This is one of a series of pages detailing attempts to play Ambisonic sound on cheap everyday equipment. This is not the ideal way to do it, but it does allow for experimentation. The faltering steps reported here are offered as one person's experience not as suggestions of how anything should be done!!
Currently there seems no way to make Audacity recognise channels as grouped (except for stereo!).
Pantophonic recordings (a full 360 degree horizontal soundstage) may be recorded with or without a 'height track' (Z).
Periphonic recordings (fully 3-dimensional) have (at least four tracks: WXYZ).
Both to discover what you have and to convert WXY to WXYZ you can open them in Audacity.
(There is now a Ambman utility ambman --wxy2amb that will do this conversion without a need to open the file.)
You can save your files as Wave Format Extensible (which is almost a .amb file) by doing the following:
Some horrible presumptions will be recorded in the file header (e.g. if it is a first order file, it will map the tracks to 'quadrophonic' speaker positions … !!). Such metadata does not affect how you use the file, it is though rather anti-social for file-exchange and archiving. I have written a utility (wav2amb) which corrects the headers as well as one ambinfo) that displays them.
September 2007 (last updated October 2007).
Copyright © 2007 Michael Chapman.