User Manual

34
User's Guide Fireface UC © RME
17.5 Channel Count under Core Audio
The Fireface’s ADAT optical interface offers sample rates of up to 192 kHz using a standard
ADAT recorder. For this to work single-channel data is spread to two or four ADAT channels
using the Sample Multiplexing technique. This reduces the number of available ADAT channels
from 8 to 4 or 2.
It is not possible to change the number of Core Audio devices without a reboot of the computer.
Therefore whenever the Fireface UC changes into Double Speed (88.2/96 kHz) or Quad Speed
mode (176.4/192 kHz) all devices stay present, but become partly inactive.
Single Speed Double Speed Quad Speed
Fireface UC Analog 1 to 8 Fireface UC Analog 1 to 8 Fireface UC Analog 1 to 8
Fireface UC SPDIF L / R Fireface UC SPDIF L / R Fireface UC SPDIF L / R
Fireface UC ADAT 1 to 2 Fireface UC ADAT 1 to 2 Fireface UC ADAT 1 to 2
Fireface UC ADAT 3 to 4 Fireface UC ADAT 3 to 4 Fireface UC ADAT 3 to 4
Fireface UC ADAT 5 to 6 Fireface UC ADAT 5 to 6 Fireface UC ADAT 5 to 6
Fireface UC ADAT 7 to 8 Fireface UC ADAT 7 to 8 Fireface UC ADAT 7 to 8
17.6 Various Information
The driver of the Fireface UC requires at least Mac OS 10.5, as special USB functions are used
that are not available in older versions of the operating system.
Via >System Preferences/ Audio-MIDI Setup< the hardware can be configured for the system
wide usage. Programs that don't support card or channel selection will use the device selected
as Standard-Input and Standard-Output. (Soundstudio, Mplayer, Amplitube etc.).
In the lower part of the window, the audio hardware's capabilities are shown and can be
changed in some cases. On the record side no changes are possible. Programs that don't sup-
port channel selection will always use channels 1/2, the first stereo pair. To access other inputs,
use the following workaround with TotalMix: route the desired input signal to output channels
1/2. In the channel settings of outputs 1/2 activate Loopback. Result: the desired input signal is
now available at input channel 1/2, without further delay/latency.
Use Speaker Setup to freely configure the playback to all available channels. Even multichan-
nel playback (Surround, DVD Player) can be set up this way.