07.04.17

Loudspeakers join the network

Loudspeaker closeup

With audio networking spanning the entire system – from inputs to endpoints - Justin O’Conner explores what that means for the selection, deployment and management of loudspeakers.

It’s a surprise to no one that in the world of audio technology there is much debate over networking. The discussion includes consideration of media transport, control languages, switches and the merging of AV with IT. 

All of this debate used to belong primarily to the selection of DSP systems, mixers, and control systems. As the benefits of moving the network further to the end points have become more apparent, microphones and amplifiers are now included in the discussion. Now many loudspeaker systems are network devices. While this is a natural extension of innovation, the ramifications of integrated networking in loudspeaker systems means that the age-old approach of specifying a system from the loudspeaker up isn’t as ubiquitous as it once was.

There is no rule about how to best design an audio system. There are many variables that are up for consideration, and just as many approaches to take. A favoured one has been to start with the acoustic coverage needed for the room, which in turn leads to a loudspeaker choice, then the remaining devices are specified in an upstream path. 

Even in a networked system, this approach can largely continue the way it always has if the loudspeakers themselves aren’t networked. But more and more loudspeaker manufacturers are equipping the loudspeakers or loudspeaker systems with networking technology. 

There are many benefits including easier setup and tuning, more intuitive operation, faster troubleshooting, and greatly simplified reconfiguration and control. The challenge for system designers now is that there are certainly cases where the protocol to be used is dictated by other factors such as network infrastructure or control system needs. If this in incongruous with the preferred loudspeaker choice, then there is an added complication to designing the system.

One loudspeaker manufacturer that has turned its attention toward networking is d&b audiotechnik. As Wolfgang Schulz, product manager Installation, told me: “The ability to integrate an audio system, including the loudspeakers, amplifiers and software tools, into a network infrastructure is very beneficial. Today's venues typically need to serve multiple uses, and so does the technology built into them.” 

System connectivity is a major focus for d&b. It supports the Open Control Architecture (OCA), which has recently been ratified as AES70 and provides a method for control and media to be merged on the same network.  The d&b catalogue is such that designers can match up the loudspeaker they want with d&b amplification and the DS10 Audio Network Bridge using Dante to have a complete networked loudspeaker system. This provides not only the benefit of getting the signal to where it needs to go, but in allowing control of networked devices.

Meyer Sound also provides networked loudspeakers as well as networked systems. The CAL Column Array Loudspeaker products have network ports directly on the loudspeakers themselves, making them endpoints within the infrastructure. Additionally, with the D-Mitri family of networked processors, any of the loudspeaker products can become part of a networked audio system. 

“It comes down to the things you want to know about your loudspeaker system; is a driver in over-excursion, is there clipping, is there an impedance or current problem? We’ve provided much of this feedback through our RMS (Remote Management System) for years, but the more of that we can provide on an Ethernet network, the better for everyone,” said Michael Creason, product manager for Systems Applications and Training at Meyer Sound.

The benefits of networking loudspeakers can be enjoyed by nearly every stake holder in an audio or AV system. Installation requires far less expensive audio cabling and is rather accomplished through Ethernet cables. Bringing the audio system up and tuning it goes much more quickly. Regular use and quick re-configuration for multi-use spaces can be accomplished through various system features like pre-sets and programmable operation modes. 

“The ability to integrate an audio system, including the loudspeakers, amplifiers and software tools, into a network infrastructure is very beneficial.”

Trouble shooting and preventative maintenance can not only be accomplished without the use of scaffolding, but the possibility exists that it can be done from another building or another part of the world. Additionally, Ethernet based audio systems provide elegant advantages for control through the audio devices themselves or through IP integration with third party control systems. Integration with non-AV systems such as security and alarm solutions can also be done more effectively and more transparently. 

Indeed, the benefits are far reaching, but they come with other complex decisions. As there are various competing network protocols, each one comes with various benefits and trade-offs. 

Audio Video Bridging / Time Sensitive Networking (AVB/TSN) and Audinate’s Dante are likely the two that come to mind first for most in the industry. Additional protocols such as Ravenna from Lawo and the interoperability protocol AES 67 are also part of the discussion. They all require certain elements with regards to network infrastructure and they all have benefits and considerations. 

AVB/TSN is an Institute of Electrical and Electronics Engineers (IEEE) ratified standard which is of great importance to IT stakeholders, but requires specific switch hardware. It is worth noting that the number of switches available for AVB/TSN operation has been and will continue increasing. 

Dante enjoys a large number of licensees and fewer switch restrictions, but is completely beholden to one manufacturer, makes no provision for video as AVB/TSN does, and is not recognised by the IEEE. These factors can have great influence on the choice of networking technology for a given system, a choice that may or may not involve the consideration of which loudspeaker system is compatible with each network.

For example, Meyer Sound has settled on AVB/TSN for the Galaxy, D-Mitri and CAL. According to John Monitto, director of Technical Solutions, “The audio quality of the network as well as the streaming reliability are of great importance to us. Our customers look to us for our quality and performance. We are optimistic about the innovation we see in audio networking.” 

Creason and Monitto both agree that the traffic handling and bandwidth reservation of AVB/TSN are critical to the stability of the network.

Dante is the network of choice for d&b at this stage. Schulz identified Dante as the protocol that “meets the demands and requirements of an Ethernet audio network for our customers.” It is worth noting that d&b has joined the AVnu alliance and is closely monitoring AVB/TSN developments, but for the time being they see Dante as the most widely available solution.

Add to the mix other proprietary offerings such as Ravenna, and QLan from QSC Audio, as well as the rise of AES 67 for interoperability, and the choices can become complex quickly. It’s then a surprise to no one that there is so much continuing discussion in the industry over networking. 

Venues and AV service providers are now becoming experts in IT and in-house IT managers are now finding themselves responsible for AV systems. This has been going on for years, but as the network reaches further and now stretches all the way to the endpoint transducers, the consequences of a network decision can have significant impact on the devices included in the system. The factors that impact the protocol choice and the factors that impact the loudspeaker choice may not be the same.
It can be noted that many loudspeaker manufacturers have seen the benefits of providing networked loudspeaker and loudspeaker systems. In addition to d&B audiotechnik and Meyer Sound, L-Acoustics, Harman brands JBL Professional, BSS and Crown, QSC, Pan Acoustics, Kling and Freitag, Renkus Heinz, and several others have loudspeakers and loudspeaker systems that support some form of networking. This is a vector of innovation that is a part of the world of loudspeakers and we will continue to see an increase in offerings. 

There is another consideration that is worth mentioning. Not all customers will accept networked technology. There is a lingering concern that an Ethernet based solution, even though cabling is more elegant and convenient, is not as inherently reliable as a system based on analogue cabling. Whether or not that is true there is a general feeling that if something happens in an analogue system, one can just plug things in or patch around the problem with analogue cables. This may or may not be the case with an Ethernet system, particularly depending on the location of the problem. There is also an infrastructure challenge for providers of systems for hire that makes traditional analogue cabling more useful. There is never a concern for compatibility between the elements of a system while trying to shuffle the available stock. 

“An audio provider never wants to be in a position where they are making excuses to the customer.”

As Meyer’s Creason puts it, “An audio provider never wants to be in a position where they are making excuses to the customer.” With regard to live reinforcement systems, permanent installations, or systems for hire, staying away from Ethernet audio systems may provide that safeguard.

Manufacturers are paying a lot of attention to network technologies. The entire industry has been stretching and growing for years and achieving significant innovation through the careful and creative implementation of network technologies. 

While this has been happening for years, it has also seen a surge recently as the worlds of IT and AV continue to overlap, blend, and in some cases oppose each other. The extension of the network to the endpoints has added to this surge. Loudspeaker manufacturers are essentially working with a core set of technologies that are rather mature. Differentiation and innovation are not as readily available and apparent at the transducer level. But certainly, the rapidly growing world of networking opens up an entirely new palette for loudspeaker offerings.

The concerns and complexities of networking that the AV industry is grappling with will continue for some unknown time into the future. As loudspeakers have come to include this technology they have, in turn, inherited these considerations. It is a time of some unrest in the industry, but it will not remain this way. It will get better and the possibility of all of this just becoming Ethernet audio, rather than a set of protocols to choose, from is more likely than not.