Digital Audio Corporation PCAP II, User Manual

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To set the upper and lower frequency limits,
use the horizontal scroll bars to position the
two red markers on the Filter Display to the
desired frequency positions.
NOTE: You must use the scroll bars; you
cannot click the mouse at the desired points
in the Filter Display area.
Output Shape
Specifies the final reshaping curve to be
Block: applied to the entire SIFfilter. For Attack
Noise only Flat should be used. For
Equalize Voice three curves are available
and include Flat (no reshaping), Voice
(6dB/octave rolloff above and below 500 Hz),
and
Pink (3dB/octave rolloff above 100 Hz).
The Voice and Pink curves are provided to
reshape the resultant audio power spectrum
to that of a typical voice spectrum; the
Voice curve provides "hard" reshaping, while
the Pink curve provides softer reshaping of
the spectrum.
Build Button:
Builds the spectral inverse filter based on the
original input audio spectrum and the SIF
control settings. When clicked, the mouse
cursor will change to an "hourglass" shape,
indicating that the PC is busy calculating the
spectral inverse filter coefficients and
sending them to the external processor.
When the filter build is complete, the mouse
cursor will return to normal and the
calculated spectral inverse filter curve will be
displayed as a blue trace in the Filter
Display area.
Hint: Before clicking the Build button, it is
recommended that the spectrum analyzer be
set to
Freeze to allow experimentation with
the control settings for the same input
spectrum.