Vendor Content.

All Routes Lead To HOME

Talk to any audio engineer in the broadcast or live segment and they will tell you that separating the control surface (some call it the front end) from the I/O stageboxes and routing/patching section (the back end) as well as the DSP processor makes their lives so much easier, especially if such a setup evolves around an intuitive management system.

Let us agree to call the exploded setups described above “mixing systems”, as the console proper is, in fact, a highly sophisticated controller that sends commands to a DSP processor like Lawo’s A__UHD Core. As such, the console does not process anything. Even models equipped with local inputs and outputs convert incoming, or outgoing, signals to/from IP, turning them into so-called “streams” that are processed by the DSP engine, somewhere on the IP network.

This triple separation offers a number of indisputable benefits: one DSP processor can be shared among several mc² consoles and software GUIs for different mixes (FOH, monitors, recording, several concurrent broadcast productions) and doesn’t even need to sit next to the console or at the venue; the stageboxes used to ingest and output audio signals can be placed close to the sources and destinations wherever they may be on planet Earth; sound engineers can bring their own project files, secure in the knowledge that these will not overwrite the stream routings someone else has prepared on-site; and a lot of “administrative” work can be prepared in the mxGUI software on the way to the gig.

Sound supervisors in charge of immersive or multichannel audio mixes for world championships and global athletics jamborees usually have such a busy schedule that they literally use every second on the train or plane to get the better part of their configuration work done before they enter the IBC (international broadcast center) or production hub.

Busses To Busses, Funk To Funkier

As explained in this Themed Content Collection, most mixing systems offer busses (AUX, Solo, etc.), groups (VCAs, channels) and sums for maximum mixing flexibility. One thing to look out for is how far you can go with this structure. Some sound supervisors indeed like to work mainly with VCA groups and need the ability to route any given VCA channel, which is already a collection of input channels, to one or several other VCAs. This quickly makes things rather complex—assuming that the mixing system supports this at all. To tell the various VCA channels apart, the system should furthermore offer a map function for swift identification and navigation.

And just so you know: digital consoles like the mc² series have no analog amplifiers whose level can be controlled via voltage. The term “VCA” (short for Voltage-Controlled Amplifier, a name inherited from analog consoles) is only used to provide a concise, yet clear description of the purpose of these groups.

The more (sub)grouping and summing options there are, the more important a function like “Reveal” becomes. At the press of a button, it enables automatic input sorting of VCAs, subgroups and AUXes that causes the console to assign all channels of the selected bus or group to the console strips, starting at a pre-defined or user-selectable (Reveal in Place) position. This gives instant discretionary access to all grouped channels, irrespective of which bank or layer they belong to.

This is important for tweaks that should only affect one or a few channels of a much larger group. When you are done, you press the REVEAL button again, and the console reverts to its previous channel layout.

Another strategy that often leads to more complexity—mainly when live performances are involved—relies on using available AUX busses, of which there should be at least 128 in total, for the monitor mix or mixes. Now imagine mixing a popular Saturday evening show both for the broadcast feed and for the musicians who perform live on set. Even the most talented sound supervisor only has two hands and a finite number of faders. Juggling between on-air and monitoring may be a bit much or downright impossible.

Given the processing power of the Lawo mixing system in use, adding a second console for the monitor mix may be a pity or simply not practical. Enter the ability to create monitor mixes on a tablet, based on the assigned AUX channels. For each musician individually, if so desired, complete with AUX Level and Panning Controls, using the labels, colors and AUX assignments of the mc² console, and delivered via a highly responsive HTML5-based user interface.

One Step Beyond

Back to our mixing system. With the artistic license offered by a powerful mixing concept comes complexity. If not stowed away under the hood, such complexity may lead to the impossibility to see the forest for the trees in time-critical situations.

Separating the I/O stageboxes from the console and the DSP processor offers the advantage that issues with one gateway only partially affect the overall system’s functionality. The worst that can happen is that some input sources are no longer audible and/or that some outputs do not feed the required destinations. Depending on which sources and destinations are affected, this may very well turn into a full-blown nightmare, especially during live shows or sporting events watched by millions.

Unless the analog or digital sources and destinations are connected to splitter boxes feeding two separate stageboxes for a redundant setup at source or destination—if one box fails, the other is ready to take over—some manual repatching may be involved to get the show back on the road.

Luckily, broadcast-grade stageboxes like Lawo’s A__stage and A__line series are famous for their reliability, because they were built to function 24/7. Inadvertently sectioning one Ethernet cable used for the IP network connection is not really a problem: the stageboxes’ built-in redundancy system ensures that the other Ethernet port, connected to a redundant switch, will automatically be used while someone replaces the faulty cable.

Unlike A__line gateway devices with a small I/O count, which are perfect for areas where a little over a handful of signals need to be accommodated, A__stage devices come equipped with between 48 and 80 inputs and outputs. Plus, a redundant MADI port for input and output devices that do not support RAVENNA or SMPTE ST210.

Using three or even more gateways quickly provides operators with a dazzling number of routing options. Connecting a laptop to each of them and making the required settings is hardly ever an option, as this is both time-consuming and error-prone. The same procedure would have to be used again to tweak the connectors’ input and output parameters. In today’s hectic production environments, this is no longer an option.

HOME & Dry

Enter Lawo’s IP management platform called HOME. Launched two years ago, and substantially expanded ever since to include both audio and video tools, it is a comprehensive and intuitive software-based management solution for everything to do with stream routing, securely admitting new devices to the network, communicating with both HOME-native and NMOS-compatible devices, and… tweaking the parameters of the various devices connected to the IP network.

Of course, stream routing in the IP domain has always been possible, but it used to take a lot of blood, sweat and tears at the configuration stage, which either involved connecting to each device individually or preparing everything in a broadcast control system like VSM.

All current Lawo hardware and software as well as selected Merging Technologies and DirectOut devices are either HOME natives or so-called first-class citizens, which is functionally the same. Routings and extensive parameter tweaks can conveniently be set on a computer monitor or an mc² console screen. A clear GUI makes routing inputs to outputs—either individually or in groups—intuitive and fast. Configuring parameters for remote audio or video gateways from the monitor or screen is just as easy, as is routing signals from one gateway to another.

The best part is that each mc² console contains a HOME instance, so that HOME doesn’t need to be run on a server cluster for smaller installations. In a high-performance broadcast setting, there are obviously a lot more devices and software apps that need to communicate with one another, either locally or remotely. For scenarios involving more than 32 devices, a HOME server cluster is advisable.

Bottom Line

Even a large infrastructure with countless IP-networked devices doesn’t have to be complex to the point that only the most committed engineers manage to make sense of all the ins, outs, groups, busses, sums and routes.

The fact that a lot of configuration work can be prepared ahead of an assignment, using Lawo’s mxGUI software, which, by the way, also runs on Apple silicon computers equipped with M-series chips is a major timesaver.

And did we already mention that despite all their assistive and intuitive features appreciated by thousands of leading sound engineers, Lawo consoles are first and foremost famous for their superior sound?