TechniSat DigitRadio 50 - Manual (Page 9)

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After changing only the small DAB or the FM logo is displayed right next to the time.
DAB mode
What is DAB?
DAB is a new digital format, through which you can hear crystal clear sound in CD
quality. DAB Broadcast a high-speed data stream in the radio channel. In difference to
conventional analog radio DAB transmits multiple channels on the same transmitter.
This is called ensemble or multiplexes. An ensemble consists of the radio station as
well as several service components or data services, which are sent individually by the
radio stations. Learn e.g. under www.digitalradio.de or www.digitalradio.ch.
Data compression
Digital radio uses the of advantages of human hearing. The human ear does not
perceive sounds that are below a certain minimum level. Data which are under the
so-called threshold in quiet can be filtered out. This is possible because in a digital
data stream for each information unit, the corresponding relative volume is also saved
for other units. In addition in a sound signal, the quieter portions are overlapped by
the louder for a given threshold. All the sound information in a piece of music that are
below the so-called hearing threshold can be filtered out of the signal to be transmit-
ted. This leads to a reduction of the transmitted data stream, without any noticeable
difference in sound to the listener ( MUSICAM ) process.
Audio Stream
Audio streams are continuous data flows, MPEG 1 Audio Layer 2 frames contain and
thus represent acoustic information in digital radio. Thus, familiar radio programs can
be transferred and listen at the receiver side. For Digital radio the MUSICAM format
is used, which provides two MPEG compliant PADs. This is referred to as PAD data
services. Digital Radio brings you not only radio wit for additional data. The excellent