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Additional information
42
Additional information
HiDyn
plus
™ (HDP) noise reduction
This product family is equipped with
HDP
, the Sennheiser noise reduction
system that reduces RF interference. It increases the signal-to-noise ratio
in wireless audio transmission to more than 110 dB.
HDP
is a wideband
compander system which compresses the audio signal in the transmitter
in a 2:1 ratio (related to dB) to lift it above the inherent noise floor of the
RF link. In the receiver the signal is expanded in an identical and opposite
way in a 1:2 ratio to restore the original signal, at the same time reducing
the RF noise to below the noise floor of the receiver.
HDP
has been specially developed for high quality radio microphone
systems.
All receivers of the product family feature a AES3 digital audio output for
digital mixing consoles. In the receiver the audio signal is digitalized as
early as possible so that the noise reduction (compander) can be realized
digitally.
Squelch
Depending on the strength of the received RF signal, the receiver’s audio
output is opened or muted. Via the “
Squelch
” menu, the squelch threshold
can be adjusted in 13 steps from 0 to 30
μ
V.
RF link
Transmitter
Receiver
Inherent
noise
of the RF link
Only transmitters and receivers that are equipped with
HDP
can
work correctly with each other. If non
HDP
equipment was mixed
with
HDP
, the dynamic range would be drastically reduced and the
transmission would sound blunt and flat.
HDP
is permanently
active and cannot be switched off.