Components

• MADI-format I/O board
• Extended number of channels compared to the MADI standard format (up to 64 channels)
  
• Four identical ports per board
• Automatic channel-number recognition (1 to 64)
• Synchronisation to the input-signal wordclock
• Featuring either optical or electrical BNC ports
• Officially certified by Dolby® for Dolby E signal transmission
  Dolby and the double D are registered trademarks of Dolby Laboratories.

MADI-Format I/O Board

The Router MADI Format board connects to the serial MADI interface (Multichannel Audio Digital Interface) and includes four 64-channel MADI ports. The board allows for a simultaneous transmission of 256 inputs and 256 outputs with low space requirements.

This NEXUS STAR interface board is provided, for example, for connecting multichannel audio recorders or external mixing consoles.

In addition to the operating modes required by the MADI standard (AES 10-1991, AES 10id-1995), the RMF board provides the following extra features:

• The number of transmitted I/O channels is extended to 64. When receiving data, the number of channels is recognized automatically. The number of output-channels is user-configurable.
• The input signal can serve as sync source in the NEXUS audio network.

Inputs and Outputs

The duplex board is supplied with either BNC ports (75 ohm, coaxial) or optical ports (SC, 1300 nm, 62.5 / 125-µm).
Contrary to the MADI standard the electrical BNC interface features differential, galvanically separated input and output ports. An unbalanced version is also available on request.

Input Data

The RMF board receives all audio data on the input channels. User data is transparently forwarded on the NEXUS system, for example, to AES/EBU or other MADI-interface boards.

The RMF board recognizes the following information and ancillary data in the data stream::

• Number of input channels
• Sample rate
• Channel-status bytes 0 to 3 containing the following information: format, emphasis, lock, sampling frequency, channel mode, aux use, audio-sample word length, and multi-channel descriptor
• Channel parameters (on/off, A/B, validity)

Output Data

The RMF board sends all audio channels in MADI standard (a maximum of 64 channels can be achieved). In transparent mode, all ancillary information is adopted from the signal source (MADI, AES/EBU).

In addition, the board provides extensive options for status and ancillary data that can be set by the RCX:

• The status of each channel can be set. (128 data frames are provided for this function.)
• User and validity information can be either fixed to static levels or derived from the input signal (MADI, AES/EBU) in transparent mode.
• The number of the channels to be transferred can be set to either 56 or 64. In addition, the ON / OFF and A / B information can also be configured per channel.

Note: The settings described depend on the software and may therefore not be available (or even reasonable) on every system.

Metering

The RMF board features two signal processors that determine the levels of all received and transferred channels in an accumulating manner. These DSPs are monitored by watchdogs.

Indication and Error Detection

The state of the Base-Device connections is constantly monitored for each port. In addition, the Base-Device connection to the RCX routing matrix is checked.