Multi-Client Operation - RME Audio Fireface 400 User Manual

12.5 Multi-client Operation

RME audio interfaces support multi-client operation. This means several programs can be used
at the same time. Also all formats, like ASIO, MME and GSIF can be used simultaneously. The
use of multi-client operation requires to follow two simple rules:
•
Multi-client operation requires identical sample rates!
I.e. it is not possible to use one software with 44.1 kHz and the other with 48 kHz.
•
Different software can not use the same channels at the same time.
If for example Cubase uses channels 1/2, this playback pair can't be used in Gigasam-
pler/Studio (GSIF) nor under MME (WaveLab etc.) anymore. This is no limitation at all, because
TotalMix allows any output routing, and with this a playback of multiple software on the same
hardware outputs. Note that the inputs can be used at the same time, as the driver sends the
data to all applications simultaneously.
ASIO-Multiclient
RME audio interfaces support ASIO multi-client operation. It is possible to use more than one
ASIO software at the same time. Again the sample rate has to be identical, and each software
has to use its own playback channels. Again the inputs can be used simultaneously.
RME's sophisticated tool DIGICheck is an exception to this rule. It operates like an ASIO host,
using a special technique to access playback channels already occupied. Therefore DIGICheck
is able to analyse and display playback data from any software, no matter which format the
software uses.
Multi-Client and Multi-Channel using WDM
The WDM Streaming devices of our driver can operate as usual stereo devices, or as 8-channel
devices. The option Interleaved in the Settings dialog determines the current mode.
Interleaved not active: The WDM devices operate as usual stereo devices. The multi-client op-
eration works as described above with WDM, ASIO, MME and GSIF.
Interleaved active: The WDM devices can also be used as 8-channel devices. Unfortunately the
Kernel Mixer, active with any WDM playback, then always occupies and blocks 8 channels at
once, even when WaveLab or the Media Player perform just a stereo playback (2 channels).
So:
If any stereo pair within an 8-channel group is used, the whole 8-channel group is blocked.
As a result, no second stereo pair of this group can be used, neither with ASIO, MME nor
GSIF.
The Fireface provides two 8-channel groups: the analog inputs 1 to 8 and the ADAT port.
Starting MME, ASIO or GSIF playback on any of the stereo pairs of an 8-channel group prior to
starting a WDM playback will prevent the Kernel Mixer from opening the 8-channel device, as
two of its channels are already in use. The Kernel Mixer then automatically reverts to open a
stereo device for a stereo playback.
Software which is capable of using more than one MME device usually uses the (WDM-) MME
devices. A surround playback via Media Player should be possible without the need of recon-
figuration. That's why the mode Interleaved is activated in the Settings dialog by default.
User's Guide Fireface 400 © RME
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