It’s All About Good Audio Source and Level Control Brentlinger: Understand the interplay of codecs and hard limiting or clipping Jay Brentlinger is president, CEO and chairman of Circuit Research Labs Inc. He owned Orban for 16 years and now does service, repairs and trade-ins on older Orban legacy products. Robert William Leembruggen is an Optimod technician and former broadcast engineer.
transmission is totally different from digital audio processing for any digital transmission. This is entirely due to all-digital transmissions using some form of perceptual codec to reduce the size of the data being transmitted. If any hard limiting, or even worse, clipping is used, the codec simply cannot handle this and results in high distortion and wasted bits of information.
Radio World: What is your view on the role of the cloud?
Jay Brentlinger: Personally, as a station owner, I would not want RW: Many broadcasters are to depend on the cloud for my working remotely, what are audio. I feel compromised even the implications for processing depending on the internet to management? deliver audio to the transmitter Brentlinger: A station using and feel there must be a backup. Jay Brentlinger and Robert Leembruggen remotely generated audio files My feeling might change with or live source must have proper time, but for now a full local backup audio playout sysautomatic gain control and good final audio processtem is required at the transmitter site when using the ing before the transmitter. Levels can vary from one cloud or audio over IP from the internet. I have proved DJ, announcer or source and this can cause ducking as this to myself many times with my stations. a result to affect the next audio cut. This happens all the time when the producer of the remote audio does not use some sort of AGC or limiting. “Everyone must remember that using
low-bitrate MP3 audio as a source and then to use a codec of any kind makes the sound more distorted and it gets worse every time it happens.�
RW: The health crisis has shown that costly buildings and studios may not be necessary; how does this relate to processing? Brentlinger: All major groups are looking for ways to save money. Brick-and-mortar buildings are a huge cost and allowing DJs and announcers to work from home is a real cost-saving move. But once again good audio source and level control is critical. Everyone must remember that using low-bitrate MP3 audio as a source and then to use a codec of any kind makes the sound more distorted, and it gets worse every time it happens.
RW: What is the most notable development in processing? Brentlinger: Using HD audio processing for streaming and audio over IP.
RW: What about differences in processing for various analog and digital platforms? Brentlinger: Digital processing for analog audio
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TRENDS IN AUDIO PROCESSING FOR RADIO Radio World | October 2020
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