Innes Corporation Pty Ltd
3/38 Leighton Pl
Hornsby, NSW 2077, Australia
Phone: +61 2 9987 0499
Fax: +61 2 9987 0599
E-mail:
Website: http://www.innescorp.com.au
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Auricon 2.2 & 4.1 Manual
Extended Bit Depth Audio
Traditionally, PC-based audio capture and playback has been restricted to either 8 bit or 16 bit
encoding, with the WAVE_FORMAT_PCM descriptor used to define the audio parameters such
as samples per second, bits per sample and number of channels.
With the advent of 24 bit A/D and D/A converters, there was a need to support extended bit
depth. To achieve this, Microsoft introduced a new data format descriptor called
WAVE_FORMAT_EXTENSIBLE. This provides additional information, including the number of
valid bits per sample and support for specifying channel placement in multichannel streams.
The WAVE_FORMAT_EXTENSIBLE descriptor may be used in place of the normal
WAVE_FORMAT_PCM in setting up playback and recording through either the Winmm (wave)
API or the DirectSound API. For further information refer to the Microsoft DirectX 8
documentation. Note that the Auricon’s NT4 driver does not support extended bit depth.
Some audio editing applications, such as Syntrillium’s Cooledit 2000 and Adobe Audition,
support extended bit depth audio and work well with the Auricon using 24 or 32 bit recording.
