Input Aec Block (C Models Only) - Extron electronics DMP 128 Plus User Manual

Set Defaults Button — Resets all filter parameters of all filters in the filter list to their
4
default values.
To reset a single filter to default parameters, right-click the filter number on the left side
of the
Figure 50.
OK Button — Confirms changes made to the contained parameters and closes the
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Filter
Cancel Button — Reverts any changes made to the contained parameters back to
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their states when the current instance of the
the dialog box.
Filters Help Button — Opens the
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file. This help file topic discusses each filter type in greater detail.

Input AEC Block (C Models Only)

About AEC
Echo occurs when audio from a talker in the far end is received and amplified into the near
end listener's room, with that sound then being picked up by microphones in the near end
acoustic space and sent back to the far end. The amount of signal sent back to the far end
talker can be substantial, and with the added transmission delay, the result is an echo effect
that can seriously compromise communication in a teleconference or videoconference.
The Extron Acoustic Echo Cancellation (AEC) processor removes the potential echo
signal at the near end mic channel by comparing it to the received signal from the far end,
designated as the "reference," and then creating an adaptive filter to cancel the potential
echo before it is sent back to the far end.
Successful operation of the AEC processing block is mainly a function of proper gain
structure and selection of an AEC reference. This section provides an overview of those two
elements.
Proper gain structure involves the relationship between the signal at the selected reference
and the signal at the mic input, within the context of proper levels for the reference and mic
inputs independently. The mic input gain setting will naturally be optimized for the voice level
of the talker in that room. Therefore, the amount of signal from the far end picked up by the
mic is dependent on how much far end signal is being amplified in the near end room and
the distance from the mic to the speakers.
dialog box, and select
Filter
Set Single Filter Parameters to Default
dialog box.
(see figure 50 below).
Set to Default
dialog box was opened and closes
Filter
topic in the DSP Configurator Help
About Filters
DMP 128 Plus • DSP Configurator Software 28