RME Audio Hammerfall Multiface II, User Manual

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User's Guide HDSP System Multiface II
© RME
I/O Box State
This field displays the current state of the I/O-box.
Error: I/O-box not connected or missing power
Detected: The interface has found an I/O-box and tries to load the firmware
Connected: Communication between interface and I/O-box operates correctly
Disconnected: Communication between interface and I/O-box has been interrupted, I/O-
box continues operation
Word Clock Out
The word clock output signal usually equals the current sample rate. Selecting Single Speed
causes the output signal to always stay within the range of 32 kHz to 48 kHz. So at 96 kHz
sample rate, the output word clock is 48 kHz.
Clock Mode
The unit can be configured to use its internal clock source (Master), or the clock source pre-
defined via
Pref. Sync Ref (AutoSync).
Pref. Sync Ref.
Used to pre-select the desired clock source. If the selected source isn't available, the unit will
change to the next available one. The current clock source and sample rate is displayed in the
AutoSync Ref display.
The automatic clock selection checks and changes between the clock sources Word Clock,
ADAT and SPDIF.
System Clock
Shows the current clock state of the HDSP system. The system is either Master (using its own
clock) or Slave (see AutoSync Ref).
11.2 Clock Modes - Synchronisation
In the digital world, all devices are either the ‘Master’ (clock source) or a ‘Slave’ synchronized
to the master. Whenever several devices are linked within a system, there must always be a
single master clock. The Hammerfall DSP’s intelligent clock control is very user-friendly, being
able to switch between clock modes automatically. Selecting
AutoSync will activate this mode.
In AutoSync mode, the system constantly scans all digital inputs for a valid signal. If this signal
corresponds with the current playback sample rate, the card switches from the internal quartz
(AutoSync Ref displays 'Master') to a clock generated from the input signal (AutoSync Ref dis-
plays 'Slave'). This allows on-the-fly recording, even during playback, without having to syn-
chronize the card to the input signal first. It also allows immediate playback at any sample rate
without having to reconfigure the card.
AutoSync guarantees that normal record and record-while-play will always work correctly. In
certain cases however, e.g. when the inputs and outputs of a DAT machine are connected di-
rectly to the Hammerfall DSP
,
AutoSync may cause feedback in the digital carrier, so synchro-
nization breaks down. To remedy this, switch the HDSP’s clock mode over to 'Master'.
Remember that a digital system can only have one master! If the HDSP’s clock mode is
set to 'Master', all other devices must be set to ‘Slave’.