SA station addresses phone-in audio levels

South African commercial radio station OFM is tackling the problem of varying audio level and quality during its phone-in shows by using sound levelling technology, writes Kevin Hilton.
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South African commercial radio station OFM is tackling the problem of varying audio level and quality during its phone-in shows by using sound levelling technology, writes Kevin Hilton. The broadcaster has installed a Jünger Audio D06 Level Magic processor at its studios in Bloemfontein for audience participation programmes. OFM is a "lifestyle" station, mixing adult contemporary music, news, weather and that staple of radio anywhere in the world, the phone-in. Technical manager Jan Van Der Walt (pictured) says the poor quality on telephone connections used for broadcast was a major challenge, so he began looking for ways to improve the sound. "As almost all of our content is live, the poor quality on telephone conversations we were broadcasting became quite a problem," Van Der Walt comments. "It 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. 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." A stand-alone two-channel D06 version of Level Magic has been installed in OFM's main studio and is connected to AES inputs and outputs, as well as an Axia live wire system. All programme material is run through the D06 before going to the station processor and studio-transmitter link.


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