A U R O R A    P l u g - i n s

After measuring an Impulse Response, this module makes it possible to calculate the Acoustical Parameters defined in the ISO standard 3382, in 10 octave bands (from 31.5 Hz to 16 kHz). These include various kinds of Reverberation Time (EDT, T20, T30, Tuser), Clarity C50 and C80, Definition, Center Time.
The calculations are made accordingly to the ISO 3382 standard: the impulse response is octave-band filtered by means of IIR IEC-compliant filters, then it is squared (for obtaining the acoustic energy) and processed. For the reverberation time estimation, the squared impulse response is backward-integrated, with an optional noise-removal algorithm. Then a linear regression is performed over the proper dB range.
For example, from the following binaural (stereo) impulse response:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Pressing the  button these acoustical parameters are obtained:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

These data can easily be exported to other programs via the Windows Clipboard. After copying them to the clipboard, they appear in this way:

OCTAVE BAND ACOUSTICAL PARAMETERS Left Channel Band       Lin     31.5    63      125    250     500     1K      2K      4K      8K      16K Parameters C50 [dB]  -0.1349 -28.09  -29.91  -23.58  -10.6   -9.256  -5.846  0.6492  1.312   5.547   13.67 C80 [dB]  2.212   -21.17  -19.24  -13.48  -1.766  1.654   -0.6134 2.959   2.137   6.147   13.83 D50 [%]   49.22   0.1549  0.1021  0.4364  8.01    10.61   20.65   53.73   57.49   78.2    95.88 TS [ms]   89.58   303.6   176.    153.4   139.2   122.3   149.9   82.36   76.54   41.74   13.6 EDT [s]   1.602   5.882   2.38    1.831   1.759   2.618   2.378   1.499   1.489   1.274   0.8046 RT20 [s]  1.518   3.006   3.439   2.038   1.714   1.74    1.583   1.572   1.419   0.9592  2.203 r RT20    -0.9975 -0.7664 -0.9618 -0.9815 -0.9884 -0.9819 -0.9834 -0.9949 -0.984  -0.9922 -0.9435 RT30 [s]  1.507   --      --      1.828   1.674   1.644   1.498   1.483   1.379   1.334   2.618 r RT30    -0.998  --      --      -0.982  -0.9921 -0.9827 -0.9865 -0.9971 -0.9902 -0.9763 -0.966 RTU [s]   1.689   5.603   4.225   2.091   1.913   2.28    1.791   1.797   1.044   1.152   0.6691 r RTU     -0.9982 -0.9377 -0.9694 -0.8953 -0.9683 -0.959  -0.9847 -0.9975 -0.9935 -0.9719 -0.9237 Noise C.: yes     no      no      yes     yes     yes     yes     yes     yes     yes     yes RTU = RT User (-5. dB, -15. dB)