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Selecting a Reference Signal for AEC
To apply AEC, provide a far end reference signal. For best results, use the signal that also feeds your local reinforcement sys
tem.
P300:
Go to Schematic and click any AEC block. Choose the reference source, and the reference source changes for all AEC
blocks.
MXA910, MXA920, MXA710:
Route a far-end signal to the AEC Reference In channel.
IntelliMix Room:
Go to Schematic
and click an AEC block. Choose the reference source. Each block can use a different refer
ence source, so set the reference for each AEC block.
Designer's Optimize
workflow automatically routes an AEC reference source, but it's a good idea to check that Designer choos
es the reference source you want to use.
AEC Settings
Reference Meter
Use the reference meter to visually verify the reference signal is present. The reference signal should not be clipping.
ERLE
Echo return loss enhancement (ERLE) displays the
dB
level of signal reduction (the amount of echo being removed). If the
reference source is connected properly, the ERLE meter activity generally corresponds to the reference meter.
Reference
Indicates which channel is serving as the far end reference signal.
Non-Linear Processing
The primary component of the acoustic echo canceller is an adaptive filter. Non-linear processing supplements the adaptive
filter to remove any residual echo caused by acoustic irregularities or changes in the environment. Use the lowest possible
setting that is effective in your room.
Low:
Use in rooms with controlled acoustics and minimal echoes. This setting provides the most natural sound for full du
plex.
Medium:
Use in typical rooms as a starting point. If you hear echo artifacts, try using the high setting.
High:
Use to provide the strongest echo reduction in rooms with bad acoustics, or in situations where the echo path fre
quently changes.
Noise Reduction
Noise reduction significantly reduces the amount of background noise in your signal caused by projectors, HVAC systems, or
other environmental sources. It is a dynamic processor, which calculates the noise floor in the room and removes noise
throughout the entire spectrum with maximum transparency.
Settings
The noise reduction setting (low, medium, or high) represents the amount of reduction in
dB
. Use the lowest possible setting
that effectively lowers noise in the room.
Automatic Gain Control (AGC)
Automatic gain control automatically adjusts channel levels to ensure consistent volume for all talkers, in all scenarios. For qui
eter voices, it increases gain; for louder voices, it attenuates the signal.
