RME Audio Hammerfall HDSPe RayDAT, User Manual

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User's Guide HDSPe RayDAT
© RME
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).
Input Status / Pref. Sync Ref
SyncCheck
indicates whether there is a valid signal (Lock, No Lock) for each input (ADAT 1-4,
SPDIF, AES, Word/TCO and internal Sync), or if there is a valid and synchronous signal (Sync).
In the third row the sample rate measured by the hardware is shown.
The fourth row is used to pre-select the desired clock source. If the selected source isn't avail-
able, the unit will change to the next available one automatically. The current clock source and
sample rate is displayed in the
System Clock field.
The automatic clock selection
checks and changes between the
clock sources ADAT1-4, AES,
SPDIF, Word/TCO and Sync
Internal.
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.
System Clock
Shows the current clock state of
the HDSPe system. The system is
either Master (using its own clock)
or Slave.
19.2 Settings dialog - DDS
Usually soundcards and audio interfaces generate their internal clock (master mode) by a
quartz. Therefore the internal clock can be set to 44.1 kHz or 48 kHz, but not to a value in
between. SteadyClock, RME's sensational Low Jitter Clock System, is based on a
Direct Digital
Synthesizer (DDS). This superior circuitry can generate nearly any frequency with highest pre-
cision.
DDS has been implemented into the HDSPe RayDAT with regard to the needs of professional
video applications, as well as to maximum flexibility. The dialog DDS includes both a list of typi-
cal video frequencies (so called pull up/pull down at 0.1% and 4%) and two faders, which allow
to freely change the basic sample rate in steps of 1 Hz (!).
The DDS dialog requires the HDSPe RayDAT to be in clock mode Master! The frequency
setting will only be applied to this one specific card!
Changing the sample rate in bigger steps during record/playback often results in a loss of
audio, or brings up warning messages of the audio software. Therefore the desired sample
rate should be set at least coarsely before starting the software.