Operation Under Asio; General; Known Problems - RME Audio Hammerfall DSP System MADI User Manual

13. Operation under ASIO

13.1 General

Start the ASIO software
and select ASIO Hammer-
fall DSP as the audio I/O
device. The 'ASIO system
control' button opens the
HDSP's Settings dialog
(see chapter 11, Configu-
ration).
At a sample rate of 88.2 or
96 kHz (Double Speed
mode), the number of
channels available at the
MADI input and output is
halved.

13.2 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.
Additional hard disk controllers, both on-board and PCI based, often 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 example by reducing the 'PCI Bus Utilization').
Another common source of trouble is incorrect synchronization. ASIO does not support asyn-
chronous operation, which means that the input and output signals not only have to use the
same sample frequency, but also have to be in sync. All devices connected to the Hammerfall
DSP must be properly configured for Full Duplex operation. As long as SyncCheck in the Set-
tings dialog displays Lock instead of Sync, the devices have not been set up properly!
When using more than one HDSP system all units have to be in sync, see chapter 15. Else a
periodically repeated noise will be heard.
Hammerfall DSP supports ASIO Direct Monitoring (ADM). Please note that currently Nuendo,
Cubase and Logic either do not support ADM completely or error-free. A well known problem is
the wrong operation of a stereo channel's panorama function.
In case of a drift between audio and MIDI, or in case of a fixed deviation (MIDI notes placed
close before or behind the correct position), the settings in Cubase/Nuendo have to be
changed. At the time of print the option 'Use System Timestamp' should be activated. The
HDSP MADI supports both MME MIDI and DirectMusic MIDI. It depends on the used applica-
tion which one will work better.
User's Guide HDSP MADI © RME
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