Commercial audio… Trickle-down tech
In this instalment Jason Allen looks at the latest PA technology, which will eventually become the norm for everyday installations.
And even at the lower-priced end of the market, innovations can come from unlikely sources.
Big changes in audio technology are often driven by the largest customers with appropriate budgets. In live sound these are the big touring companies such as Clair Bros in the United States, major events such as the Olympics, and prestigious venues at the level of the Sydney Opera House.
If there’s a performance advantage, a technical problem to be solved or an economy to be found in a new technology, these organisations have the means to be early adopters.
Take the case of digital mixing desks. In the first few years of the millennium, Yamaha and DiGiCo were behind a small but influential market for live digital mixers, with models that cost more than $100,000. Today, $3,000 or $4,000 puts a smaller version of the same technology in your local pub.
It took years for professional users to bring about the change, but as familiarity with the technology spread from the elite to the professionals and down to the amateurs, a huge market opened up for manufacturers.
Now it’s the turn of the mass market to change things from the other direction. Three big manufacturers – PreSonus, Behringer and Mackie – have released digital mixers that are effectively stage boxes with digital signal processing (DSP), no hardware control and wireless operation from tablets or computers.
These products give you all the functionality of a digital mixer without being tied to a central location. They also enable multiple users to mix at the same time, giving musicians control of their monitor feeds via a tablet or phone.
PreSonus got in first with the StudioLive RM rack-mount series. Two models – the 16 in, 8 out, RM16AI and the 32 in, 16 out, RM32AI – are scalable and connectable. They run on Mac, Windows and iOS devices.
Soon after, Behringer announced the X Air series, with three models offering wireless mixing: the XR12, XR16 and XR18. With four, eight and 16 mic preamps on each model respectively, they are controllable from iOS, Android, Mac, Windows and Linux – and even come with built-in WiFi.
Mackie is the latest brand to enter this space with the DL32R, a mixer with 32 mic preamps and 14 outputs that can be controlled from up to 10 iOS devices at once.
The devices from all three brands offer various digital connectivity options, effects and the ability to multi-track record directly to hard disc from the device. It seems they are all banking on lower-end users being happy to sacrifice physical faders for flexibility.
The biggest change in the day-to-day business of wiring up PA systems in the past couple of years has come from Sydney company Audinate with its Dante audio over internet protocol technology (AoIP).
Although AoIP has existed since the 1990s, it has really taken off since Dante made it simpler, cheaper and easier. All three of the wireless mixers just described have Dante options, and more than 150 manufacturers include Dante in their products.
Dante has become so pervasive that Audio Technica have just released a boundary microphone for boardrooms that doesn’t even have an analogue output – just an RJ45 with Dante. So why has Dante taken off where others have not?
Audio over IP is slowly replacing analogue cabling because it’s cheaper. A single Category 5 cable worth five cents a metre can carry 512 channels of 48kHz, 16-bit audio. You can use a venue or building’s existing IT network equipment or, if that’s not available, buy switches and Cat 5 cabling cheaply. Because the IT industry is so large, network equipment is a commodity product, making it accessible on any budget.
Dante has been adopted for installation and live production because it’s the first AoIP technology that doesn’t require an IT background to use. It is extremely simple to set up using Dante Controller software, has latency so low as to be irrelevant and, most important, can run on networks with other IP traffic with no issues and no special configuration.
It’s that last issue that hampered widespread adoption of its predecessors.
The live production sector initially welcomed Dante with open arms. One of the first big manufacturers to embrace the format was Yamaha, with a Dante option card for its popular digital mixers. Yamaha soon began building Dante interfaces directly into its mixers and remote I/O boxes. Yamaha liked Dante so much, it bought a stake in Audinate.
Pretty much all major mixing desk and I/O manufacturers soon added the 64 in, 64 out, Dante Brooklyn chip to their products. When Audinate released the even cheaper four in, four out, Ultimo chipset in 2013, a vast range of affordable products became possible, right down to domestic level AV receivers.
In addition to simple and cheap connectivity, Dante has some nifty software tricks up its sleeve. Dante Virtual Soundcard is a driver for Windows and Mac, which effectively turns your computer’s Ethernet port into a Dante device. Running as ASIO, WDM or Core Audio, the driver enables compatible applications to route audio to and from the Dante network, with up to 64 in and out possible if your CPU is up to it.
Recording live performances is a breeze – simply patch all of your mixer’s direct outs into mono channels on your recording software. More precisely, run the audio from a presenter’s PowerPoint presentation over the network into the venue’s DSP.
Not a company to rest on its laurels, Audinate has announced Dante Via, a software product that turns any available audio channel on your computer into a Dante channel. This includes audio channels from applications like Skype or iTunes, and any inputs and outputs on connected audio interfaces, be they internal, USB, Firewire or Thunderbolt.
All available channels appear in the patching screen of Dante Controller and are easily connectable to each other. You can now build an entire Dante network by connecting computers (and without buying actual Dante hardware).
However, Audinate didn’t have this market entirely to itself. A range of competing technologies from other manufacturers is aimed at different markets, and emerging open Standards are freely implementable by anyone.
Audio Video Bridging (AVB) is an open Standard ratified by the IEEE that has altered the Standard of Ethernet itself in order to accommodate high-bandwidth, low-latency audio and video over IP networks. It has some powerful backers, including the car industry, which seek to use it in AV systems.
AVB is being held back by Ethernet switch manufacturers such as Cisco and HP, which haven’t yet enabled compatibility in their products.
The Audio Engineering Society is also putting forward its own AoIP Standard – AES67, which was ratified in 2013. In addition to offering a Standard for transport and format, enabling any manufacturer to build an AES67 interface, it also covers interoperability. Gear fitted with Dante can route audio to gear fitted with AVB or any other AES67 compatible format.
The industry seems poised to adopt AES67 across the board, with all main AoIP manufacturers already announcing compatibility – or at least a timetable for compliance.
With all of this digital connectivity available, it’s little wonder that the technology is spreading throughout the entire signal chain. Although adoption of AoIP started on large channel-count items, such as mixers and I/O boxes, it has now migrated all the way to one or two-channel devices, such as microphones.
Manufacturers of digital wireless microphones in particular have been enthusiastic adopters of Dante. Market leaders Shure and Sennheiser first introduced the technology at the top end of their ranges, then slowly filtered it down their line-up.
Digital wireless systems – such as Shure’s widely adopted ULX-D – not only have the advantage of connectivity to the rest of the system via Ethernet but also the smarts to find and allocate transmission channels in an increasingly crowded and hostile radio frequency (RF) environment.
On January 1, 2015, Australia’s changeover from analogue to digital TV will be complete and the vacated spectrum, along with a sizeable chunk that until now has been available for wireless mic use, will be taken over by telco mobile services. Most wireless systems more than three years old will become unusable due to interference – and illegal.
The remaining spectrum that we operate in is smaller than previously. We’re also using more channels in the same space, due to the popularity of wireless microphones and the increased use of in-ear monitors.
To make matters even more fun, the frequency ranges safe for wireless use differ around the country, depending on where local digital television is transmitting.
An intelligent system such as ULX-D scans the local RF environment, selects the cleanest frequencies and automatically applies them across the transmitters and receivers. The efficiency of Shure’s digital transmission system means that up to 17 transmitters can co-exist on one 6MHz chunk of bandwidth, and you can increase that to 47 if you activate its high-density mode.
If you want to go more in-depth, software such as Shure’s Wireless Workbench can be used for manually scanning, monitoring and configuring complex radio systems.
It’s always worth setting up something like Workbench whenever you are using wireless. You never know who is running other radio mics in your vicinity, or what weird piece of gear someone might be operating from their garage. Once you have scanned and identified safe operating channels, most digital radio mic transmitters can simply be held near the receiver and have their settings transmitted to them. This is a huge improvement over the days of setting everything up manually with tiny buttons in the mic.
Sennheiser’s range-topping Digital 9000 system takes frequency management onto a huge touch screen on the front of its EM9046 receiver. Like other digital management systems, it can allocate multiple channels to multiple microphones without the user having to calculate frequency relationships by hand to avoid intermodulation.
To optimise bandwidth use, the Digital 9000 employs uncompressed digital audio transmission, compared with various compression techniques on other wireless systems. At well in excess of $40,000 for a simple Digital 9000 system, user interfaces such as the giant thin film transistor screen are still the preserve of large production companies and broadcasters, but it’s only a matter of time before this feature starts appearing on less-expensive systems.
Neumann (owned by the Sennheiser Group) has been famous for high-end studio and broadcast mics for decades. Mostly seen in recording studios or in live sound for classical applications, they are usually part of an all-analogue signal chain.
But even Neumann’s purist customers are embracing digital technology. The company’s Solution-D wired microphone system sends digital audio directly from the mic and enables control of filters and polar patterns via a computer. Neumann’s DMI-8, eight-channel digital mic interface can receive the output and send it to multiple AoIP formats, including Dante competitor Ravenna.
The AES42 Standard for digital mic output and control is used by Neumann and numerous other manufacturers to provide a common feature set and interoperability between different models.
An AES42 mic can change its sample rate, word clock, compression settings and more on demand, as well as offering remote monitoring and management. Again, this technology is currently available only to those with large budgets, but good things are sure to come to those of us who wait.