User`s manual

very slow adaptation, while a Mu of 3808 x 2

-14

provides fastest

adaptation.* As a rule set this rate to approximately 100-200 initially, to

establish convergence, then back off to a mid value to maintain

cancellation.

Auto Normalize: Selects Normalized (LED illuminated GREEN) or Fixed (LED not

illuminated) adaptation rate. Normalized is recommended. When Auto

Normalize is enabled, the specified Adapt Rate is continuously power

scaled based upon the input signal level. This generally results in faster

convergence for a given Mu. When Auto Normalize is not enabled, the

specified Adapt Rate is utilized at all times without power scaling

Delay Channel: Specifies whether the delay line is to go into either the Primary (Left)

channel or the Reference (Right) channel. For most applications , a

slight delay (typically 5 msec) is placed in the Primary channel, For

applications with long distances between the mike and radio/TV, a delay

in the Reference channel may be required. Extreme caution should be

exercised when using reference channel delay; excessive delay in that

channel will not allow cancellation to take place.

Delay: Sets the number of audio samples in the delay line. Delay is indicated

both in samples and in milliseconds. Minimum Delay is 1 sample, but

can be set to as high as 32768 samples depending on Configuration and

Number DSP Stages settings.

Processor Output: Selects Residue or Filter output. The Residue output is the normal

output selection, which is the signal left over after the Reference signal

has been cancelled from the Primary signal. The Filter ouput is the

modified Reference signal being subtracted from the Primary signal.

Filter Button: Used to switch the Reference Canceller filter in and out of the process

without affecting the other filters in the process. The Filter LED

indicates that the filter is “in” when it is lit RED. The filter is out of the

process when the Filter LED is unlit.

Adapt/Freeze Button: Used to freeze this adaptive filter independently. The filter is adapting

when the Adapt LED is lit. The filter is frozen when the Adapt LED is

unlit.

Clear Button: Used to reset the coefficients of the Reference Canceller to zero without

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-14

is a means of expressing 2 raised to the –14

power, which equals 0.000061; 256 x 2

-14

is, therefore, equal to

0.016.