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Sound eyes the gold medal

Clever graphics and multiple camera angles get the plaudits these days in broadcast sport coverage but, as Kevin Hilton reports, audio is beginning to forge ahead.

There are, in essence, three components to TV sound and televised sports in particular: the clever bits such as surround sound, analysis tools like the Snickometer in cricket and the whooshes used to accompany the video wipes on replay sequences; commentary and presentation; and how these elements are combined and distributed. Surround sound will probably become too well established to be considered a gimmick but in all three areas new applications are being found and technological innovations made.

As befits its status as a leading television sporting event, the FIFA World Cup has often been used to test and popularise emerging audio technologies. This year’s tournament is more about consolidation, with the sound department refining how live sound, both 5.1 and stereo, is captured, mixed and distributed from the venues in South Africa to the International Broadcasting Centre (IBC) in Johannesburg and thence round the world.
The big first for this World Cup is organisational, with the same microphones, Lawo mixing consoles, Genelec monitoring, Dolby encoders and ancillary equipment at all stadiums and in the IBC. Christian Gobbel, senior engineering manager, works with host broadcaster HBS and was audio engineer on the last two World Cups. He is now preparing for his third and drew up arrangements for coverage in South Africa. He explains that the aim is to give “as standardised a product as possible”.

As part of the standardisation programme the majority of microphones will be Schoeps. Among the specialised units is the recently launched SuperCMIT DSP-based shotgun mic, which has been specified to counter a colourful but intrusive facet of South African football: the vuvuzela (pictured). This instrument looks like a brightly coloured hunting horn, is a metre long, made of plastic and makes a lot of noise.

Gobbel says vuvuzelas can produce 114dB of sound and, while they are part of South African football culture, international viewers might find them annoying. SuperCMITs are being fitted to pitch-cameras following the ball, allowing the audio mixer to increase the sound level of “kick action” and go some way to masking the sound.

As at past World Cups there will be no simulcasting of stereo and 5.1. Stereo feeds will be mixed at the grounds on Lawo mc256 digital consoles, with surround sound mixes created at two suites in the IBC, each equipped with a mc266 Mk II. The surround elements will be captured using Schoeps ORTF arrays in a double configuration. The ORTF works on the same principle as Schoeps’s IRT cross, using four cardioid mics to pick up the main spatial elements (L, R, LS, RS).

SoundField DSF-2 mics were used for the main surround feed during the 2006 World Cup in Germany, but in South Africa they will be back ups or alternative sources. “The SoundField system works well in fixed installations,” explains Gobbel, “but a more exciting surround ambience can be produced when there is a phase distance between the capsules. This gives a sense of space and a little bit more directivity.”

Surround sound broadcasting divides into two camps: those that favour arrays of four individual mics and those preferring all-in-one systems. As the pioneering surround mic, the SoundField has been at the forefront of 5.1 broadcasting, with Sky in the UK using it to establish its HD services. The broadcaster continues to use the system to provide audio feeds for Sky 3D.

Whether for HD or 3D, Pieter Schillebeeckx, SoundField’s head of research and development, says there is an increasing demand for surround, although this does depend on the national market. “The UK is very advanced with surround,” he says. “Japan is much the same story but in Germany we’ve noticed a drop in HD delivery, while Belgium is still mono.”

On the subject of surround arrays versus sound mics, Schillebeeckx comments that “in the early days” sound engineers liked to use their favourite mics but with the technology and market maturing the trend has been towards the all-in-one approach. “With day-to-day 5.1 production people are focusing on the practicalities,” he explains, “things like down-mixing, so there’s no need to have separate stereo, and not having to rig every time and having an in-built heating element to drive out moisture. All this is very important.”

SoundField surprised the market recently by introducing the UPM-1 stereo to 5.1 converter. Schillebeeckx says a great deal of stereo material is still involved in HD sports coverage, despite the shift to 5.1. Upmixing systems are also produced by Linear Acoustic – the UPMAX:neo – and DTS, which has the Neural UpMix.

DTS recently introduced the Mono2Stereo, a four mono in, four stereo out unit designed to process mono effects so that they don’t drown out the commentator or presenter and cause intelligibility problems. “It’s another tool to help broadcasters deliver sports coverage,” says Mark Seigle, vice president of business development at DTS.

DTS technology will be used at the World Cup, which Seigle sees as significant for both the company and surround in general. “It’s not feasible for all broadcasters to do 5.1 all the time,” he says, “but we are seeing increasing usage for big events because it adds value.” The latest trend in surround sound distribution is discrete channels embedded in the video signal, rather than a separate, compressed audio carrier. Seigle comments that this
form of working will happen but “not overnight”.

Dolby E encoding is being used during the 2010 World Cup, embedded in the video. This is partly because HBS’s infrastructure is still based on eight embedded channels, whereas
16-channels is necessary for discrete distribution. “There is not a high penetration of 16-channel embedders right now,” explains Gobbel. “But in the future we will work all in discrete.”

Stagetec is approaching the new situation by working with both Dolby E and Serial Digital Interface (SDI) technology. Using SDI allows the video and the audio embedded in it to be synchronised; Stagetec has built an embedding module into its NEXUS console to place finished mixes into the video stream. The XHDI-02 embedder on the NEXUS is able to de-embed the six surround and two stereo channels in a Dolby E stream so they can be dealt with by the console as any other audio feed.

Because Dolby was one of the first companies to address how surround-sound signals can be passed around existing stereo broadcast centres, Dolby E became established and is used widely today. Sky continues to use Dolby E as a carrier but it is moving towards discrete audio embedded in the video signal, using the 16 SDI channels on the mixing console and Axon embedders to encode the sound. Material will be delivered in Dolby E and moved around in discrete format within the broadcast complex, with transmission in Dolby Digital.

Studer has seen a similar move towards discrete embedded audio through SDI, with Dolby E still part of the chain. “It makes sense for all the encoding and decoding to be done at the console,” comments sales director Jamie Dunn. “It reduces the amount of cabling and the possible points of failure.” He adds that integrating coding and routing into the mixing desk saves space and keeps costs down.

At Calrec, business development manager Henry Goodman says facilities are moving towards a single SDI router for both video and audio, with increasing use of embedding. “We’ve found that more customers are using embedded audio signals, often increasing capacity further using Dolby E encoding,” he says. “These are both highly efficient methods of transporting audio data.”

The new generation of HD/3D OB trucks are based on 3G routing infrastructures, which allow SDI capability to be increased as requirements change. 3D uses 5.1 but with a different perspective from 2D TV coverage to compensate for having fewer camera angles, some of which are often lower than usual.

“The new frontier in sports broadcasting is 3D production – we would describe it as video catching up with the audio,” Goodman says. He adds that 3D audio is no different to 5.1 for HD in terms of mixing; the difference comes with the video format: “It is more important than ever for consoles to be able to manipulate 5.1 signals quickly and efficiently, have enough processing for all the channels needed and to have a simple method of controlling all those signals.”

At Dolby, director of broadcast systems Jason Power agrees that the demand for surround is driving an expansion in the ways of carrying 5.1 audio. “We have supported various standardisation efforts to ensure that, where embedded discrete channels are used, Dolby metadata can also be carried so that broadcasters retain

control over the eventual reproduction of their audio in the home,” he says. “Dolby E is particularly being used where broadcasters want an established method of carrying 5.1 audio and metadata locked together, especially where audio is in its final version and they wish to protect against errors being introduced by equipment handling individual channels differently.”

Another level of control that has to be considered in all TV broadcasting is loudness. This is of particular concern to sports broadcasters, who have to cope with different feeds coming in as well as matching the overall output to the commercials and programmes around it. HBS is using the Junger Audio Level Magic system to achieve what Gobbel calls “a consistent loudness for stereo and surround”.

Marc Judor, international marketing and sales manager at Junger Audio, says the company has been working with other leading broadcasters on sports productions, including Pro7 in Germany, Canal+ and ESPN. “Broadcasters beginning to use HD and 5.1 have the possibility to handle loudness as they would stereo,” he comments.

A new product launched by Junger that could find favour with sports broadcasters, although it might annoy some of their peers, is a processor that analyses equalisation styles and recreates them. “If you like the sound of ESPN you can work out the setting and apply it to your own show,” says Judor.

This underlines the part style and presentation play in modern sports broadcasting. Key to that is how the commentators sound. Mayah Communications supplies codec-based equipment to several German broadcasters. RTL has been using systems for its Formula 1 coverage and will be taking Sporty reporter codecs to the World Cup. Public broadcasters ARD and ZDF will be sending the C1161s and some Centauri II that it had in Vancouver for the Winter Olympics to South Africa.

Glensound Electronics produces commentary codecs but also stand-alone units, with the flagship being the digital GDC 6432. “Many broadcasters’ new trucks now feature digital routing and mixing systems,” comments sales and marketing manager Marc Wilson. “Including a digital router within the commentary system extends this flexibility meaning the system’s functionality can adapt to different environments.” HBS is providing 25 GDC 6432s during the World Cup, plus 600 analogue units.

Two newcomers to commentary are Stagetec and Sonifex – but in different ways. Stagetec is using the DELEC oratis system to make commentary part of the wider audio network. Working with the NEXUS platform the configuration is based on a matrix frame housed in an OB truck. This is used as a central audio router and contains plug-in boards. The commentator works at a COM3 terminal linked by a Gigabit Ethernet link to a commentary card in the matrix frame.

The Sonifex CM-CU21 was designed in conjunction with distribution company Sigma Broadcast and has mic and headphone connections for two commentators and guest/pundit, as is the style these days. “The area of sports commentary requires products that are rugged in design and simple to use,” says Sonifex managing director Marcus Brooke. “Having a look at the market, there weren’t that many other products out there so it seemed to be an area that we could expand into, especially with the World Cup this year and the Olympics coming up in 2012.”

While builders struggle on to finish the venues that will be used for the next Games in London, developers and broadcast engineers will probably be beavering away to develop new way of getting the sound of sport across.