NAB Replay - Routing switchers

Digital switching of video and audio signals is now standard in many broadcast facilities, with many products providing multi-rate SD/HD capability. Hybrid systems capable of routing combinations of analog and digital signals within the same matrix are still the solution for integrated applications. AES and embedded audio solutions are now becoming more accepted, especially with the advent of quiet AES routers. Routers range from 4×1 to 1024×1024 or larger, but it is often the control capability that is the deciding factor when choosing a new routing system.


The CP-1000A is one of the programmable panels offered by Quartz.

Typically an increase in the physical size of the router produces an increase in the complexity of control. This complexity is based on the need to control a wide variety of features including the control of multiple matrix frames, multiple signal levels, virtual matrices as subsets of a physical matrix, and internal features such as swapping the left and right audio channels. A graphical user interface can provide Ethernet control with remote configuration, status monitoring and control capability.

Leitch offers a control system that combines control of large routing systems, such as their Integrator series, with many of their smaller legacy frames. The new Panacea small routing solution can also be incorporated into an existing control system to allow expansion without the need to replace an entire control system.

Miranda was awarded a Pick Hit for its Densité SCP-1121 SDI control probe.

Programmable panels are also becoming more economical to produce, allowing a 16×1 panel to be programmed for use as two 8×1s, four 4×1s or even eight 2×1s. The same panel could also operate as an X-Y panel for 8×8 control, 10×6 control, 12×4 control or some other combination. Quartz offers a variety of programmable panels, including the CP-1000A, with display buttons that change their label and color depending on the current function. Sources can be assembled for fast selection groups of sources and destinations.

PESA offers a selection of control panels that work with matrices from 8×8 on up. Thomson Grass Valley, Leitch, Ross and NVision are among others that offer a variety of different control panels to suit single destination, multibus control as well as full or restricted X-Y control.

NVision offers a unique approach with their NV900 control system. It resides in a control panel, thus removing the need for a separate control computer. Other systems use an online PC or internal or external server to provide the brains to control the router.

Digital audio (AES) routing systems are available from many manufacturers such as Thomson Grass Valley, PESA, Utah Scientific and NVision. Matrices may also offer control of signal parameters such as left only, right only or the ability to swap channels. Control of these parameters may involve a simple “swap channels: button, although selecting “VTR-X” to choose a swapped path is also an option.

Large AES audio routers such as the Thomson Grass Valley Apex and the NVision NV7256 router use TDM to make interconnection of individual matrix frames simple and efficient. The ability to switch AES signals without audio disruptions is often important. AES signals need to be processed and synchronized before the switch is made to make quiet switching possible. Chyron (Pro-Bel) offers hybrid solutions with the Halo and Procion series, which offer both analog and digital I/O, enabling mixed input formats to be routed to digital or analog outputs simultaneously. The PESA Cheetah series includes the 448X Flexi-frame providing HD to SDI output conversion cards and 10-bit D/A output options to feed existing analog systems. Utah Scientific's Utah-400 offers eight port groups for analog I/O into a digital environment.


Nvision’s NV5128 master control routing switcher can accommodate combinations of analog and digital in an 8RU frame.

One flexible option is the NVision NV5128, the MC upgrade to which was awarded a 2003 Pick Hit. This 8RU frame can accommodate combinations of analog and digital, and video and audio up to 128×128 in increments of 16. Signals are converted to digital for internal routing. The matrix frame also accommodates routing and SD master control modules.

Tie lines can allow sources to be routed automatically between matrices through external conversion products. This offers the ability to combine analog and digital hardware while integrating the old with the new. Tie lines also allow smaller distributed matrices to be utilized while keeping a single control system.

Systems like the PESA Cheetah series of digital video routing switchers are able to route signals from 3Mb/s to 1.5Gb/s. The Thomson Grass Valley Trinix and 7500 WB routers and NVision routers also offer routing solutions that cover the full spectrum of signals. A universal digital matrix offers the ability to incorporate HD signals in the future. The Leitch Integrator Gold also provides switching of any signal between 30Mb/s to 1.5Gb/s in matrices anywhere from 8×8 to 128×128.

An abundance of small routing switchers are available from manufacturers like Network Electronics, Ross Video, Sigma, Ensemble Designs, Quartz, Knox, Sierra Video Systems and Miranda. These companies offer solutions that cater to the low-cost, small- to mid-range video and audio routing needs. Sierra Video Systems offers its Sequoia range of small routers while Network Electronics' VikinX range of small routers provides both Ethernet control and SNMP reporting, often only found in large systems. Sigma Electronics offers small analog or digital, V and A from 16×1 to 32×2 and 4×4 to 16×16. Ensemble Designs also offers an 8×1 and 8×8 range of video utility switches in their Avenue range of products.

Thus, there is an abundance of routing choices available today to suit a variety of needs, signals and control options.

Mike Betts is the senior partner of Broadcast Training Partners.

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