An Evaluation of Spectral Redistribution as an Upmixing Algorithm for 3D Audio

As the availability of multichannel and 3D sound systems increases, so will the demand for the diffusion (upmixing) of stereo and 5.1 channel recorded audio to these larger, more immersive systems. In the simplest case, this may be taking mono or stereo audio and making it sound as if it was originally recorded and mixed for 5.1 surround sound, for which there are currently many, though similar methods. The vast majority of these methods, however, are not designed to accommodate larger 16.1 - 22.2 systems, nor concert hall acoustic-adjustment systems, which may employ several dozens channels. Although faithful to their source, these methods may add little to the inherent flatness of the original, 2-dimensional recordings.

This proposal is for the evaluation of a completely new method for rendering stereo and 5.1 audio on 3D systems (with height channels), making stereo and 5.1 audio sound as if they were originally recorded and mixed for an arbitrarily large system. It would capitalize on the increased number of loudspeakers to mimic the acoustic complexities that take place in concert halls caused by instrumentalists moving their instruments during performance, resulting in dynamically changing sound directivity. After the listener-informed fine-tuning of the system, test subjects would be brought into a 24.2 channel 3D audio facility for comparison and discrimination tests as it is compared to two other methods currently vying for standardization; Dolby’s ‘Atmos’ and Auro Technologies’ ‘Auro3D’.

Aside from evaluating the effectiveness of these competing technologies and thus influencing the outcome of this most recent format war, the comparison to this novel method could contribute to its acceptance in the industry. As such, it may well become an integral part of home entertainment systems, movie theatre sound systems, and concert hall acoustic-adjustment systems, providing listeners with a new, heightened listening experience, even from older stereo and 5.1 recordings.