User`s manual

Page 28
When the MicroDAC 5 is running standalone (not connected to the PC), the filter
runs at whatever settings are stored in the nonvolatile memory. When running
connected to the PC, finer control is available. Figure 6-2 shows the filter
controls available for the 1CH adaptive filter.
Figure 6-2: 1CH Filter Dialog
Description of the controls pictured in Figure 6-2 follows:
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 16
taps, but can be set to as high as 2048 taps depending on the system bandwidth.
Small filters are most effective with simple noises such as tones and music.
Larger filters should be used with complex noises such as severe reverberations
and raspy power hums.
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
-18
provides very slow
adaptation, while a Mu of 5884 x 2
-18
provides fastest adaptation.