STI-Matrix - Calculation & Evaluation

Calculate STI-Matrix

The STI matrix is used to determine speech intelligibility between all pairings of speaker-listener positions in a room.

This procedure has proven to be preferable compared with the former determination of the speech level and of the STI along specified paths when evaluating the expected room acoustical quality in the planning situation.

Example

Path: Files\Manual\Chap 9_3

The procedure required for generation of the necessary data structure is explained in detail in the referenced document.

After having completed the preparation of the data structure of the CadnaR model, the calculation of the STI matrix is launched using this command on the Extras menu.

The calculation may take some time, depending on the size of the model, the number of workplaces, and the computing performance available. The result files generated by CadnaR must not be edited, renamed, moved or deleted.

Evaluate STI-Matrix

This command in the Extras menu starts the evaluation of the STI matrix calculation results.

Prior to the evaluation, select whether A-weighted noise levels from 25 dB(A) to 55 dB(A) in steps of 1 dB steps shall be used or the entered noise level spectrum (see "RIR-Evaluation" tab). With option „noise spectra from 25 dBA to 55 dBA“, the presently selected noise level spectrum is normalized to a sum level of 0 dB for generating the octave levels.

The further procedure when evaluating the STI matrix is explained in the above-mentioned document.