Digital Inputs And Outputs; Madi I/O; Aes/Ebu - RME Audio MADIface XT User Manual

21. Digital Inputs and Outputs

21.1 MADI I/O

The BNC input is built according to AES10-1991. The input impedance is 75 Ohm. It will oper-
ate error-free from about 180 mVpp on.
The optical input and output uses a FDDI (ISO/IEC 9413-3) compatible optical module, accord-
ing to AES10-1991. More information can be found in chapter 30.1, MADI Basics.
MADIface XT includes automatic input selection (Redundancy Mode). In case the current input
signal fails, the unit switches to the other input immediately. This mode, called redundancy op-
eration, offers improved safety against errors on the transmission line. Switching the inputs is
done in less than a sample and - provided the input signal fails abruptly – click free.
The BNC output is built according to AES10-1991. The output's impedance is 75 Ohm. The
output voltage will be 600 mVpp when terminated with 75 Ohm.
In MADI1 output mirror mode output 2 and 3 hold the same signal as MADI port 1. This mode
allows for distributing a signal to three destinations, or redundant operation at the output of the
unit.

21.2 AES/EBU

The XLR AES/EBU input and output is transformer-balanced and ground-free. The incoming
channel status is ignored. Connection is accomplished using balanced cables with XLR plugs.
Input
Thanks to a highly sensitive input stage
SPDIF coaxial can be fed too by using a sim-
ple cable adapter phono/XLR. To achieve
this, pins 2 and 3 of a male XLR plug are
connected individually to the two pins of a
phono plug. The cable shielding is only con-
nected to pin 1 of the XLR - not to the phono
plug.
Output
Using the cable adapter XLR/phono described above, devices with coaxial SPDIF interface can
be connected to the AES output of the MADIface XT as well. Note that most consumer equip-
ment with phono (SPDIF) inputs will only accept signals having a Channel Status 'Consumer'
format. The Consumer status is activated in the Settings dialog. In Consumer mode the output
voltage is reduced as well, as SPDIF calls for a lower voltage than AES/EBU.
The output signal coding of the MADIface XT has been implemented according to AES3-1992
Amendment 4:
• 32 / 44.1 / 48 kHz, 64 / 88.2 / 96 kHz, 176.4 / 192 kHz depending on the current sample rate
• Audio use
• No Copyright, Copy permitted
• Format Professional or Consumer
• Category General, Generation not indicated
• 2-Channel, No Emphasis
• Aux Bits Audio use, 24 Bit
• Origin: MAXT
User's Guide MADIface XT © RME
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