RME Audio Hammerfall HDSPe AIO, User Manual

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User's Guide HDSPe AIO
© RME
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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
(
System Clock - Mode Master ) to a clock generated from the input signal ( System Clock - Mode
Slave ). A difference to usual slave behaviour is that when the input signal is lost the card will
immediately switch back to the internal clock, into Master mode.
With the HDSPe AIO all inputs operate simultaneously. However, as there is no input selector,
the HDSPe has to be told which of the signals is the sync reference (a digital device can only be
clocked from a
single source).
Via
Pref. Sync Ref (preferred synchronization reference) a preferred input can be defined. As
long as the card sees a valid signal there, this input will be designated as the sync source, oth-
erwise the other inputs will be scanned in turn. If none of the inputs are receiving a valid signal,
the card automatically switches clock mode to ‘Master’.
To cope with some situations
which may arise in studio prac-
tice, setting ‘Pref Sync Ref’ is
essential. One example: An
ADAT recorder is connected to
the ADAT input (ADAT immedi-
ately becomes the sync source)
and a CD player is connected to
the SPDIF input. Try recording
a few samples from the CD and
you will be disappointed. Few
CD players can be synchro-
nized. The samples will inevita-
bly be corrupted, because the
signal from the CD player is
read with the (wrong) clock from
the ADAT i.e. out of sync.
In this case, 'Pref Sync Ref'
should be temporarily set to
SPDIF.
RME’s exclusive
SyncCheck technology enables an easy to use check and display of the cur-
rent clock status. The status box labelled Input Status indicates whether no signal (‘No Lock’),
a valid signal (‘Lock’) or a valid and synchronous signal (‘Sync’) is present at each of the digital
clock source inputs.
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 SyncCheck, finally anyone can
master this common source of error, previously one of the most complex issues in the digital
studio world.
Thanks to its AutoSync technique and lightning fast PLLs, the HDSP is not only capable of han-
dling standard frequencies, but also any sample rate between 28 and 200 kHz.