Digital Audio Corporation PCAP II, User Manual

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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 filters
operation. First allow the filter to converge in
Always and the click on If Output <
Threshold . Adjust the threshold for
adaptation (LED is red) by observing the
bargraph levels when the voice is not
present.
Click on the Clear button if you desire the
filter to completely readapt based upon the
new Conditional Adaptation settings.
The Master Control Panel will display an
Adapting indicator for each filter block
whenever
Filter will adapt is set to
anything other than Always . In Stereo,
Linked configuration, two indicators are
provided for each filter block (one LED for
each channel).
Filter Size: Used to set the number of FIR filter taps in
the adaptive filter. Filter size is indicated
both in taps (filter order) and in milliseconds.
Minimum Filter Size is 32 taps, but can be
set to as high as 4096 taps depending on
System Bandwidth, Configuration, and
Number DSP Stages settings.
Normally, the
maximum filter size possible is used in the
2CH adaptive filter
Adapt Rate:
Used to set the rate at which the adaptive
filter adapts to changing signal conditions
(mathematically known as Mu). A Mu of 1 x
2^-14 provides very slow adaptation, while a
Mu of 256 x 2^-14 provides fastest