User Manual

User's Guide HDSP System HDSP 9652 © RME
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The HDSP 9652’s word clock input can be high-impedance or terminated internally, ensuring
maximum flexibility. If termination is necessary (e.g. because HDSP 9652 is the last device in
the chain), bring jumper X105 on the Expansion Board into position 75 Ohm.
In case the HDSP 9652 resides within a chain of devices receiving word clock, plug a T-adapter
into its BNC input jack, and the cable supplying the word clock signal to one end of the adapter.
Connect the free end to the next device in the chain via a further BNC cable. Remove jumper
X105 from the Expansion Board. The last device in the chain should be terminated using an-
other T-adapter and a 75 Ohm resistor (available as short BNC plug). Of course devices with
internal termination do not need T-adaptor and terminator plug.
23.3 Operation
The HDSP 9652's word clock input is active when Pref. Sync Ref in the Settings dialog has
been set to Word Clock, the clock mode AutoSync has been activated, and a valid word clock
signal is present. The signal at the BNC input can be Single or Double Speed, the Hammerfall
DSP automatically adapts to it. As soon as there is a valid signal at the BNC jack, AutoSync Ref
will display Word. This message has the same function as the green Lock LED, but appears on
the monitor, i.e. the user can check immediately whether a valid word clock signal is present
and is currently being used.
In the line Freq., the AutoSync Ref shows the frequency of the reference signal, measured by
the hardware. In this case the frequency of the current word clock signal is measured and dis-
played.
The word clock output of the Hammerfall DSP is constantly active, providing the current sample
frequency as word clock signal. As a result, in Master mode the provided word clock is defined
by the currently used software. In Slave mode, the provided frequency is identical to the one
present at the currently chosen clock input. When the current clock signal fails, the Hammerfall
DSP switches to Master mode and adjusts itself to the next, best matching frequency (44.1 kHz,
48 kHz etc.).