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Recreating room measurements

📄️ PTB Studio

The Physikalisch-Technische Bundesanstalt (PTB institute) organized a series of room acoustic simulation round robin tests to test the capabilities of various software implementations. The first international round robin was conducted in 1994, followed by the second in 1996-1998. 16 participants from 9 countries, using 13 different programs, participated in Round Robin 2, which examined a concert hall in Jönköping/Sweden named Elmia Hall. While the results of Round Robin 2 were an improvement compared to those of Round Robin 1, the complex design of Elmia hall caused difficulties in interpreting the results. Consequently, in 1999, the PTB decided in agreement with leading room acousticians in the technical committee of the European Acoustical Association to start Round Robin 3, on a relatively simple structured room, to have a good control over the scene and boundary materials. In Round Robin 3, over 20 simulation tools were used to simulate the studio room of PTB institute [1]. The room was measured and the material properties of all surfaces in the room were obtained in octave bands 125 Hz - 4k Hz. The PTB Studio itself is relatively small, with special diffusors (volume of 400 $m^2$ ). A strong standing wave was present in the room and a large part of the wall area could be covered with curtains. Results were given both with open curtains and closed curtains.

📄️ Complex lab facility (Part 1): Full bandwidth wavebased simulation

The study measured the capabilities of Treble’s wave-based solver in a medium-sized room of 80 cubic meters. The solver was tested for full-bandwidth up to 8kHz and both mono and binaural room impulse responses (RIR) were measured using a directive source and a KEMAR mannequin at various positions. The simulations were carried out on a cluster with six Nvidia A100 GPU cards running in parallel. Results are compared and presented for Energy Decay Curves and derived acoustical parameters, reverberation time T20 and early decay time, for the mono RIR. The binaural RIR results are compared both in the frequency domain and in the time domain.