This is the new native audio format for Windows2000 and XP. A preliminary level of support was  incorporated into Windows98 Second Edition.

The final html version of  the specification can be read here.
Note that the specification covers both WAVE file formats and the streaming format for recording and playback.
It is the required format for all high-resolution (> 16bit) and multi-channel audio (> stereo) streaming.
The level of support also depends partly on the soundcard driver.


Here are some four-channel soundfiles in the new format. I hope to post more examples soon (space permitting), and also that other sites will appear, as other developers complete the software required to handle the new format. CDP has published a free Multi-Channel Toolkit (WIN32 console), which includes programs to  play multi-channel files using a multi-channel  device (MME or DirectSound), and a program to create the quadraphonic pan illustrated above.

Example 1: from Microsoft
Speech idents, in LCRS surround format(44100Hz,16bit, 3.83 secs)
Wave_ex1.zip (291KB)

example 2: from me! (illustrated above)
Drum, panned ambisonically in a circle in quad format (LF,RF,LR,RR) (22050Hz,16bit, 4.78 secs)
(also contains the PEAK chunk)  To comply with the requirements of B-Format, these speakers must be located at the corners of a square.
Drmapan.zip (660KB)

example 3: an example in the new Ambisonic B-format subtype of WAVE-FORMAT-EXTENSIBLE.
As Example 2 above, but in First-Order B-Format (i.e. prior to decoding to speakers), and at sr=44100 .
Note  that this is a horizontal-only encoding, so  that the Z channel (representing height) is empty.
Drmpnaxb.zip (1.65MB). The player programs in the CDP Toolkit will recognize the format and automatically decode it to 4 speakers.

Details of the B-Format specialization of WAVE-EX can be read here.

NEW!   Simple Windows media player "bfplayer" to render WAVE-EX B-Format files.

(Updated December 7 2005)

This supports the recently proposed alternative file extension .amb and .ambi.
It will also play generic multi-channel files (WAVE and AIFF). Uses DirectSound for audio output.
This is only intended as a short-term facility, until a new Open-Source cross-platform player is available.
This version will decode both 3 and 4-channel B-Format files,  to a horizontal quad layout. This may or may not be expanded over time. The new file formats .amb and .wxyz are supported.
It requires (surprise!) a single multi-channel interleaved audio device, which must be set as the system default.
The program does not offer the  means to select a device.

This has been developed and tested on Windows XP, should work on Win2K. Probably will not work on Win98SE. 
There may well be embarrassing and primitive bugs! if you find any, please email me (see my home page).
This is a self-contained application - just unzip and run; will not touch Windows system folders.
bfplayer097.zip (310KB).

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Page last updated 16th November 2005