RME Audio ADI-2 Pro, User Manual

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User’s Guide ADI-2/4 Pro SE - v 1.0
24.2 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 ADI-2/4 Pro SE
’s clock mode is set to 'In-
ternal', all other devices must be set to ‘Slave’.
To cope with some situations which may arise in studio practice, defining a sync reference is
essential.
RME’s exclusive
SyncCheck technology enables an easy to use check and display of
the current clock status. In the State Overview screen the column SYNC will show for all digital
inputs whether there is a valid signal (Lock, No Lock) for the optical input, or if there is a valid
and
synchronous signal (Sync). See chapter 15.3.
The SRC (Sample Rate Converter) can be used to de-couple the clocking, allowing to use more
than one clock master in a digital setup. See chapter 8.6 for details.
Under WDM the ADI-2/4 Pro SE will (has to)
set the sample rate. Therefore the error shown
to the right can occur. An AES, SPDIF or
ADAT signal with a sample rate of 48 kHz is used as sync source, but Windows audio had been
set to 44100 Hz before. The red color of the text label signals the error condition, and prompts
the user to set 48000 Hz manually as sample rate.
25. Operation and Usage
25.1 Playback
In the audio application being used, ADI-2/4 Pro SE must be selected as output device. It can
often be found in the
Options, Preferences or Settings menus, as Playback Device, Audio Devices
etc.
Increasing the number and/or size of audio buffers in the application (WDM) or the RME Settings
dialog (ASIO) may prevent the audio signal from breaking up, but also increases latency i.e. out-
put is delayed.
Please note that currently Windows WDM is limited to 384 kHz. 768 kHz can only be used via
ASIO.
Note: Since Vista the audio application can no longer control the sample rate under WDM. There-
fore the driver of the ADI-2/4 Pro SE includes a way to set the sample rate globally for all WDM
devices, found within the Settings dialog. See chapter 24.1.
!