RME DSP System Multiface - Manual (Page 18)

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User's Guide HDSP System Multiface II © RME
9.3 Notes on WDM
The driver offers a WDM streaming device per stereo pair, like HDSP Multiface (1+2). WDM
streaming is Microsoft's current driver and audio system, directly embedded into the operating
system. WDM streaming is hardly usable for professional music purposes, as all data is proc-
essed by the so called Kernel Mixer, causing a latency of at least 30 ms. Additionally, WDM can
perform sample rate conversions unnoticed, cause offsets between record and playback data,
block channels unintentionally and much more.
Several programs do not offer any direct device selection. Instead they use the playback device
selected in Windows under
XP: <Control Panel/ Sounds and Multimedia/ Audio>
Vista/7: <Control Panel/ Sound/ Playback>
The program Sonar from Cakewalk is unique in many ways. Sonar uses the so called WDM
Kernel Streaming, bypassing the WDM mixer, thus achieves a similar performance to ASIO.
Because of the driver's multichannel streaming ability Sonar not only finds the stereo device
mentioned above, but also the 8-channel interleaved devices, and adds the channel number at
the end:
HDSP Multiface (1+2) is the first stereo device
HDSP Multiface (3+4) is the next stereo device
HDSP Multiface (1+2) 3/4 are the channels 3/4 of the first 8-channel interleaved device.
It is not recommended to use these special interleaved devices. Also note that it is not possible
to use one stereo channel twice (the basic and the interleaved device).
Multi-Channel using WDM
The WDM Streaming device Loudspeaker (Analog 1+2) of the RME driver can operate as usual
stereo device, or as up to 8-channel device.
An 8-channel playback using the Windows Media Player requires the speaker setup 7.1 Sur-
round. Configure as follows:
XP: >Control Panel /Sounds and Multimedia /Audio /Volume /Speaker Settings /Advanced <
Vista/7: >Control Panel /Sound /Playback /Loudspeaker /Configure <