Limit Bandwidth - RME Audio Fireface 800 User Manual

At 88.2 or 96 kHz: If the ADAT input has been selected in Pref Sync Ref, the sample frequency
shown in the SPDIF Freq. field differs from the one shown in AutoSync Ref. The unit automati-
cally switches to S/MUX mode here, because ADAT optical inputs and outputs are only speci-
fied up to 48 kHz. Data from/to a single input/output is spread over two channels, the internal
frequency stays at 44.1 or 48 kHz. In such cases, the ADAT sample frequency is only half the
SPDIF frequency.

11.5 Limit Bandwidth

This option allows to reduce the amount of bandwidth used on the FireWire bus. A typical ex-
ample is the use of the Fireface with a laptop. Only in rare cases both ADAT ports are needed,
in many cases even both stay unused. The option Analog+SPDIF will reduce the amount of
constantly (!) transferred data from around 5 MByte (10 in both directions) to only 2 MByte (4 in
both directions). The FireWire connection will be more stable, reliable and robust, leaving addi-
tional bandwidth for other devices. At the same time the CPU and system load is reduced, as
less channels have to be processed and to be transferred. In TotalMix, the deactivated software
playback channels will be replaced with empty plates. More details are found in chapter 35.4.
Available Settings
All channels (default) activates all 28 input and output channels.
Analog + SPDIF + ADAT1 disables channels 21–28 (ADAT2).
Analog + SPDIF activates all 10 analog channels plus SPDIF.
Analog 1-8 activates only the first eight analog channels.
User's Guide Fireface 800 © RME
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