The Decoder Card for Dolby-E and Dolby-D

The XDED board series is designed as Dolby-E and Dolby-D input board for the NEXUS system. It supports all features provided in the Dolby specifications and supplements them with useful options such as auxiliary sync generation to allow limited operation even if video sync is missing. The connections are both optical as Toslink and electrical with 110 Ohm balanced and 75 Ohm unbalanced. The handling of metadata is flexible and, thanks to the functions of the NEXUS network, far beyond the usual.
The XDED card is a decoder for Dolby E and Dolby D signals. The card is available as single (S) or dual version (D), which indicates the number of Dolby signals that can be processed simultaneously. It provides up to 8 individual decoded channels from the Dolby data stream of the NEXUS matrix. In parallel, the card can receive another AES stereo signal, which is usually transmitted unencrypted as a comment or control signal. In order to really support all possibilities within the NEXUS system, not only the decoded individual signals are transmitted to the matrix but also the coded PCM original signals for each Dolby stream. These can be routed transparently and independently of the individual signals on the NEXUS network. This is also possible in the opposite direction, so that the card can receive the signal to be decoded from any AES input in the system. Audio signals from XHDI video deembedder boards can also be used. There is also a direct cable bridge for these cards, which establishes a particularly low-latency connection by bypassing the network. In addition to all these I/O options, the XDED card calculates a simple stereo downmix of the Dolby 5.1 signal.

The Dolby decoder module is connected downstream of the sampling rate converter so that the external signals do not have to be synchronized to the NEXUS system clock. There is an adjustable delay for all audio signals. The metadata contained in the data stream is unpacked and made available. They can be routed via the NEXUS network to and output from any XTI or XDEM boards. They can also be forwarded to an adjacent XHDI video interface via a direct cable connection and embedded in an SDI data stream. The metadata channel also has an adjustable delay.

In addition, the NEXUS software allows the display and editing of metadata and the front panel of the board offers various connections: Two Toslink sockets are used to connect optical signals in S/PDIF format. In the single version of the card only input 1 is used. Two or, in the dual version, four PCM AES/EBU signals can be fed in via a 15-pin D-Sub connector. Of course, these inputs are balanced and galvanically isolated. They have an adjustable gain and a delay. 110 Ohm and 75 Ohm lines are supported. There is a separate video input for synchronous signals in formats such as composite, component and HDTV. Bi- and tri-level sync are supported. In order to guarantee video frame-accurate synchronization of Dolby-E, this input should be correctly connected due to the system, but the XDED card can generate an auxiliary signal, with which limited operation is possible even in the absence of video sync. In addition, the board is capable of generating an audio sync from the video clock to which the entire NEXUS network can be synchronized.

Direct Connection to XHDI Cards for Audio Transfer

Dolby signals that are bound to an HDI signal can be transmitted from the XHDI board to the XDED board via a direct connection in the form of a ribbon cable and decoded there.

Sample Rate Converter as Standard

The signals applied to the inputs can be conformed to the NEXUS system clock by means of sample rate converters fitted as standard.

Optionally Equipped with 1 or 2 Dolby Modules

A single XDED board can be equipped with up to two Dolby decoder modules to process two separate Doby data streams.

Simultaneous Decoding of 2 Doly-E/D Encoded Signals Including Metadata

When equipped with two Dolby modules, two separate Dolby data streams can be transferred from the XDED card to the NEXUS system.

Decoding of the Metadata and Routes of these System-Wide to any XTI Interface Cards

The metadata contained in the data stream can be read out and displayed in the NEXUS operating program. In addition, the metadata can be transmitted system-wide and output via an XTI board or the XDEM extension.

Adjustable Delay for Delay Compensation Compared to the Video

To avoid runtime differences caused by video processing or audio compression

Connection of up to 2 PCM Dolby E Audio Signals to 15-Pin Sub-D Connector

In addition to the Dolby input, two linear PCM signals can be fed in via a 15-pin Sub-D interface on the front panel.

Equipped with 2 Toslink Inputs

The two Toslink interfaces of the XDED card are used to connect two separate Dolby data streams.

Provides Dolby E/D 5.1 Signal and Stereo Downmix Simultaneously in NEXUS

In addition to the decoded 5.1 signal, the XDED board also provides a stereo downmix.

Inputs can also be used for Non-Dolby Coded Signals

Compressed formats such as DTS or MPEG are recognized and displayed by the operating software. They can be transparently transmitted to external decoders through the NEXUS network.

Combined BNC Connector for Bi-/Tri-Level-Sync and SDI/HD-SDI-Sync

The BNC connector can be used for both analog and digital sync signals.

XDEM Expansion Card with Serial Metadata Port Optionally Available

The XDEM module is not a stand-alone plug-in board but an extension for the NEXUS boards XDED, XDEE, XHDI and XCPU. It provides two additional RS232- or RS422-compliant 9-pin D-Sub interfaces, which can be used to access the metadata ports of these boards. It is a simple, direct solution to pass metadata to or read metadata from these boards when none of the other higher-level solutions available with the NEXUS board are used.

Technical Specifications :


XDED_01 1 x 4TE
Toslink 2x S/PDIF Input
D-Sub 15 Socked female 1x AES/EBU Input
BNC 1x Wordclock Input

Technical Specifications

Data Formats

Dolby D/E as specified for Dolby modules(CAT No. 552)
Linear PCM inputs compliant with AES3, IEC958
Container format data stream compliant with SMPTE 337M
Audio inputs 16, 20, 24 bits (Dolby E); 16, 32 bits (Dolby D)
Audio data to the NEXUS 24 bit
Sample rates 44,1 kHz, 48 kHz, max. 50 kHz
Latency 1 frame (40 ms @ 25 fps). Other paths feature adjustable delay functions.
Interface extension XDEM optional expansion card for the output of metadata

Inputs AES/EBU

Format Comply with AES3, IEC958, S/PDIF
Input ports balanced, galvanically isolated
Impedance 110/75 ohm (adjustable using a jumper)
Input voltage 0.25…7 VPP on RL = 110/75 ohm)
Max. cable length 100 m (for lines with appropriate impedance and termination)

Inputs Toslink

Wavelength 650 nm
Optical power –27…–14,5 dBm (APF 970/1000 μm)
Cable length 0,2…10 m (APF 970/1000 μm)

Sync Input

Supported video formats NTSC 525i, 59,94/60; NTSC 525p, 59,94/60;PAL 625i, 50; PAL 625p, 50;HD 720p, 50…60; HD 1035i, 59,94/60; HD 1080i, 50…60; HD 1080p, 23,98…60
Frame rates 23,975…60 fps
Impedance 110 kohm/75 ohm (adjustable using a jumper)
Input voltage 0,5…2 VPP an RL = 75 Ohm

Operation Conditions

Temperature range 0° C to +50° C
Max humidity max. 90 %, non-condensing

Storage Conditions

Temperature range –35° C to +70° C
Max humidity max. 90 %, non-condensing

Power Supply

Voltage +4,75…5,25 V
Currrent typ. 540 mA, max. 750 mA (one Dolby module fitted)
typ. 830 mA, max. 1200 mA (two Dolby modules)

Mechanical Data

Weight 0.32 kg (equipped with two modules)
Downloads :

NEXUS / NEXUS Star Technical Specifications




XDED Technical Specifications