User Manual

User's Guide Fireface 800 © RME
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11. Operation under ASIO 2.0
11.1 General
We will use Steinberg’s Cubase VST as an example throughout this chapter. All information
provided can easily be adaptated to other programs.
Start the ASIO software and
select ‘System’ from the Audio
menu. Select 'ASIO Fireface' as
the audio I/O device. The 'ASIO
system control' button opens
the Fireface's Settings dialog
(see chapter 8, Configuration).
Fireface 800 supports simulta-
neous record and playback of
SPDIF audio data together with
record and playback in ADAT
format. Please note that the
external SPDIF device has to
be running in sync, otherwise
recordings will be corrupted.
Fireface 800 supports 'ASIO
Direct Monitoring' (ADM).
Please note that currently Nu-
endo, Cubase and Logic do not support ADM completely error-free.
When the sample frequency is set to 88.2 or 96 kHz, the number of ASIO ADAT channels is
reduced to 4 per ADAT port. At a sample rate of 176.4 or 192 kHz (Quad Speed Mode) the
ADAT I/O is no longer available. Nevertheless it will send out a synchronized ADAT signal at a
quarter of the sample rate. The ASIO driver corrects the number of channels when changing
from Single to Double or Quad Speed. The channel routing of both ADAT ports is shown in
chapter 31.
Some programs do not recognize the dynamic change of the number of ADAT channels, there-
fore do not operate correctly in Double and Quad Speed mode. A workaround is to use DDS.
After having set the desired sample rate, the ASIO software recognizes the correct number of
I/O channels directly when started.
11.2 Known Problems
If a computer does not provide sufficient CPU-power and/or sufficient PCI-bus transfer rates,
then drop outs, crackling and noise will appear. We recommend to deactivate all PlugIns to
verify that these are not the reason for such effects.
Unfortunately some newer UltraATA66 and UltraATA100 hard disk controllers (also Raid con-
trollers) seem to violate the PCI specs. To achieve the highest throughput they hog the PCI
bus, even in their default setting. Thus when working with low latencies heavy drop outs (clicks)
are heard. Try to solve this problem by changing the default setting of the controller (for exam-
ple by reducing the 'PCI Bus Utilization').
The above note on PCI is not an error in this manual: so far all FireWire controllers are placed
on the PCI bus. Therefore the same problems known from RMEs PCI cards might also show up
with the Fireface 800.