Auralisation

What sound pressure level is assumed in the database, i.e. at which distance from the source and for which reverberation time?

Answer
In both cases, the sound pressure levels are linear (not A-weighted) diffuse field levels. At the outside, it is the level 2 meters in front of the facade, i.e. including the own facade reflection.

What is auralisation?

Answer
In the context of BASTIAN, auralisation means to make the sound insulation between rooms or between the outside and the inside audible. This could also be referred to as an Audio Demonstration, since the sound is not reproduced in an exact sense. By selecting a sound source and the type of receiving room (size & reverberation time), the received sound signal is generated taking the calculated sound insulation into account. The auralisation software calculates the binaural head related transfers functions for 5 directions of incidence. The reverberation of the receiving room is represented by its impulse response. See paper.

When trying to start the auralisation I can’t hear anything?

Answer
If all settings in your system volume control have been set properly (see Auralisation Help), a problem can result 1) from the fact that BASTIAN assumes the BASTIAN-CD-ROM being in your CD-ROM-drive when starting to play or create a sound file. If the BASTIAN-CD-ROM is not in your drive you will be prompted to locate the BASTSNDS-folder. In case you have decided the copy all sound files to your hard disk please select the folder via the file selector box. 2) another reason may be that the calculated sound insulation is high and you try to listen to a faint sound on the recieving side. The background level has to be low enough. You may choose an uncalibrated (amplified) output for demonstration purposes. With v 1.1: simply copy the final sound insulation values obtained by calculations reduced by 20 or even 30 dB to a fictive construction. Add this construction to the list of elements, recalculate and repeat the auralisation procedure. With v 2.0, choose 10, 20 or 30 dB amplification by the radio buttons (with care). Amplification should be adjusted such that levels are close to background levels of the listening ambience where your demonstration takes place.

I would like to present some auralised sound files during a presentation in a seminar room. What will I need for this as amplification?

Answer
(See also the previous item.) We in general recommend external powered speakers for the auralisation tool to produce a sufficient volume for a realistic impression, flat response within 50-10000 Hz. We recommend the use of Genelec 1029 powered speakers or high-end headphones.

Do I have to order the auralisation directly with the calculation program?

Answer
Definitely, we would like that you order the auralisation software with the calculation program. However, you can also order the calculation program first and the auralisation software later. The auralisation is an optional extension which needs the calculation program, but not vice versa. Once you have started to use it, you don't want to go on without. Acoustics is about listening, after all.