User`s manual

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4.4.2: 1-Channel Adaptive Filter
Application:
The 1-Channel Adaptive filter is used to automatically cancel predictable and convolutional
noises from the input audio. Predictable noises include tones, hum, buzz, engine/motor noise,
and, to some degree, music. Convolutional noises include echoes, reverberations, and room
acoustics.
Description of controls (Figure 4-18) is as follows:
Conditional Adaptation:
The Threshold setting has no effect in this case.
Conditional Adaptation allows the adaptive filter to automatically
Adapt/Freeze based upon Master Control Panel bargraph levels.
This can be very useful in situations where there are pauses, or
breaks, in the speech being processed.
Hint: Conditional adaptation is useful in maintaining adaptation once
the filter has converged. Motion in the room and air temperature
changes affect the filter’s operation. First allow the filter to
converge in Always and the click on If Normal Output <
Threshold. Adjust the threshold for adaptation (Adapting
LED is GREEN when adapting) by observing the bargraph
levels when the voice is not present; note that the threshold is
shown on the bargraph along with the audio level, and that the
bargraph corresponds with the Left channel audio in the Stereo,
Linked Input Mode selection.
Figure 4-18 1-Channel Adaptive Filter Control Window