Innes Corporation Pty Ltd
3/38 Leighton Pl
Hornsby, NSW 2077, Australia
Phone: +61 2 9987 0499
Fax: +61 2 9987 0599
E-mail:
sales@innescorp.com.au
Website: http://www.innescorp.com.au
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Auricon 2.2 & 4.1 Manual
Output Mixing
(Windows 98/ME/2000/XP/Server 2003/Vista)
The Auricon presents itself to the operating system as multiple independent wave output
devices. Each device can support any number of output streams, courtesy of the Windows
Kernel Mixer.
The topology of each output device is shown below. It consists of the kernel mixer that
combines any number of individual waveOut and DirectSound audio streams (applying
sampling rate conversion if need be), followed by the “Wave Out” level control. Midi and CD
streams are also added at this point. This is then followed by the Auricon mixer (implemented in
the on-card DSP) that adds the input sources (two if configured as stereo and four if configured
as mono), master level control and peakmeter. All level controls include a mute control as well.
Wave Out
Midi
CD
Line Input 1
Line Input 2
Playback Master
Analog Output
Analog Input 1
Analog Input 2
Software Synth
Redbook
waveOut stream
waveOut stream
DirectSound stream
DirectSound stream
Any number of waveOut streams
Any number of DirectSound streams
Windows Kernel Mixer
Line Input 3
Line Input 4
Analog Input 3
Analog Input 4
Inputs 3 and 4 only present in mono configuration
Auricon Mixer
Each waveOut stream is created by opening an instance of the waveOut device. Each
DirectSound stream corresponds to a DirectSoundBuffer object. There is no limit to the number
of streams that can be opened on each device. Note that with versions of Windows prior to
Vista, only DirectSound streams have individual level controls – these are set using the
DirectSoundBuffer.SetVolume method. The Windows documentation suggests that
waveOutSetVolume should also adjust the level of individual waveOut streams but this doesn’t
seem to work - instead changing the level of one stream actually changes the setting of the
kernel mixer’s “Wave Out” fader and thus affects the level of every stream on that device.
