AVT MAGIC THipPro Lite, Configuration Manual

Page: 96 / 158

▪
VOLUME CONTROL DEFAULT VALUE: The level of
the audio signal coming from the caller can be
adjusted manually in the PC software if AGC is
disabled. Define the default amplification here. It
is set each time a call is disconnected so, the next
call starts with the default value.
▪
ECHO CANCELLER: The echo canceller eliminates
echo coming back from the caller in POTS, and
VoIP mode. It is not used for HD-Voice calls. There
is a dedicated echo canceller for each telephone
channel.
It is recommended to adjust the audio levels so
that the TX level displayed on the main panel of
the PC software is between -18 dBFS and
-12 dBFS.
▪ ACTIVE: Enables the echo cancellers. Especially
analogue telephones cause strong echoes.
▪
LINE BASIS DELAY: The echo canceller can detect
and eliminate echoes with a delay of up to 120 ms.
Each telephone network has an individual minimum
round-trip time for echo signals. This timespan can
be ignored by the echo canceller. The defined line
basis delay moves the 120 ms range of the echo
canceller.
A value of e.g. 60 ms enables the hybrid to
eliminate echoes which occur within 60 ms to
180 ms.
▪ Recommended values:
▪
POTS: 0 ms
▪ POTS with PBX: 40 ms
▪ VoIP: 60 ms
▪
LINE LEVEL OFFSET ATTENUATION (SEND): Define
how much the level of the audio signal being sent
over the telephone channel to the caller is
attenuated. Decrease the value if the returned echo
signal is too strong to be eliminated by the echo
canceller.
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Signal Processing (3)