r(m) – Direct sound distance

When computing room acoustics parameters as default the the direct sound distance r(m) is computed. Shown below is how this is displayed when the parameters are calculated from the Calculate menu.

If the Time Data plot type is displayed, the time window lower limit is also updated as shown in the figure below.

To compute the distance in meters, the speed of sound is needed. The formula for computing the speed of sound is given below:

Speed of sound = 343.3 + 0.6*(temperature – 20);

The temperature used in the formula below is specified in Calculate->Strength->Strength Settings…. In this dialog, select the setting shown below

Then click the  button to open the dialog shown below where the temperature can be specified.