NEXUS – Audio Infrastructure and Networked Control

The NEXUS components from Stage Tec are a family of plug-in cards with which almost all requirements for audio transmission and conversion as well as extremely complex control tasks can be flexibly implemented. Each system can be tailored exactly to the individual requirements of your installation. With NEXUS, Stage Tec uses the industrial standard of 19" subracks, which not only allows you to configure the system in a highly adaptable way, but also guarantees future expandability.

How does a Nexus System Work?

Flexible Configuration in Industry Standard

Each NEXUS system consists of one or more so-called Base Devices. These are based on the industry standard 19" subrack, in which up to 21 plug-in cards can be inserted on one level. The cards can be freely combined to represent exactly the functions you need at a certain position. Subracks are available with 1 - 5 levels (3 - 15 RU in the control cabinet), a 1-RU version with 6 slots is also available.
Two power supplies can be used at each level. These can be connected to one or two phases on the connection side to provide redundancy and maintain function even if one phase of the power supply fails.

Guaranteed Timing and Lowest Latency thanks to TDM Bus

Each Base Device connects all the cards in it via a TDM bus (time-domain multiplexing). This bus provides 256 time slots for the transmission of up to 256 signals. The TDM concept guarantees a fixed, reliable timing with lowest latency. NEXUS ensures that only the signals that are actually in use are switched to the bus at any time, thus conserving resources.

Maximum Operational Reliability through Distributed Intelligence

The central slot in each Base Device is occupied by the XCPU card. This card controls the signal distribution and processing (TDM bus) within the Base Device and has a complex, local logic that can be used to implement even failed control functions within a Base Device or across the entire network. Since the entire configuration of your system is burned into the XCPU cards of all Base Devices (BD's) during setup, each XCPU knows the entire topology. This enables an XCPU not only to automatically control the routing between all connected Base Devices, but also to permanently monitor the entire network.
Ethernet and USB ports are available for connecting control PCs. If individual components fail, the function of the rest of the network is completely retained. This makes it possible, for example, to use individual Base Devices on a mobile basis or only when required. Due to the burned configuration, the boot process is very fast.


Even more Network Security - Redundancy and Flexible Topologies

Several Base Devices can be connected to a network by means of optical waveguides. XFOC cards are used for this purpose, each offering 4 ports for fiber optic cables. The connections between the BD's can be designed completely freely:

  • Point-to-point connections
  • Daisy Chaining
  • Star-shaped connections
  • Meshed networks
NEXUS not only transmits the audio signals via the fibers, but also all control information of the system.
It is possible to make the fiber optic connections redundant in order to achieve even greater security. Not only can the fibers be plugged redundantly, but it is also possible to use several XFOC cards redundantly. This makes it possible to change the cards during operation or to patch fiber optic cables without audio failures.

Hot-Plug, Auto-Discover and Growing Matrix

Each NEXUS CPU detects the Base Devices and their I/O's in the network within a few seconds. The technology is hot-pluggable without restrictions. Each input or output appears automatically in a dynamically growing matrix in which you can flexibly route each input to each output. Distribution to several outputs at different points in the system is also possible. NEXUS takes care of the administration and saves the settings for you at any time. Even after a total power failure, the system automatically returns to the desired operating state within seconds.

Small Distances, Large Distances

The XFOC cards use SFP ports to connect the fiber optic cables, so you can also configure mixed configurations with single-mode and multi-mode fibers, depending on the application. The distance between Base Devices can therefore be many kilometers. All connections are therefore guaranteed to be potential-free. Hum and other interferences are completely excluded.

All Audio Formats - Many Connector Types

In your NEXUS system, you can place audio inputs and outputs completely freely. You are only limited by the capacity of the TDM bus or the fiber optic connections.
Each card type provides you with certain audio formats. Nearly all formats available on the market are supported by NEXUS: from analog to digital to audio-over-IP. Even "specialties" such as Dolby E® or embedded audio in SDI/HDSDI video data streams are supported by NEXUS. Cards are often available with a smaller or larger number of channels and with different connector types. For example, the NEXUS can be designed as a patch panel at the same time, which saves a lot of installation effort. Alternatively, there are cards that can be used in control rooms with inexpensive RJ45 connectors to save space and costs.

The Advantages of a Proprietary System and yet open to Everything

The audio network is usually the heart of every installation. The control data is usually just as important. With the NEXUS from Stage Tec, you can rest assured that there will be no failures due to unexpected malfunctions between components from different manufacturers.
NEXUS uses a proprietary protocol to transfer audio and control data. This guarantees lowest latencies and highest reliability of the system. The latency between digital input and output of two adjacent Base Devices is fixed at only 6 samples.
You don't have to do without anything, because NEXUS offers interfaces with which you can bring almost all common audio formats into the system. This also includes MADI, Dante and AES 67, so you can maintain the security and reliability of NEXUS in your central networks and maintain flexibility in connection to open standards such as IP where you need it..

Powerful Logic and Media Control

NEXUS is not only the system of choice when it comes to audio routing and distribution - NEXUS also includes full media control "under the hood". As with all Stage Tec solutions, the integrated logic offers maximum flexibility and reliability. Once you have created a configuration, it can no longer be easily changed by the user. This guarantees trouble-free operation over the entire service life.

Integration of External Systems

Various cards for NEXUS enable integration with a wide variety of Devices or installation components such as switches, signal transmitters, sensors, DAW's or media controls. For example, the XRI cards provide up to 24 GPIOs. The XCI cards offer up to 4 serial ports, which can be freely configured as RS-232/422/485 or Midi. An Ethernet port is also available. All functions are fully integrated with NEXUS Logic. The cards with serial ports contain memory and processor, e.g. for storing any protocol of Devices to be controlled. Of course, these configurations can be flashed into the card in a fail-safe manner.

Permanent Self-Monitoring and Emergency Solutions

Even in its standard configuration, NEXUS constantly monitors itself and is capable of notifying users on connected PCs about various conditions. With the help of the integrated logic, this monitoring can be expanded even further and, for example, rules can be defined according to which NEXUS calls up certain scenarios if individual signals fail or other undesired conditions occur.
When using NEXUS boards with GPIOs or serial interfaces, monitoring and control can be connected to external components and systems in a variety of ways. The universal XCI control board also makes it possible to integrate NEXUS into an SNMP scenario and monitor any parameter of the entire system. For this purpose, the XCI sends SNMP traps with corresponding information to external monitoring systems in case of an event.

Internal DSP's - High-End Signal Processing on Demand

The XDSP cards offer you a wide range of audio editing functions that you can configure and arrange in your system as required. If required, several DSP cards can also be used in one Base Device to enable the most extensive processing.
The algorithms available on the XDSP card should leave nothing to be desired: Starting with simple delays or summers / mixers via equalizers and crossovers as well as extensive dynamic processing up to complex functions such as an N-1 matrix or upmix/downmix even in ISOSTEM format (license required), everything is possible.
All functions have in common that, as typical for Stage Tec, they are very granularly adjustable. Even the finest tuning of complex sound systems is no problem. All elements can be made accessible to the user or hidden from his access.

Extensive Sync Options and Omni-Present Sample Rate Conversion

When it comes to sync, NEXUS leaves nothing to be desired. The internal synchronisation (system clock) is already available in the basic version and can be set to 44.1 / 48 / 88.2 or 96 kHz as required. Each XCPU card has a word clock connection, via which NEXUS can act as a master or be synced to external sources. If you use digital audio inputs in the system, it is of course possible to define any input as the master. The entire system then follows this input. Of course, Stage Tec also offers all digital I/O cards with sample rate converters, so that you can connect external systems with different clock rates if necessary.
For additional requirements, you can use one or more XSYNC cards. In addition to word clock, these cards also have a connection for video sync, which automatically recognizes the video format and the clock. All formats up to HD with bi- or tri-level sync are supported. Optionally, the connection can also be configured as a master. Since Nexus works very stable with one clock throughout the system, it is possible to distribute an internal or external sync over long distances and to many connected systems.

Unlimited Metering and Monitoring

The PC software that comes with every NEXUS system contains a stand-alone tool for displaying any signal level of the entire network. Desired signals can be freely defined in groups and stored on multiple layers. The software can be operated at different locations, each with its own configuration. At the same time, NEXUS is able to make all signal levels available to external systems for monitoring. In addition to the NEXUS proprietary protocol, which can handle a large number of media control systems from well-known manufacturers, NEXUS also supports the EmBER+ protocol when using an XACI board.

For monitoring applications that require the convenience of a configurable hardware interface, Stage Tec offers the NEXUS Monitor Control, a slim, small touch console optimized to make complex monitoring tasks along with control functions manageable. Of course, a NEXUS system also plays together with any goniometer from other manufacturers.


Mixing Consoles from 4 - 96 Faders and up to 800 Audio Channels

Stage Tec mixing consoles enjoy an excellent reputation in the broadcast and theatre sector. What all of our consoles have in common is that they are seamlessly integrated with NEXUS. Both the surface control and the audio processing are located on plug-in cards for NEXUS subracks. All control functions of the NEXUS system can be operated from the consoles. Functions such as fader start or dynamic automation use the XCI control boards in the NEXUS to connect to external hardware. All logic functions in the NEXUS are also available to the mixing consoles.

Nexus Star Router - Dedicated 4,096 x 4,096 Matrix and Star Point

A special Base Device in the NEXUS system is the Star Router. It always has a height of 6 U and has a huge matrix with 4,096 inputs and 4,096 outputs within the Device instead of a TDM bus. Thus the router is predestined as a star point within an extensive NEXUS system. It is therefore usually equipped with many fiber optic cards. These RFOC cards each have 4 fiber optic ports, prepared for standard SFP modules. This allows a large number of BDs to be connected centrally.
Stage Tec also offers MADI cards for the Star Router for connecting external, high channel systems directly to the matrix. These RMF cards each have 4 MADI ports.
In addition to the pure router functionality, a Star Router can also accommodate the control and processing cards of the larger mixing consoles. Up to two consoles with up to seven RMDQ processing cards each can be accommodated.

Mega Matrix for Special Applications - 8,448 x 8,448 Inputs and Outputs

Stage Tec has developed the NEXUS XRT card for very special applications with the highest routing requirements. This card offers 12 fiber optic SFP ports for connecting Base Devices. This uses special, high channel connections that allow the full capacity of 8,448 x 8,448 inputs and outputs on the matrix to be utilized.


NEXUS is an extremely flexible system with an enormous number of possible uses. Starting with individual Basic Devices, which can be used purely for format conversion and/or synchronization, to smaller systems, which can be used in schools, hospitals, sports facilities, shopping malls, etc. with maximum operational reliability and longevity. From the most complex systems for broadcasters or large airports, everything is possible. Please do not hesitate to contact us!