With phone-in programmes playing an important part of its programming, South African commercial radio station, OFM, faced a serious challenge in ensuring consistency of audio quality and levels.

‘One of our biggest technical challenges was the poor quality of the telephone conversations we were broadcasting,’ admits OFM Technical Manager, Jan van der Walt. ‘Almost all of our content is live, and this was particularly noticeable when callers were using cell phones and were in areas of poor signal. But we also had problems with some fixed line calls where the position of the caller’s phone could influence the level of the incoming audio. The result was that the energy level of the telephone audio was often lower than the standard audio we were broadcasting. This meant that the phone calls sound much softer, which in turn made it difficult for audiences to hear, especially if they were driving and were trying to hear the radio above the ambient noise around them.’

OFM’s mix of adult contemporary music, news, weather, traffic and other information is delivered 24/7 to South Africa’s Free State, most of the Northwest province, parts of the Northern Cape and the Sothern parts of Gauteng.‘Many of the people who listen to us often drive huge distance, in excess of 800km,’ says van der Walt. ‘Obviously it can become very annoying if you can’t hear the telephone contributions.’

Attending South Africa’s Media Tech show, he found Jünger Audio through its South Africa distributor, Tru-Fi Electronics and was impressed by the stand-alone two-channel D06 Level Magic processor. This automated control unit uses an adaptive level control algorithm to adjust the level from any source at any time, with no pumping, breathing or distortion. It works by simultaneously combining an AGC, a Transient Processor for fast changes and a ‘look ahead’ peak limiter for continuous unattended control of any programme material, regardless of its original source.

‘What I wanted was an audio processor that would just fix the levels that were wrong, rather than changing the entire program,’ he says. ‘I am always scared of “over processing” because I believe that the challenge of great audio is to let it sound as close as possible to the natural origin of the sound. What I liked about the unit was its ability to work only with level and not process the audio. It seemed to me that this might be the right option for us because I could use it to just correct the phone levels.’

Initially Tru-Fi installed a two-channel D06 for evaluation, even though OFM thought it might need a larger four-channel unit. ‘My original plan was to buy the four-channel unit and put the phone line through one channel, the news sound contributions via PC through a second channel and use the remaining two channels for playout of the entire programme,’ says van der Walt. ‘However, because the D06 only has two channels we decided to wire it to the AES in and outputs and put the final programme through it. The results were way beyond anything I expected. In fact they were so great that I refused to allow Tru-Fi to take the unit out – I just bought the demo! We use an Axia live wire system, so it doesn’t matter where the unit is physically installed, but in my case it lives in my main control room and all of our main programme output goes through the D06 before it is fed to the processor and the STL.’

The D06 has solved FM’s level problems with telephone calls, aloowing listeners to hear all of the programme content, regardless of where they are located or where phone-in participants are calling from.

‘The best thing about the D06 unit is how easy it is to use, but I also like the fact that it is transparent and does nothing to the audio except fix the level,’ van der Walt adds. ‘We are really happy with it and it is working very well for us. There couldn’t be a better name for this product than Level Magic, because the Jünger Audio D06 really does do magic with the levels that used to be a big problem all over our shows.’

More: www.trufi.co.za
More: www.ofm.co.za
More: www.junger-audio.com