top of page

Amateur Kit Creatorsグループ

Leigh Sylvester
Leigh Sylvester

Catt Acoustic V9 Rapidshare

Note 1: if you have an old demo version installed uninstall it first and then also delete the old Xtra32.DAT license-file from the old installation folder, the uninstall process will not do it since the file was added after the installation. Note 2: in a few cases it has happened that the separate data-installer did not start when CATT-Acoustic was run for the first time. Calculations will then fail since no Surface properties library can be found, or if not used a Predict SxR TUCT will fail. If so, close CATT-Acoustic and run the installed cattdemo_data.exe and after restarting CATT-Acoustic select File Preferences and confirm the "CATTDATA " folder and then select your Prefs.

catt acoustic v9 rapidshare

CATT-Acoustic is a room acoustic prediction program that includes many prediction methods and tools. Each methods has its special benefits and drawbacks and can be selected depending on case. Many times it is beneficial to view the results of different types of predictions side by side.

CATT-Acoustic is a software program that offers various methods and tools for predicting room acoustics. It allows users to compare the results of different prediction methods and select the one that best suits their needs.

These sources and their orientations are exported in CATT-Acoustic software, with generic directivity filenames though (catt.SD1). Groups can be differentiated thanks to comments and different generic emission levels, to be tuned inside CATT-A.

3. Mini-tutorialBelow are shown typical steps predicting theacoustics of a simple shoebox-shaped hall with one source and onereceiver to give you a feeling of what it is all about. Thisexample is a "mini-tutorial" and is kept as clean as possibleavoiding most of the more advanced features that are used in theExample hall in the help-file Section 2.3 and in the dedicatedTutorial in Section 11. In addition to direct use of the flexiblescripting language in the GEO-format, models can be created via anAutoCAD AutoLISP interface (not included in demo version, seehelp-file section 10), via DXF import (see File External CATTTool DXF2GEO) or via 3rd party SketchUp tools ( for available plugins). The procedure hereuses only the GEO-format since even with a CAD export basicknowledge of the GEO options is essential. Start CATT-Acoustic v8.The Prediction module window opens up directly, note that TUCT onlyis checked so that only controls used with TUCT are enabledinitially. The Plot-file viewer module is also open and fills alarge portion of the frame window CATT-Acoustic v8 and TUCT areMultiple Document Interface (MDI) applications so that the menu-baritems may change when a different module is activated. A list ofavailable and open modules can be found on the Window menu and inCATT-A v8 all open modules are shown as toolbar icons (to the rightof the standard New, Open and Save icons).

semicolon ";" and blank lines are allowed. See help-file section2.3 for full details and in this manuals Appendix for a shortsyntax description.;MASTER.GEO ;constant declarations LOCAL h = 8;hall height in m LOCAL w = 10 ;hall width GLOBAL d = 24 ;halldepth ;absorption and scattering coefficients 125Hz to 4kHz [%],optional RGB-color ABS audience = L 255 0 0 ABS wood = L 255255 0 ;Notes: ;- if 8k and 16k values are known they can be givenafter ; a colon as in otherwise they ; are extrapolated from 2k and4k values. ;- RGB-color is optional, one will be auto generated ifnot given. ;- scattering coefficients are optional (but stronglyrecommended) ; if not given the default values in General settingswill be used CORNERS ;floor corners 1 -w/2 0 2 -w/2 d 3 w/2 d 4 w/20 ;ceiling corners 11 -w/2 0 12 -w/2 d 13 w/2 d 14 w/2 0

Note that global constants defined in a GEO-file, in this cased, can be used in sourceand receiver-files. 100 receivers can beused numbered from 0 to 99. Save REC.LOC. Select (Edit) Source-fileand SRC.LOC and enter the source data, each source occupies anumber of lines. Source data items are source ids, source positions(x, y, z), source directivities, source aim points (x, y, z) or asa function aim(H,V) specifying horizontal and vertical aimingangles, SPL values for the six octave-bands at 1 m distance fromthe acoustic center on the axis. Optionally source roll angles, 8kand 16k 1 m SPL values can be given, see Help. This simple exampleuses the pre-defined natural omni-directional source OMNI and if anelectro-acoustic source, such as a loudspeaker is used, the sourcesyntax is slightly more complex adding a Lp1m_ea or Gain_a line anda Delay_e line, see help-file section 2.3 (CATT-Edit has a Templatemen to insert common constructs).;SRC.LOC LOCAL src_z = 1.7SOURCEDEFS ;id --pos x y z-- directivity -- aim point (has noeffect with omni) -A0 1.0 1.7 src_z OMNI 1.0 3.7 src_z Lp1m_a = ;SPL at 1m on the source axis 125 Hz to 4 kHz

260 sources can be used numbered A0, A1, A2, , B0, B1, Z8, Z9.Source directivities are handled in the Directivity module, seehelp-file Section 4. Note how a local constant, src_z, is used toensure that the source is aimed in the horizontal plane (takes noeffect in this case since the source is omni-directional). SaveSRC.LOC. The Create a New Project utility also created a basicprediction settings-file GEO.PRD automatically loaded when theproject was created. Select General settings and browse through thevarious items. In the geometry file specific scatteringcoefficients were given but for surfaces with no given coefficientsthe Surface default will be used. Diffuse reflection can affect theresults very significantly, see help-file Calculationrecommendations (section 2.5).

CORNERS c_id c_x c_y c_z ... (more corners, can also use loops,see below) PLANES [ pl_id pl_name / c ... / abs ] or a sub-dividedplane [ pl_id pl_name / c ... / ( sub_name / c ... / abs ) ... ]... (more planes, can also use loops, see help-file) MARKERS ...(optional section for non-acoustical visual elements, seehelp-file)

In order to correctly design a sound system, sophisticated modeling softwares based on Geometrical Acoustics are needed, and constantly fed by the data of the acoustic measurements in the field. Certainly a 2D plan is of very little use when representing the complexity of reality.

We remember that we are dealing with a room and not with a rectangle. and rooms are not just 3D anechoic perimeters. They have walls and surfaces, with their specific acoustic properties (even in the most complex software, only characterized with approximation).

Now consider that between these two extreme cases, which we find in the anechoic chambers and in the reverberating chambers, in reality we have an enormous amount of possible variations which we can find in our rooms, according to the different types of acoustic characteristics of the surfaces and walls.

Geometry and mathematics, as well as the acoustic modeling software which is based on geometry and mathematics, are certainly important. But in my opinion it is necessary to return to giving a different meaning to these tools, bringing them back to their natural riverbed of belonging, namely that of tools for verifying and extending human intuition and experience.

From the RIR, opportunely gathered and processed, we can immediately obtain all the acoustic parameters that describe our room and that can be integrated into acoustic modeling software, to make sure that the predicted data is as close as possible to the real data.

The highest point of the acoustic modeling is the synthesis of the impulse response of our model. It can therefore be compared with the measured one. Both can be listened to through convolution processes, adapting the design choices accordingly. In all these steps, the ear and the person are always at the center, protagonists.

It is therefore necessary to measure the room and use the calculated acoustic parameters to integrate the acoustic modeling software. The geometry that becomes Acoustic. It is the only practical way to project spherical speaker data on a flat surface.




bottom of page