Characterisation of small room acoustics for audio production

Nowadays there is an explosion of home music production activities such as recording, mixing and mastering, which usually takes place in small spaces, which are not ideal for such tasks. Their reduced volume and the typical construction structure of homes, which usually have the common factor of strong walls facilitates the formation of standing waves and non diffuse sound decays which decrease the immersion sense and the realism of the program. The interference of the sound field with the relatively big size of the furniture and equipment in relation with the dimensions of the room affects also the quality of sound.
Coloration of sound perceived as a change of timbre, rhythm sensation and signal1 pitch is the main problem encountered in music reproduced in these spaces. It happens varying in a complicated way, as it depends on temporal and spatial variables. In order to minimize these problems, acoustic treatment needs to be applied to the room. The traditional ways of measuring rooms to assess this treatment had not taken in account the directionality of the sound energy and their effect in terms of perception of stereo image without blur estimation caused by harmful reflections, neither had taken in account what are the characteristics of neutral rooms.
This document aims to investigate the extraction and analysis of temporal and spatial distribution early sound decay. A method based on B-format signals is adapted to small rooms. It can map the spatial and temporal distribution of sound energy and diffuseness in three dimensions. Once the data is collected it is possible to extract the information in time and frequency domain and use it to infer issues of perception based on psychoacoustic models. The ultimate objective is to find out useful descriptors to characterize the acoustic quality in critical listening rooms.