User Manual

User's Guide Babyface Pro © RME
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Clock Mode
Sample Rate
Used to set the current sample rate. This is the same setting as in the Audio MIDI Setup, just
added here for your convenience.
Clock Source
The unit can be configured to use its own clock (Internal = Master) or the digital input signal
(Optical = Slave). If the external source isn't available (Input Status No Lock), the unit will
change to the internal clock. The current clock source is displayed as Current.
Input Status
Indicates for the optical input whether there is a valid signal (Lock, No Lock), or if there is a valid
and synchronous signal (Sync). The third column shows the sample frequency detected by the
hardware (coarse recognition, 32 kHz, 44.1 kHz, 48 kHz etc.). In Clock Mode the clock refer-
ence is shown. See also chapter 26.1.
16.2 Clock Modes - Synchronization
In the digital world, all devices must be either Master (clock source) or Slave (clock receiver).
Whenever several devices are linked within a system, there must always be a single master
clock.
A digital system can only have one master! If the Babyface Pro’s clock mode is set to 'Inter-
nal', all other devices must be set to ‘Slave’.
The Babyface Pro utilizes a very user-friendly, intelligent clock control, called AutoSync. Se-
lecting Optical as Clock Source, the system constantly scans the digital input for a valid signal.
If any valid signal is found, the Babyface Pro switches from the internal quartz (Clock Mode –
Current Internal) to a clock extracted from the input signal (Clock Mode – Current ADAT or
SPDIF). The difference to a usual slave mode is that whenever the clock reference fails, the
system will automatically use its internal clock and operate in clock mode Master.
AutoSync guarantees that 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 directly to
the Babyface Pro, AutoSync may cause feedback in the digital carrier, so synchronization
breaks down. To solve this problem switch the Babyface Pro clock mode to Master (Clock
Source – Internal).
In some situations changing the clock mode can not be avoided. Example: A CD player is con-
nected to the SPDIF input. Try recording a few samples from the CD and you will be disap-
pointed - few CD players can be synchronized. The samples will inevitably be corrupted, be-
cause the signal from the CD player is read with the clock from the Babyface Pro, being out of
sync. In this case, the Clock Source should be set temporarily to Optical.
RME’s exclusive SyncCheck technology (first implemented in the Hammerfall) enables an easy
to use check and display of the current clock status. Input Status indicates whether there is a
valid signal (Lock, No Lock) for the optical input, or if there is a valid and synchronous signal
(Sync). In the field Clock Mode the clock reference is shown. See chapter 26.1.
In practice, SyncCheck provides the user with an easy way of checking whether all digital de-
vices connected to the system are properly configured. With AutoSync and SyncCheck, finally
anyone can master this common source of error, previously one of the most complex issues in
the digital studio world.