Ambisonic Revival

All but forgotten in the field of surround sound are the efforts of UK classical music label Nimbus Records. More than 25 years ago, Nimbus recorded with Peter Fellgett and Michael Gerzon's two-channel–compatible, matrixed UHJ Ambisonic Surround system, using multi-capsule Calrec Soundfield microphones. Other labels, including Unicorn-Kanchana, also supported Ambisonic, releasing such rarities as a UHJ Ambisonic recording of the soundtrack to North By Northwest on LP. Playback decoders were available from the UK's National Research and Development Council (NRDC) and speaker manufacturer IMF. As timing would have it, the Ambisonic releases appeared when users could still recall the unfortunate experience of 1970s quadraphony, and Dolby Digital was still some years off. However, those who have heard proper demonstrations maintain that the UHJ Ambisonic technique remains the most convincing surround-sound format ever.

Now, well into the multichannel era, Nimbus has announced the release of a set of surround-music titles on DVD-Audio featuring DTS surround sound. Dubbed the Surroundyourselfwith series, it will present highlights from Nimbus' extensive catalog of Ambisonic recordings, dating back to the 1970s. Nimbus used the newly released DTS Pro Series Surround Encoder to create the DTS recordings.

A British invention, the Ambisonic technology recorded a 360-degree soundfield using a single-point microphone with four (later eight) capsules. This soundfield was then UHJ-encoded to provide a two-channel stereo-compatible signal, and decoded back to four-channel surround with the appropriate equipment. A full eight-channel rig used ceiling and floor speakers. Nimbus has been recording with Ambisonic for more than 30 years; before the company played a leading role as an independent manufacturer of CDs, its earliest Ambisonic releases appeared on LP. (Nimbus built the first CD factory in the UK.)

Although Ambisonic was not a commercial success, Nimbus continued to use the system, maintaining that it produced "the most natural recordings in keeping with the principles of true performance." Now the company is enjoying belated payback with the widespread domestic use of surround sound, courtesy the success of home-theater systems. The reissue of Nimbus' Ambisonic recordings on the DVD-A format is a natural response.

The reissues will adhere to the original four-channel playback format, which also adheres to DTS's philosophy: to "provide sound in keeping with an artist's original intent." "[This] fits well with Nimbus' own fundamental belief that their music recordings sound better in surround," said Gerben Van Duyl, director of business development for consumer content, DTS Europe. "By releasing the Surroundyourselfwith series with DTS surround sound, many people will hear these recordings for the first time the way they were originally meant to be heard."

Nimbus will launch the series with five discs: compilations of music by Elgar, Beethoven, Schubert, and Rachmaninoff, as well as a disc of American Classics by Sousa, Copland, and Barber. Future releases will include Indian classical music, flamenco from guitar player Paco Peña, Mendelssohn's incidental music, and the essential recordings of Enrico Caruso. Nimbus has more than 1000 titles in its back catalog; surround-sound enthusiasts can finally look forward to a steady flow of beautifully recorded material with which to exercise their multichannel systems.