Audio processing provides a few benefits that radio or television listeners are sometimes not even aware of. For example, the reduction of dynamic range caused by processing makes listening in noisy environments (particularly the car) much less difficult. In music having a wide dynamic range, soft passages are often lost completely in the presence of background noise. Few listeners listen in a perfectly quiet environment. If the volume is turned up, subsequent louder passages can be uncomfortably loud. In the automobile, dynamic range cannot exceed 20 dB without causing these problems. Competent audio processing can reduce the dynamic range of the program without introducing objectionable side effects.
Further, broadcast program material typically comes from a rapidly changing variety of sources, most of which were produced with no regard for the spectral balances of others. Multiband limiting, when used properly, can automatically make segues between sources much more consistent. Multiband limiting and consistency are vital to the station that wants to develop a characteristic audio signature and strong positive personality, just as feature films are produced to maintain a consistent look. Ultimately, it is all about the listener experience.
Also, the regulatory authorities in most countries have little tolerance for excessive modulation, making peak limiting mandatory for signals destined for the regulated public airwaves.
The OPTIMOD Audio Processors have been designed to address the special problems and needs of broadcasters and netcasters while delivering a quality product that most listeners consider highly pleasing.
Processors must be judged on how they perform with the many different types of program material used in a given format and ultimately should be judged based on their ability to attract and hold a given broad-caster’s target audience. There is no substitute for long-term listening.
The art of audio processing is based on the idea that such benefits can be achieved while giving the listener the illusion that nothing has been changed. Successful audio processing performs the desired electrical modifications while presenting a subjective result that sounds natural and realistic.
More information on this topic, e.g. the differences when it comes to processing for AM, FM and digital broadcasting, can be found in “Maintaining Audio Quality in the Broadcast and Netcast Facility - 2019 Edition”.