AIST-Laboratory

A considerably up-grated (January, 2006) AIST 3.3 version of our new-generation simple in usage AIST Room-Acoustics software has been released. It is founded upon the ray tracing technique, with:

1) Arbitrary room geometry bounded by a finite number of planes (up to 1600 planes, up to 30 edges for each);
2) Convenient interface, with 3-d view of the room model;
3) The up-dated 3.3 version operates with a standard corners-planes way of geometry assignment;
4) Double-sided planes are allowable;
5) Both absorption and diffusion coefficients, specific for each plane. All coefficients are described from the user's (excel) "Materials database" file that permits common calculations for all octave bands;
6) Acoustic impulse and respective Schroeder decay curve;
7) Diagram showing ray paths of reflections of arbitrary order, with different colors for specular and diffuse reflections;
8) Calculation of eight main acoustic parameters in the six 125-4000 octave bands, in accordance with ISO 3382;
9) Full compatibility with AUTOCAD in geometry assignment;
10) The program can calculate RASTI and STI;
11) It keeps in a table the full array of dots on the receiving impulse curve.

Our principal strategy is to develop the most rapid code, which permits the program to be run within a few minutes (typically 2-5 minutes on a 800 MHz processor). This guarantees 5-7% precision of computations for chosen set of physical and geometrical parameters.

Recently this program participated in all three phases of the Round Robin III competition, organized by the Aachen University (Germany), among other 10 leading world-wide programs in Room Acoustics, and has shown good results compared with experiments and with other famous programs.

You can download a FREE Software with absolutely analogous possibilities, which is restricted in geometry of the room only. You may assign and observe arbitrary geometry there but calculate any room with up to 15 reflecting planes only and of not too elongated proportion. DOWNLOAD (530 Kb)

In particular, by this working program you can run with 7-planes geometry of the Phase I, Round Robin III, Aachen University, Germany (see site http://www.ptb.de/en/org/1/_index.htm) on acoustics of their Recording Studio. This will allow you to compare with other (confidential) participants, representing all nowadays world-wide famous programs (the file "results_p1_fp.xls" can be found on the above PTB site, but it is also attached to the DOWNLOAD button above). The list of those world-wide Room Acoustics Softwares, existing at present, can be found on the site: http://www.arch.ethz.ch/eggenschwiler/links.html.

You can also download a demo Software, which runs with a certain very elongated sports-hall of a fixed geometry and very disproportional absorption. DOWNLOAD (400 Kb)

System Requirements:
Windows 95, 98, 2000, NT. Memory - 32 Mb. Processor - Pentium/100 and higher.

If you decide to purchase our full AIST Room Acoustics Software, choose appropriate version among others of the cost between 380 and 670 Euro, with a Licence permitting installation by any user from the staff of your Company / Laboratory. We can deliver the Software by e-mail.

To order, contact us to the following e-mail: sumbat@math.rsu.ru

Aist-Lab, sumbat@math.rsu.ru

A new up-dated (January, 2006) AIST 3.3 version of the room-acoustics Software with some principal improvements is now available, which provides:

1. An improved interface: For more convenience, a 3d view of the room model has been added. It can be used with the mouse and keyboard to navigate for a comfort field of the view (rotation: by the mouse, shift along the axes: Ctrl with mouse motion, and zoom by + and -). In all views (projections or 3d view) it was inserted the capability to save the panel of view in a bmp-file. In the projections view the mouse cursor coordinates are displayed in the status bar. Planes, sources and receivers edit dialogs were improved and have a design clear for users. The Program may be used for various positions of sources and receivers, calculations and comparisons of results. If you open the “Planes” panel and click to any plane, you can observe selected plane both in three Cartesian projections and in the 3d image.

2. Now the 3d model of the room can be saved in text, Excel or AUTOCAD-dxf files and can be opened as text, Excel or AUTOCAD-dxf (with the only restriction to not use 2-d tools) files. For models saved in text or Excel files the program saves the used materials with absorption and diffusion coefficients, the sources and receivers, the results of calculations as well as the path to the file where calculated impulse data was saved. For models saved in dxf-files there is saved only the set of planes.

3. Materials database, which can be saved in text or Excel files, is realized as a list of material names, six absorption and six diffusion coefficients. This permits common calculations for all octave bands. The user can attach different materials database files to different models.

4. If you don’t need a high-precision calculation then you may choose the time of calculation in percents from that is assigned by the program automatically as a regime of extremely perfect precision.

5. Precision of this version is considerably improved, due to some modifications in the Ray Tracing algorithm. The number of rays now is taken automatically, to provide desired precision (near 5 %). In extreme cases this can achieve 500.000. Besides, the number of re-reflections (which is chosen also automatically) can achieve so high value as 700, that is necessary for rooms with planes of very low absorption.

6. Now there is an opportunity to assign double-sided planes, that is important when their thickness (like a curtain, or a glass shelf, or a table surface, or a special reflector above the stage) is small compared with the wave-length. A sample Sample1.acr file is attached as an example for your use.

7. This program shows (in a “Views” field) a shape of acoustic impulse and respective Schroeder decay curve, and corresponding numerical data for the both of them can be saved in a separate (excel or text) file. Of course, you can save also the images drawn, by using a standard WINDOWS “Print screen” command, as a *.bmp-file.

8. Two new demos are available, which you can use as a full version, with some restrictions in geometry only.

Aist-Lab, sumbat@math.rsu.ru

AIST-Lab (Advanced Information and Scientific Technologies Laboratory) was created in 2000 by its head and leading specialist, M.A.Sumbatyan.

M.A.Sumbatyan is Full Professor of Applied Mathematics and Acoustics, Rostov State University, Russia (conventionally recognized as the one of a highest education and research quality, among other five best Russian Universities). He is a Member of the Russian Acoustical Society, and Full Member of the Acoustical Society of America.

As a Visiting Professor, M.A.Sumbatyan visited for a scientific cooperation the Universities of Bologna, Salerno, and Catania (Italy), the Strathclyde University (Glasgow, Great Britain), Chalmers University of Technology (Goteborg, Sweden). He also participated in a Program of scientific cooperation between Rostov State University (Russia) and the University of Dortmund (Germany).

Selected Publications in the field of Room Acoustics:

1. On calculation of sound rays reflected from non-plane surfaces in room acoustics. - XIII Session of the Russian Acoustical Society, Moscow, August 25-29, 2003 (with N.V.Boyev) See .
2. Short-Wave diffraction on bodies with an arbitrary smooth surface. - Doklady Physics, 2003, Vol 48, 540-544 (with N.V.Boyev).
3. Some explicit results for three-dimensional Helmohltz operator in polyhedra. - Reports Math. Physics, 2001, v.47, N 3, p.371-379 (with A.Pompei).
4. New explicit solutions in acoustics of closed spaces on the basis of divergent series. - J. Acoust. Soc. America, 2000, v.107, N 2, p.709-713 (with A.Pompei and A.Rigano).
5. High-frequency diffraction by non-convex obstacles. - J. Acoust. Soc. America, 1994, v.95, N 5, p.2346-2353 (with N.V.Boyev).
6. Short-wave diffraction by arbitrary smooth obstacles in two dimensions. - Russian Phys. Acoust., 1992, v.38, No.3 (with I.D.Druzhinina).

Aist-Lab, sumbat@math.rsu.ru