RME OCTAMIC II [19/32] Adat optical

User’s Guide OctaMic II © RME

AES/EBU Sync

The input AES 1 (channel 1/2) found on the D-sub connector can not be used for audio with the

OctaMic II, but as clock source. The input is transformer-balanced and ground-free. Thanks to a

highly sensitive input stage, a SPDIF signal can also be fed by using a simple cable adapter

phono/XLR (see above).

Pinout of the D-sub connector, Inputs

Signal In

1/2+

1/2-

3/4+

3/4-

5/6+

5/6-

7/8+

7/8-

D-sub 24 12 10 23 21 9 7 20

GND is connected to pins 2, 5, 8, 11, 16, 19, 22, 25. Pin 13 is not connected.

11.2 ADAT Optical

The OctaMic II provides two digital outputs in ADAT optical format. In Single Speed mode both

outputs carry the same audio data. With this it is possible to distribute the output signal to two

devices (2 x ADAT splitter).

As the ADAT optical signal is physically specified up to 48 kHz only, the OctaMic II automati-

cally activates Sample Split mode (S/MUX) at 88.2 and 96 kHz, distributing the data of one

channel to two output channels. The internal frequency stays at 44.1/48 kHz. Therefore the

sample clock at the ADAT outputs is only half the frequency of the AES outputs. As interesting

as this is – you don't need to think about it. 96 kHz capable ADAT hardware, like all current

RME digital interfaces, re-combine the data automatically. The user (and the DAW software)

does not see any split data, but just single channels at the expected double sample rate.

Up to 96 kHz (Double Speed), the ADAT outputs can be used in parallel to the AES outputs. In

Quad Speed mode (128 kHz up to 192 kHz), the ADAT outputs are operated synchronously at

Single Speed sample clock, but do not provide any audio data.

The ADAT optical outputs of the ADC Module are fully compatible to all ADAT optical inputs. A

usual TOSLINK cable is sufficient for connection.

ADAT Main

Interface for the first or only device receiving an ADAT signal from the OctaMic. Carries the

channels 1 to 8. When sending a Double Speed signal, this port carries the channels 1 to 4. In

Quad Speed mode ADAT MAIN carries an empty but synchronous ADAT signal.

ADAT AUX

Copy of the data at the MAIN output. When sending a Double Speed signal, this port carries the

channels 5 to 8. In Quad Speed mode ADAT AUX carries an empty but synchronous ADAT

signal.