Reproducing Commercial Multichannel Formats Through a Single Monitoring System

A modern audio production facility must be able to supply productions in a large number of different formats. The change from mono & stereo to multi-channel reproduction has created many problems, both in converting existing production facilities to multichannel format and when building new installations. This paper examines the LFE channel across different encoding formats and presents a method to reproduce it, using a bass management system, through a single monitoring system. Introduction Today, a modern audio production facility must be able to serve productions in a large number of different formats. The change from mono and stereo to multi channel reproduction has produced many problems, both in converting existing production facilities to multichannel format and in new installations. The audio formats that must be handled by a modern production facility currently include mono, stereo, matrix four channel formats, five 5.0 systems, 5 channel systems with a separate Low Frequency Enhancement channel (5.1 systems) and advanced multichannel formats such as 6.1 and 7.1. This paper presents a brief overview of the current multichannel formats and a hardware solution to reproduce all these formats using a single loudspeaker system. Loudspeaker set-up for multichannel audio The ITU that issues many recommendations for various application areas, and offers two recommendations that are of particular interest for surround sound reproduction: ITU–R BS.775–1 [1] and ITU–R BS 1116–1 [2]. The following sections highlight the most important points of these recommendations with regard to the LFE channel and subwoofer. Placement of the subwoofer in the room Psychoacoustics research work has shown over the years that the very lowest frequencies have minimal audible stereophonic effect and hence may be reproduced by a single source [3, 4]. However, in some relatively recent, but uncorroborated, research [5], it is suggested that for best psychoacoustic perception results