Number representing the silence threshold referred to the volume level. Supported values are expressed with a linear volume in the range from 0 to 32767. If for example you should set a value of 800, any portion of sound having a volume level lower than 800 would be considered as silent.
In case you should need to set a threshold value expressed in dB, before setting this parameter you could convert the value in dB into a linear value through the following formula (C syntax):
ValueLinear = 32767 * pow (10, ValueInDB/20);
In case you should need to define different thresholds for the initial and final portions of the recorded sound, use the TrimSilenceEnhanced method.