pressure level measured at any location in the room, far enough outside the reverberation radius and the sound power level of a sound source is determined. This difference is frequency-dependent and remains unchanged as long as the structure of the room and the degree of absorption of the walls do not change. In a reverberation room, the sound power of a source can therefore theoretically be determined with a single sound pressure measurement. This is e.g. B. very useful for questions in the area of sound insulation .

application

In the reverberation room according to DIN EN ISO 354 (2003-12) the degree of sound absorption of materials is determined. The sound absorption of noise barriers according to ZTV-Lsw 88 can be measured, the sound power of noise sources according to DIN EN ISO 3741 and the insertion insulation of sound capsules can be determined.

The following building materials and products are typically examined in the reverberation room:

  • Sound absorption: acoustic ceilings, wall cladding, furniture, theater chairs, curtains, light sails and in automobile interiors .
  • Sound power: fans, motors, drives, cellular base stations, gas meters, vehicle components.

literature

  • Stephan Demmerer: Simulation of sound fields on motor vehicles. Chair of Human-Machine Communication at the Technical University of Munich, 2002
  • Helmut V. Fuchs: Innovative room acoustics; Sound absorbers and silencers. Springer Verlag ISBN 978-3-540-35493-2
  • Helmut V. Fuchs: Transparent architecture and acoustics: The new Academy of the Arts Berlin. 2005
  • Dickreiter, Michael: Wolfgang Hoeg, Volker Dittel, Martin Wöhr, Handbuch der Tonstudiotechnik, 2008

Individual evidence

  1. ↑ Julia Winzer: Reverberation rooms, spring reverb, reverb plate, reverb foil. University of the Media, accessed in 2020 .
  2. ^ Research, acoustics and music technology, reverberation room. State Institute for Music Research - Berlin, accessed on July 13, 2020 .
  3. ↑ Do-it- yourself hifi - our reverberation room. Retrieved July 13, 2020 .