TechniSat DigitRadio 250 User Manual

Page 17

Data compression

Digital Radio exploits aspects of human hearing

for data compression. The human ear does not

detect sounds that are below a certain minimum

volume. Data below the absolute threshold

of hearing can therefore be filtered out. This

is possible because the digital datastream

also saves the relative volume of each unit

of information to other units.

At a specific threshold, the quieter parts of a

sound signal are blocked out by the louder parts.

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 reduces the

size of the datastream to be broadcast without

a perceptible difference in sound for the listener

(MUSICAM procedure).