Crosstalk-Cancelled Stereo: History and Potential
Twenty-five years ago two signal processing systems that claimed to be able to move sounds presented over stereo loudspeakers in three-dimensional space (including at height, and outside of the space between the speakers) were developed. Roland Sound Space (RSS) and QSound were briefly adopted for a number of significant commercial audio releases in the early 1990s: eg Sting’s The Soul Cages, Madonna’s Immaculate Collection, Bomb the Bass’ Unknown Territory, Woob’s 1194 and Roger Water’s Amused to Death. These systems followed on from Hugo Zucarelli’s Holophonics, a (quite possibly pseudo-scientific) system that was (nonetheless) employed on Pink Floyd’s The Final Cut and Michael Jackson’s Bad. There were also other systems, such as ‘Bedini Audio Spatial Enhancement’ (BASE) used on Cosmic Baby’s Stellar Supreme.
These technologies, and the productions that were created with them, are of significance for various reasons. They were controversial: Zucarelli was denounced in some circles as a fraud, BASE was criticised for sounding no different to crude stereo widening techniques that had been known about since the 1930s, some denounced the ‘phasey’ sound of QSound and RSS, and there was significant resistance from broadcasters who were concerned about mono compatibility, leading record labels to fear that music produced using this technology would not receive airplay. However, at least some of them were effective in terms of a greater range of spatial positions and apparently greater mix clarity due to the binaural release of masking phenomenon. It could be that a significant advance in spatial audio presentation and mixing clarity was spurned as a result of narrow broadcasting policy and misunderstanding by audio professionals.
This project examines the rise and fall of such technologies, by detailed analyses of relevant historic recordings and documents, and their place in present and future production technologies, by development and testing of new tools. A system that directly targets binaural release of masking for greater clarity in loudspeaker based presentation of audio is currently in development.