DIRAC Room Acoustics Software Type 7841 Evaluation Copy

Version 5

DIRAC PC software is used for measuring a wide range of room acoustical parameters. Based on the measurement and analysis of impulse responses, DIRAC supports a variety of measurement configurations. For accurate measurements according to the ISO 3382 standard, you can use the internally generated MLS or sweep signals through a loudspeaker sound source.

Survey measurements are easily carried out using a small impulsive sound source, such as a blank pistol or even a balloon. Speech measurements can be carried out in compliance with the IEC 60268-16 standard, for male and female voices, through an artificial mouth-directional loudspeaker sound source or through direct injection into a sound system, taking into account the impact of background noise. DIRAC is not only a valuable tool for field and laboratory acoustics engineers, but also for researchers and educational institutions.

New in version 5

Windows 7 compatible
Horizontal and vertical zoom using the mouse wheel
Horizontal and vertical panning using the mouse
Cursor lock to graph for easy readout of signal values
More spectrum smoothing options up to 1/24th octave
All measurement options and info moved to measurement dialog
Project tree in parameter graph window with flexible graphing options
Reference curve in parameter graph
Much faster calculations when exporting multiple parameters for a project

News in version 4.1

Added the Sound Insulation Index (SI) parameter described in the ENV 1793-5 standard.

Added the option to save WAVE (.wav) files without Dirac specific information. This makes it possible to use WAVE files created by Dirac with software that does not support RIFF INFO chunks, such as MatLab.
The Save Project Data function now saves parameter values for both channels where possible.
The Leq, LAeq and LCeq are now only available when the external impulse measurement method is used, or when the measurement stimulus has a white spectrum (e.g. MLS and lin-sweep, without source filter). For nonwhite stimuli, the Leq is not valid due to the particular implementation in Dirac.
The BR(L) is now only available when a system calibration has been applied to the measurement. The system calibration compensates for the influence of the measurement chain on this system parameter.
Asynchronous measurements now result in higher INR values.
The criterion for displaying (and colouring) speech intelligibility values has been changed. These values will be displayed in grey when, in one of the relevant frequency bands, the INR is lower than 15 dB or the MTF cannot be calculated.
The default name for saved tables and graphs now includes the project name.
Fixed a software problem, making the free field system calibration available again.
Fixed software failures that could occur while canceling auralisation calculations and while mixing noise.
Sound devices are no longer erroneously marked asynchronous during the sound device calibration procedure.
Decimal points and comma's are no longer mixed in saved tables. Improved IR length calculations.
Improved scale model air absorption compensation.
Updated HASP libraries to support Win64.
Replaced Process-Subtraction by Reflection (Qw and RI) and Transmission (SI).
Allow independent time window setup for both channels.
Added function to swap 2 channels.
Added group select dropdown list in file select window.
Added support for B&K .wav files.
Added Drag & Drop support to main window.

Upgrade
To upgrade to version 4.1 from version 4.0 or earlier of DIRAC Type 7841, please contact your local sales representative.

New in version 4.0

Much improved asynchronous measurement results
Asynchronous measurements can now have almost the same quality as synchronous measurements, and can be averaged to increase the INR. Measurements where a CD or MP3 player can be used to remotely play back an MLS or sweep stimulus are important when measuring the speech intelligibility of PA systems in train stations, stadiums, airport halls, etc.
Option for manual entry of SNR values for STI calculations
Using asynchronous measurements with pre-averaging, you can now measure the noise-free speech intelligibility. Later you can easily investigate the impact of noise by manually entering different SNR values
New parameters
C30, CX, DX, IACCX, RT, TX, Hallmass (H), Bass Ratio (BR(RT) and BR(L)), LAeq, LCeq, Magnitude Pink (3dB/octave compensated magnitude view). You can specify your own integration intervals for Clarity (CX), Definition (DX) and Inter-Aural Cross Correlation (IACCX). You can also define a custom decay range for the reverberation time (TX). All custom-defined parameters are available in table and graph formats and can be saved, copied, printed, etc.
User defined parameter tables
In addition to the pre-defined tables for reverberation, energy ratios, spaciousness etc., you can now define your own tables to contain exactly the parameters you need for the job at hand
Project save and load functions
When working with a large number of measurements, this can be a big time-saver. The group setup in the statistics window, and the files contained in these groups can now be saved in a project file. The project file can later be opened again for quick access to all files in the measurement session
Calculate and export multiple parameters in a single operation
You can now specify any number of parameters that should be calculated for a particular project. The results for all these parameters for all impulse responses in the project are written to a file that can be opened in a spreadsheet program
Forward integration view
Undo function for waveform Edit operations
The number of operations that can be undone is only limited by the size of your disk drive, so for all practical purposes the Undo is unlimited
Auralisation function
The auralisation function will automatically resample the IR to match the sound material. You can correct the results for the frequency response of the sound source that was used to capture the IR to remove the colouring caused by the source
Overlays in time and frequency domain views
You can now compare measurements graphically to the level of individual reflections. The impulse responses can be aligned perfectly based on a crosscorrelation, and you can quickly switch the foreground and background curves
Optional linear scale in ETC view
By popular request the linear scale for the Energy-Time Curve, or reflectogram, is back
Optional grid in time and frequency domain views
You can now also change the graph colours
Faster sound device calibration procedure supporting a wider range of devices
DIRAC no longer requires that the sound device (driver) support the mixer API. Only the wave API is required. This enables the use of many sound devices that use their own proprietary mixer software
Support for 24- and 32-bit sound devices and .wav files
The maximum sample rate is increased to 192 kHz for high quality 1:10 or 1:20 scale model measurements
Resampling
Option to change the sample size and sample rate of a measurement using a high quality resampler
Sound source protection
Optional bandlimited sweeps to protect the sound source
AutoMeasure
AutoMeasure can now also be based on a time interval instead of a trigger signal. This is useful for monitoring applications where a measurement must be taken regularly regardless of the presence of any sound

Evaluation Copy

If you do not own a valid license for DIRAC you can download the file below and run DIRAC in Demo mode. The Demo version will not allow you to save files, and only calculates parameters for the 2 kHz octave band.

Note: This evaluation copy is NOT a full version of DIRAC Type 7841, but a subset of the full programme to minimise the size of the downloadable file.
Even with a valid license it will only run with limited functionality.

Version 5

Filnavn	Filtype	Størrelse	Sprog	Frigivelsesdato
DIRAC 5	ZIP	9.1 Mb		marts 1. 2011