Perception of low frequencies in small rooms

Critical listening rooms are spaces carefully designed to provide the listener with an accurate listening environment. It is well known that in small rooms, resonances may occur that will cause some amplification or attenuation of sound at certain frequencies. These problems are known to cause a distraction from the optimum perception and the correct judgement of the reproduced sound.

A study has been carried out on various factors that affect how “bass” is perceived in rooms. Parameters like the modal distribution and the Q-factor of modes have been studied using a binaural technique that employs virtual representation of different sound fields. This technique allows different room conditions to be compared relatively quickly without actually having to change the conditions in a real room. The purpose of this study is to identify the subjective perception of these factors and to attempt to classify its perceptual importance with regards to time and frequency domain effects introduced by resonances.

Results indicate how changes to these factors are subjectively perceived by users. In practice these results may be applied to a more efficient use of acoustical treatment and aid the design of better rooms.