Most of the acoustical measurements in theatres, concert halls and musical spaces are performed by using a single omnidirectional  pressure microphone.
Useful for reverberation time and other monophonic parameters
NO information about the direction of arrival of the sound
Introduction
Most of the acoustical measurements are performed by using a single omnidirectional pressure microphone. An omni microphone is good for deriving from the Impulse Response, the reverberation time and others monophonic parameters. But what about the direction of provenience of the sound? What is causing a bad reflection? So let’s have a look to the impulse Response: we have to individuate the reflection, we have to calculate the distance between it and the direct sound in terms of meters and then we have to imagine the source of this reflection inside the room under test. Ok, it works, but in some cases it’s a matter of “intuition”