User Manual

16
User's Guide HDSPe RayDAT © RME
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).
System Clock
Shows the current clock state of the HDSPe system. The system is either Master (using its own
clock) or Slave.
About
This tab includes information about the driver and the card’s firmware version.
Lock Registry uses a password to prevent changes of the settings stored in the registry. All
settings are still changeable temporarily. As the settings are always loaded from the registry
when starting the computer, this method provides an easy way to define a specific initial state of
the HDSP system.
11.2 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 be-
tween. 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 (!).
Application examples
DDS allows for a simultaneous change of speed and tune during record and playback. From
alignment to other sources up to creative effects – everything is possible..
DDS allows to intentionally de-tune the complete DAW. This way, the DAW can match instru-
ments which have a wrong or unchangeable tuning.
DDS allows to define a specific sample rate. This feature can be is useful in case the system
randomly changes the sample rate – for unknown reasons. It also prevents a change from Dou-
ble Speed (96 kHz) to Single Speed (48 kHz), which would cause configuration and routing
problems by the changed amount of ADAT channels.
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.