ClearOne XAP400 - Manual (Page 39)

33 System Configuration ~ Inputs and Outputs
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The Speech Leveler is a compander that is optimized for speech audio. It
quickly equalizes the difference in speech levels in the room without bringing up noise.
If you use AGC with the Speech Leveler, set the AGC Response Time to >2 seconds.
AGC adjusts softer and louder input audio to a consistent level that you select
(the target level). The target level range is from -30 to 20dB in 1dB steps. The
default target level is 0dB.
Set the Target Level first, then apply the amount of maximum gain that you
want the AGC to apply to the signal. Maximum gain range is 0 to 18dB in 1dB
steps. The default value is 18dB. AGC occurs after the gain and filter settings in
the audio signal path.
The Active Gain meter reflects the overall gain at any given moment. Click
the white box next to the meter to enable it.
The Response Time adjustment determines the total AGC engage/disengage
response time. The Threshold determines the decibel level at which you want the
AGC to engage. Setting the threshold toward the higher end of the scale (near 0)
reduces background noise to a greater degree. The Response Time is measured in
milliseconds. Target Level and Threshold are both RMS.
P Pwr (Phantom Power)
Phantom Power toggles the phantom power on and off. Phantom power is an
auxiliary power source to power certain types of microphones. The XAP 400’s
phantom power voltage is 24VDC. Default is On.
AEC
AEC opens the Acoustic Echo Canceller window. To enable the acoustic echo
canceller, click Enabled, then select the reference. Any one of the eight outputs, four
expansion bus references, four virtual references, or Speaker output can be selected.
PA Adapt and AEC Reference
If you select an expansion bus reference, the Define PA Adapt/AEC Expansion
Bus Ref window opens so you can identify which expansion bus output you want to
use as the AEC’s reference. You can also open this window from the toolbar.
Figure 3.27. AGC/Speech Leveler window
All meters in G-Ware are
peak meters. The target
level and threshold
controls in the AGC/SL window
reflect RMS values.
Figure 3.29. AEC window
Figure 3.28. Define PA/AEC
window and toolbar button