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Arbeitsgruppe 1.63

Round Robin in Room Acoustics

Please note:

PTB stopped its research activities in the field of room acoustics. Thus, the following information is provided without any further support.


In construction planning architects make to an ever increasing extent use of the computer to predict the acoustic qualities of a room, for instance of a concert hall. No software has however so far been in a position to replace a qualified and experienced acoustician. For developers and users of computer simulation software it is therefore of great interest to learn the differences of their results to those being measured on the same object.


That was the reason why the PTB as an independent and neutral institution started in 1994 the first international "round robin 1" with 16 participants from 7 countries. The object of examination was the auditorium of the PTB at its then condition and  the parameters T30, EDT, D50, C80 TS, G, LF and LFC had to be calculated in the 1 kHz octave band. The results showed such strong discrepancies between the different participants that a safe prediction of the room acoustical parameters for this room seemed to be impossible.


In 1996-98 the PTB organized another international "round robin 2" with 16 participants from 9 different countries and use of 13 different computer programs. This time the object under examination was a concert hall in Jönköping/Sweden named ELMIA-hall. The results of this round robin had been much better than those of Round Robin 1 but the complex design of this hall generated many troubles.


That's why in 1999 the PTB decided in agreement with most of the leading room acousticians in the TC of the EAA to start another "round robin 3" with a relatively simple structured room. This is the PTB studio which was intended to be examined in 3 phases. In phase 1 the studio had only plain walls, ceiling and floor with uniform absorption data, in phase 2 the real absorption coefficients were added without changing the simple geometry and in phase 3 all design details and geometrical data had to be regarded. This round robin is finished.


PTB stopped its research in the field of room acoustics. That’s why the results of the 3rd round robin are given without any further support. Please refer to prior publications for more details: For the 1st round robin see [1], for the 2nd round robin see [2, 5] and for the 3rd and last round robin see [3, 4].


Files provided:



[1] Lundeby, A., Vigran,T.E,, Bietz, H., Vorländer, M.: Uncertainties of Measurements in Room Acoustics, Acustica Vol. 81 (1995), S.344-355

[2] Bork, I.: A Comparison of Room Simulation Software -  The 2nd Round Robin on Room Acoustical Computer Simulation. Acustica united with acta acustica Vol. 86 (2000), S.943-956

[3] Bork, I.: Report on the 3rd Round Robin on Room Acoustical Computer Simulation – Part I: Measurements. Acustica united with acta acustica Vol. 86 (2005), S.740-752

[4] Bork, I.: Report on the 3rd Round Robin on Room Acoustical Computer Simulation – Part II: Calculations. Acustica united with acta acustica Vol. 86 (2005), S.753-763

[5] Proceedings of the Institute of Acoustics Vol24, Part 4, 2002, published in July 2002, presented at the Auditorium Acoustics Conference, London