TechniSat DIGITRADIO 52 CD, Инструкция по эксплуатации

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7 DAB+ (digital radio) function
7.1 What is DAB+?
DAB+ is a digital format through which crystal clear sound with no noise can be heard.
In contrast to conventional analogue radio stations, DAB+ can be used to broadcast
multiple stations on the same frequency. This is referred to as an ensemble or multiplex.
An ensemble is comprised of the radio station, as well as several service components
or data services which are broadcast individually by the radio stations. For further
information, please visit www.dabplus.de or www.dabplus.ch .
7.1.1 Data compression
By doing so, digital radio takes advantage of the properties of human hearing. The
human ear does not perceive sounds which are found under a specific minimum
volume. Data which is under the so-called audibility threshold can, therefore, be filtered
out. This is possible because, in a digital data stream, the relevant relative volume for
other units is saved for every unit of information. Moreover, in an audio signal, the
quieter parts are superimposed by louder ones at a specific limit value. All the sound
information below the threshold of hearing in a piece of music can be filtered out of
the signal to be broadcast. This leads to a reduction of data in the data stream to be
transmitted, with no perceptible difference in sound for the listener (HE AAC v2 process
as a supplementary codification process for DAB+).