Remote Audio 8, Nashville.

An inside view into MTV Networks recently refurbished mobile audio truck. First published* by Mix Magazine, April 2007
By Claire Hall

Left to Right: Marc Repp, Stan 'Quack' Dacus, and Greg Lankford.

MTV Networks managers and engineers knew that this was going to be a tough challenge. With the 22nd Annual Stellar Awards set for Saturday, January 13, at the historic Grand Ole Opry House in Nashville, the mobile audio truck scheduled to record the broadcast was being tag-team driven back to its Nashville base only a few weeks before engineers were to complete a technical refurbishment of the truck in time for this prestigious awards show. And to add to the pressure, this was the week before the Holidays when most were looking forward to enjoying time with their families, not preparing to rip up floors to lay new cables and to install a new audio console.   

MTVN’s Mobile Unit 8 audio truck has been in successful service for a considerable number of years. From its base in Nashville, and as a frequent traveler to production locations throughout the United States, this 48-foot audio truck has been at the audio heart of numerous television music shows and broadcasts spanning the last 10 years. Over 150 major award shows and thousands of broadcast concerts over the years, a testament to the quality of the production and technical crews involved, and the level to which this mobile truck has risen. At the center, the Neve Capricorn console, the first all-digital large format audio console and a remarkable piece of technology for its time, was now beginning to show the stress of constant travel. Ten years on the road is a lot to expect from any console. In addition, broadcast technology is increasingly moving to HD, with 96 KHz audio sample rates becoming the requirement for a music CD mix-down or a DVD production. 

Therefore a decision was made 12 months earlier to replace the console, upgrade video monitors to HD and move towards 96 KHz sample rate recording using two separate hard drive recording systems, each capable of 96 tracks of recording at 96 KHz. And because Mobile Unit 8 and crew were the preferred choice for this annual award spectacular, any remaining day in the completion countdown was a day not to be wasted. 

Greg Lankford, EIC for Mobile Unit 8, describes the project as being a unique experience:

“We used as much MTVN staff as possible in order to meet the engineering deadline of January 8th. Stan Quack Dacus, staff audio mixer at MTVN, was even tasked to cut and haul cables – everyone got involved. The challenge was not just to finish the refurbishment and upgrade on time, but also to be on location on January 10th for the rig and technical rehearsals. So there was very little margin for error. Cable continuity and testing had to be complete with all systems installed and running without problem. There were to be no last-minute issues other than the predictable fine tuning at the location.”

The planning stage took three months, with both Lankford and Marc Repp, project manager and also staff audio mixer at MTVN, hammering out the details of what they wanted to change, what materials and people they needed, and what schedule could be realistically agreed. Using as much of the existing infrastructure as the new specification would allow not only saved money, it also saved time.

“We decided to use the existing analog patch fields,” says Repp. “In the initial construction of the truck in 1996 we had configured the patch fields to terminate in DL connectors which then mated to DLs feeding to and from the Neve console and other outboard equipment. It was then a simple matter, wherever possible, to build new DLs to feed the new console, a 56 fader Lawo mc266.”

“Our decision to bring in the Lawo was taken after a long evaluation period involving all the principal console manufacturers. Although unknown in the US until relatively recently, but a major brand throughout Europe for many years, the Lawo digital console proved to be a familiar operating surface, similar to the Capricorn in many ways, but with the added bonus of being able to give us lots of DSP paths at 96 KHz, and a massive 512 DSP paths at 48 KHz.  The console also provides us with additional operational features, and lots more redundancy. Comments from other broadcasters here in the US and in Europe had first pointed us in their direction, and with extensive operational trials and rigorous pre-amp tests our decision was made.”

Repp goes on to say that their major requirement from the very beginning was to have as many inputs as they could possibly get and to be able to monitor a minimum of 64 tracks – not only at 48 KHz, but also at 96 KHz. “Shows are getting bigger not smaller,” he says.

“This truck is now only one of a very few that can handle such a large amount of inputs and track sends. I can now change the whole sound stage smoothly and at speed, so for multiple band shows this is ideal. And what’s more, the sound of this board is outstanding – everyone agrees.”

The cases for the new stage boxes and their I-O panels were ordered in advance, as was thousands of feet of new cable, all to be pre-built and terminated before the new console arrived. Designs also for how the whole system could be connected together had to be agreed and priced. With the space saved by replacing the old console with the new, it was also possible to physically change things around. The existing pair of ProTools HDTM systems for example could now be moved to the back of the truck. Each pre-wired for 96 tracks, but hardwired to AES connections to the console I-O interface via separate AES cards. This one-to-one input connectivity was preferred to a MADI-style of distribution, minimizing connections to additional conversion racks, providing a further level of redundancy. There is also a third AES card to handle another 64 tracks if and when required. Although this effectively locks the ProTools HDTM  to the console system core, Lankford explains that there is a cost saving to be had by adopting this method. Mobile Unit 8 records straight to FireWire operating one of the ProTools HDTM  systems on-line using a MAC protocol, and using an 800 FireWire buss. The other system is a back-up using a PC protocol with a 400 FireWire buss – each across multiple Quantegy Black Diamond drives.

“With the new console we have a lot more redundancy than we ever had before,” says Lankford. “We decided to continue this into other systems, especially in the black-burst and wordclock synchronization system, as well as throughout the fiber connected I-Os.”

“We are extremely conscious to make sure everything is held in sync in order to prevent any chance of signal glitching due to synchronization issues, and to protect not only against equipment failure, but also to minimize connector-cabling problems due to on-the-road mechanical vibration or through connector oxidation”.

Mobile Unit 8 uses two Apogee Big Ben master digital clocks each fitted with Apogee’s X-Video card. This optional card has a connection for a video reference input and three video reference outputs, in addition to the existing six wordclock outputs genlocked to the incoming video. The video reference inputs to each of the Big Ben units are fed from a separate video isolation DA whose inputs receive the external reference from the video production truck, or from any other video reference source. A video reference output from each of the two X-Video cards then connects to a changeover switch whose output is connected to a pair of video DAs to distribute genlocked black-burst to other equipment in the truck.

In addition to this arrangement, a wordclock output from each of the two master clock units connects into the A and B transformer balanced inputs of a Rosendahl Nanoclock wordclock server, which provides up to 12 wordclock outputs. These outputs are then used to distribute wordclock throughout the truck.

To check for the presence of the external reference source into the truck, Lankford has used an additional output from each of the two video isolation DAs at the front of the master clock units to feed an audible alarm and signaling rack. This a custom-made unit which checks for the absence of the video reference signal into the two master digital clocks. If one of the input references is lost, an audible alarm will sound informing the crew that one of the master clock units is without reference. If this happens then the changeover switch feeding the reference black-burst into the pair of video black-burst DAs is manually switched to receive the output of the second master clock unit.

“I know we could have done this many different ways,” says Lankford, “but the method we finally chose is simple and cost-effective - it works for us. And just in case, we also have the ability to patch things around if necessary as all the inputs and outputs of the sync and video referencing system are brought to a video patch panel in the rack just above the master digital clocks and wordclock server unit.”

A small 16-channel rack mounted digital console has been used in the past for effect microphones and the occasional voice-overs. However, Repp explains that this is being used less frequently as they also installed a second smaller Lawo control surface which provides added redundancy. He says that in the future this additional surface will be used as a separate stand-alone mixer.  

“We all felt that putting as much redundancy as possible into the truck would be the best investment we could make,” says Repp. “Not only did we achieve this within budget, but we also have a great sounding truck. Everyone is delighted.”

To date, MTVN Mobile Unit 8 has successfully completed a total of three shows at 96 KHz, progressively increasing the number of tracks used at 96 KHz from 48 tracks for the first show to 56 tracks for the second, and finally 64 tracks for the third. However, more shows are planned. Country Music Television is currently recording a series called Crossroads pairing up well known artists in country music - artists such as Bruce Hornsby and Ricky Skaggs. There are also shows in the Cross Country series planned, and many more music award shows.

The 22nd Annual Stellar Awards first aired on WGN Cable January 27th 2007 co-hosted by Kirk Franklin, Tye Tribbett and Mary Mary. Further airings continue. For more information go to the Stellar Awards website at: www.thestellarawards.com

All enquiries concerning MTVN Mobile Unit 8 should be directed to Bill McFall at (615) 335-8391. Email: bill.mcfall@mtvnnashville.com

The MTVN Remote Audio 8 Truck

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