+ System

system-neuThe NEXUS system use digital Time Division Multiplex (TDM) technology. Every Base Device features an audio bus with 256 time slots and can therefore process 256 different signals at the same time. The time slots can be dynamically assigned in order to increase the number of possible simultaneous routing processes in large networked systems.
The I/O boards convert input signals to the internal data format and assign the resultant data to time slots, or read and convert them for output, respectively. Multiple boards can read and use the same signal at the same time.
The XFOC fibre-optic interface boards bundle the 256 signals to transfer them to other Base Devices over optical lines.
The XCPU Base Device controller board controls and monitors all functions (including TDM handling and synchronisation) and all boards. The controller board also handles the control information on the audio network and the routing system. It communicates to the user-interface computer and — via optical lines — to the other Base Devices on the network.

+ Simple Network Management Protocol (SNMP)

news3Many companies use the Simple Network Management Protocol (SNMP) as a centralized management solution for monitoring routers, computers, servers, etc. NEXUS networks can also be monitored using SNMP. The XCI communication-interface card acts as an interface between the NEXUS and SNMP. The card provides general information (e.g. the number of Base Devices) as well as all error messages occurring on the NEXUS network to the SNMP Manager. You can also use NEXUS logic functions to generate SNMP messages: Any event that can be detected using logic functions can be reported through SNMP.

+ Mixing Console Systems

NEXUS can also be used as the input and output matrix for Stage Tec mixing-console systems (AURUS, CRESCENDO, AURATUS, ON AIR 24). In such setups, the consoles use the NEXUS I/O resources. However, the integration of mixing console and audio network goes much further than this and deep into the architecture of both systems. For example, the NEXUS can be operated from the console configuration computer. The console also provides dedicated keys for direct access to frequently used NEXUS parameters such as gain, phase inversion and filters for microphone inputs, activation of the sample-rate converter for digital inputs or injection of the internal test-tone generator.

Multiple mixing-console systems integrated on an audio network can share resources. This topology is not only cost-effective, since each console does not require costly dedicated converters, but also allows for multiple utilization of all signal sources. The vocalist microphone signal can be routed to the monitor mixer, the FOH mixer, the OB truck and, in an unprocessed form, to a MADI output feeding a recording workstation.
The AURUS and CRESCENDO consoles are designed to provide a high channel count, thus using the NEXUS STAR audio router provides an enormous routing capacity for complex applications. Since the NEXUS STAR uses NEXUS Base Devices as distributed I/O interfaces, all NEXUS audio components are also accessible to the AURUS and CRESCENDO.

+ Analogue-Audio

The XAD+, and XDA+ 8-channel analogue line-I/O boards offer an exceptional dynamic range of 133 dB (A) and 131 dB (A), respectively. Furthermore, the XMIC+ 32-bit microphone-input board achieves an impressive 158 dB (A). The XMIC+ inputs can also be used as line inputs without switching. This means that microphone clipping, or even microphone-gain adjustment, is now a thing of the past! The XMIC+ can be used either in the classical way with a single digital output, or as a splitter with up to four independent outputs per microphone input.
In just 4 HP, the HXAD and HXDA boards make available eight analogue stereo inputs and outputs, respectively, via D-sub or RJ45 ports! Both converters are designed for maximum analogue levels of up to 15 dBu and are suitable mainly for permanent installations.

+ Digital-Audio

A wide range of interface boards is available for various digital audio formats. The boards convert audio and ancillary data to the NEXUS 24-bit TDM format and are also be equipped with sample-rate converters for connecting asynchronous devices. The interface boards have been officially certified for Dolby E® signal transmission by Dolby Labs.

+ SDI-Audio

Serial Digital Interconnect (SDI) is an internationally agreed standard for transmitting digital video with embedded audio and ancillary data. The shared, synchronised transmission path for video and audio over a single line offers a number of benefits, for example, when transferring via satellite links or routing over SDI video crossbars.

The XHDI 02 slide-in board provides an SDI interface and supports SD, HD and HD-3 G video formats. The board receives, generates and processes synchronous and asynchronous audio signals transported in a digital serial video stream. The following specifications have been implemented: SMPTE 259M (SD), SMPTE 292M (HD), and SMPTE 424M/425M (3 G).
The XHDI 02 embeds and de-embeds metadata streams used mainly during transport and processing of multichannel audio signals.
Use in combination with Stage Tec’s Dolby E® enabled components allows for de-embedding and decoding Dolby E® signals from an SDI stream, processing them in the NEXUS, and finally re-embedding them into the SDI stream. This is also supported for SDI signals clocked asynchronously. The XHDI 02 is also capable of compensating for the latency intrinsic to Dolby E® decoding and encoding using a video delay of 0-15 frames (SD) or 0-8 frames (HD/3 G).

Dolby and the double-D symbol are registered trademarks of Dolby Laboratories.

+ Audio Transmission

Dolby E® signals are routed transparently and can also be processed dis­creet­ly on the NEXUS audio network. I/O interfaces to the NEXUS include AES/EBU, MADI and SDI formats.
Stage Tec offers two Dolby E® boards that allow for discreet processing of Dolby E® audio. The XDED decoder board decodes a Dolby E® stream and ex­tracts the separate channels and forwards them to the NEXUS system as dis­crete audio signals. Asynchronous input signals can also be decoded. The XDEE encoder board encodes up to eight discrete audio signals from the NEXUS system in compliance with the Dolby E® encoding specifications. Both boards use original Dolby Labs OEM modules.

Dolby® Laboratories has exam-ined and certified the transparency of the NEXUS hardware. Stage Tec is an official Dolby E® partner.

Dolby and the double-D symbol are registered trademarks of Dolby Laboratories.

+ Logic Control

logic-control-neuNEXUS Logic Control is a programmable logic software unit for switching functions defined according to each user’s individual needs. Logic Control enables various NEXUS parameters to be queried including, for example, crosspoint statuses, fader-start relays, I/O levels, internal error statuses, etc. When used in conjunction with an AURUS console, Logic Control can also perform certain mixing functions such as fader remote start contacts and machine-control keys.
Logic Control is capable of controlling a variety of outputs and events including, for example, red-light control, crosspoint and line-level monitoring, mute keys, program switches, fader starts, auto backup-link switchover and intercom systems.

In this NEXUS workshop you can read an introduction to the extensive possibilities offered by NEXUS Logic Control and its latest enhancements

+ Audio Processing

XDSP audio-processor boards are used when audio signals not only need to be routed, but also processed. The processing channels incorporated on a processor board can be applied anywhere on the routing system regardless of the board’s physical location.
The standard version of the board provides channels featuring parametric equalizers, delay and gain. Options include parametric filters, faders, mixers, delay and dynamics units, and even a fully-fledged gain/delay matrix.
The XFAD board was designed to implement a feature often desired in the control room: a smooth crossfade between lines being routed. The crossfade can be controlled using external signals.

+ Relay-control Signals

Relay-control Signals

Apart from routing audio, NEXUS systems also provide a number of control and switch­ing functions. The XRI relay-interface board is available for interpreting, gen­er­ating, and distributing relay-control signals.
Relay functions can be programmed for specific applications:

  • Supported ap­pli­ca­tions include routing signalling and remote-start on the NEXUS network,
  • control of selected NEXUS functions using switches,
  • and control of ex­ter­nal loads or equipment.

+ Control Interface

The universal intelligent NEXUS communication interface (XCI) extends the functionality of a NEXUS audio network with control features. The user can control external devices remotely and query control protocols using the XCI board. Applications include connectivity to hardware or software operating panels for controlling specific NEXUS functions, or the connection of remote-controlled peripherals such as power amplifiers, CD players or audio recorders. On request, other protocols and/or device-control functions can be implemented for other devices in addition to the pre-programmed standard protocols.

+ Data Transmission

The NEXUS, as a virtual, freely routable data cable, is perfectly suitable for routing external control data. Using the XTI data-transmission card, serial data signals are transmitted transparently over the network. The board supports a number of interface specifications including RS 232, RS 422 (RS 485), MIDI, DMX (RS 422/485), Timecode, LTC, and Dolby Metadata (RS 232 or RS 422).
The data streams are routed by the NEXUS control software in the same manner as audio signals and are transmitted transparently.

+ Data Retention

The working memory on the XCPU controller board in each Base Device is battery-buffered. In the event of a power failure the last state is stored. When power is reapplied, it takes only seconds to restore all settings to the most recent state.
System and routing settings all fall within the scope of data-retention. Whenever the NEXUS system is powered up, it resumes its most recent status within a few seconds. This all happens autonomously in the NEXUS system — no external control computer is required.