User's Guide
DIGI32 PRO © RME
11
10.2 Synchronisation
DIGI32 PRO
works exclusively in slave mode when recording. The card continously sear-
ches for a valid input signal at the active input. As soon as this matches the actual sample fre-
quency the card switches from the internal reference (quarz) to the clock generated out of the
input signal (PLL). So starting a recording on-the-fly is possible (also anytime during playback
thanks to Full Duplex) without first having to synchronize the card to the input signal.
In order to connect more than one
DIGI32 PRO
to a digital mixing desk they must all get
the same clock(ed input signal). This is easy to achieve: just connect at least one input of
each card to one output of the mixing desk.
But the slave mode however does not allow 'local loop-back' operation. For example: you play
back a wave file, send it through a digital effect device and immediately send it back to the com-
puter. Despite Full Duplex this is not possible because in this looped mode the card as well as
the external device synchronize themselve to their own input. A master or clock reference is
missing. Help is obtained either by the insertion of a digital mixing desk or by using two
DIGI32 PRO
where the transmitting card is to be used without (!) an input signal. Hint:
Simply set the input of this card to an unconnected one.
In most cases 'local loop-back' can be realized. A DAT used as A-D-A-Converter whose digital
output is connected to the input of the
DIGI32 PRO
also leads to a loop and a loss of the
digital carrier. But after deactivating 'AutoSync' such a loop requiring no clock master is possible
even with other devices, because the DAT is not working in Full Duplex mode.
More informations on this subject can be found in the HTML document 'sync.htm', located in the
directory
\rmeaudio.com\english\techinfo
on the RME Driver CD.
10.3 Varispeed
Thanks to the described AutoSync technology and a lightning fast PLL
DIGI32 PRO
is able
not only to operate with usual sample frequencies, but with every frequency in the range of 25
kHz to 105 kHz. The digital input serves as synchronisation source. Please note that at the start
of a record or playback a valid sample frequency (32 kHz, 44,1 kHz, 48 kHz, 64 kHz, 88,2 kHz,
96 kHz) has to be fed. When started the sample frequency can be pitched to whatever is nee-
ded,
DIGI32 PRO
will follow theses changes immediately.
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