Ambisonic Surround Sound

Ambisonics is Dead: Long Live Ambisonics!

For a whirlwind tour of audio technology, read this article by John Whiting. It is reproduced with permission.

Frequently Asked Questions

If you want to know what is Ambisonic Surround Sound, read the FAQ. The latest version is 2.8, and was released on 21 January 1998.

You can also read the complete FAQ on one page. The complete FAQ is also available as an eBook (ePub) file, an eBook (Kindle) file, and a PDF file. Previous versions of the FAQ are available in an archive.

Why Ambisonic Surround Sound?

The three facets of a sound field and their reproduction.

An Experiment into Pair-Wise Mixing and Channel Separation

Equipment required: A stereo CD and something to play it on.

UHJ Discography

A discography of UHJ encoded recordings is available on Mark Anderson's Surround Discography Web page. The UHJ discography was originally compiled by Eero Aro and is being maintained by Mark.

Glossary

An Ambisonic glossary is available. This was written by Dr Geoffrey Barton and originally published in MultiChannelSound Review. It is reproduced with permission.

Spherical Harmonic Components

With Ambisonics, a sound field is decomposed into spherical harmonic components, termed W, X, Y and Z. These are collectively called B-Format. The Quantum Chemistry Group, Universidad de Oviedo, Spain, have produced some excellent images to illustrate these. They are reproduced with permission.

Ambisonic Bibliography

A bibliography of publications about Ambisonics and related matters compiled by the late Michael A Gerzon, the "Brains" behind Ambisonics, and others is available.

Want to sell?

If you have a used Ambisonic/UHJ decoder, in any condition, which you would like to sell then I would like to buy. This includes decoders from Audio+Design/Cepiar, Abacoid, IMF Electronics, etc.

Help for DIY enthusiasts

Design equations for people working on home build projects. Also, see the "Elsewhere" links at the bottom of this page.

Elsewhere

More Help for DIY Enthusiasts

Apart from my page described above, help for people designing or building their own Ambisonic equipment includes:

Ambisonic microphone and UHJ encoder, UHJ decoder, joystick controlled pan-rotate, by Henry - disappeared
The Sound Thief, an Ambisonic microphone by Lalila - disappeared, but available on the Wayback Machine
An Ambisonic microphone by Nick Mariette
An Ambisonic microphone by Paul Doornbusch
An Ambisonic microphone by Dan Hemingson - disappeared
A digital UHJ decoder by Bruce Wiggins

Resources

Articles and other resources on Ambisonics.

Ambisonics on Wikipedia
Ambisonia.com, a repository for surround sound recordings and compositions
Ambisonic.Net, maintained by Richard Elen
On-line reprints from Larry Clifton's MultiChannelSound Review magazine - disappeared
SoundField Limited, surround sound recordings - disappeared
Ambiosonic UHJ Audio, information useful to owners of the Troy TA 110P car decoder, Onkyo TX-SV909PRO A/V Receiver, and Integrex decoder
Minim Decoders, information useful to owners of the AD 7 and AD 10
IMF Electronics Decoders, information useful to owners of the D20B

File Formats

File formats for downloadable Ambisonic audio files:

Official file format for downloadable B-Format files, the ".amb" format
Official file format for downloadable two-channel UHJ files, the ".uhj" format
Proposed file format for downloadable G-Format files, the ".amg" format
Proposed chunk for multi-channel WAVE-EX sound files to indicate the intended positions (azimuths and elevations) of the speakers.

Research

Research into Ambisonic Surround Sound is being conducted by a few groups around the world, including:

Richard Furse - disappeared
Music Technology Group, University of York, United Kingdom - disappeared
The PhD of Jerome Daniel (mostly in French), University of Paris, France
Audio ResearchGroup, University of Waterloo, Canada - disappeared
University of Parma, Italy

Manufacturers

Manufactures of equipment and systems for professional and domestic Ambisonic processing include:

Domestic Ambisonic decoders
- Meridian Audio Limited
- Cantares
Ambisonic software
- B-Format Encoder and decoder VST plugins - disappeared
- UNreal-time B-Format to UHJ encoder
- Ambisonic VST plug ins; mixing desk, decoder, panner, player, recorder - disappeared
- Second-order Ambisonic tools for Csound along with a tutorial for beginners
Ambisonic microphones
- SoundField Limited
- Core Sound TetraMic® and OctoMic®
- Brahma microphones
- spcmic third-order mic
- Sennheiser AMBEO
- Audeze VR Tetrahedral mic - disappeared
- Oktava MK-012AM - disappeared
- mh acoustics LLC
- AGM Digital Arts GmbH
- Soyuz 013-Ambisonic