User`s guide

User’s Guide ADI-8 QS © RME
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12.2 ADAT Optical
The ADI-8 QS provides two digital inputs and outputs in ADAT optical format. Using sample
rates up to 48 kHz only the port labeled MAIN is relevant for operation. Higher sample rates
than 48 kHz are realized by sample multiplexing. When using more than four channels at Dou-
ble Speed or two channels at Quad Speed, the port labeled AUX has to be used as well.
The ADAT optical inputs of the ADI-8 QS use RME's unsurpassed Bitclock PLL, which prevents
clicks and drop outs even in extreme varipitch operation, and guarantees a fast and low jitter
lock to the digital input signal. A usual TOSLINK cable is sufficient for connection.
In Single Speed mode both outputs carry the same audio data. Therefore the output signal can
be sent to two devices at the same time.
In standard operation the ADAT outputs carry the converted analog input signal. When activat-
ing the option Digital to Digital in the Setup menu the currently chosen digital input data is pre-
sent at the outputs instead, see chapter 9.15.
The ADAT outputs can be used in parallel to the AES outputs at up to 192 kHz, but in QS mode
only channels 1 to 4 will be available.
ADAT MAIN
Interface for the first or only device sending/receiving an ADAT signal. Carries the channels 1 to
8. In S/MUX mode (Double Speed), this port carries the channels 1 to 4. In S/MUX4 mode
(Quad Speed) this port carries channels 1 and 2.
ADAT AUX
Additional port for a transmission of channels 5 to 8 in S/MUX mode, or 3 and 4 in S/MUX4
mode.
With signals encoded as S/MUX, the Clock Section (STATE) has to be switched into DS mode
manually, depending on the current application. Each port carries the data of 4 channels only,
for up to 8 channels MAIN and AUX have to be used.
With signals encoded as S/MUX4, the Clock Section (STATE) has to be switched into QS mode
manually, depending on the current application. Each port carries the data of 2 channels only,
for up to 4 channels MAIN and AUX have to be used.