User`s manual

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The Spectral Graphic Equalizer is essentially a 115-band graphic equalizer; however, instead of
having 115 separate slider controls, it allows the user to precisely draw the desired filter shape on
the computer screen, using the mouse, with as much or as little detail as desired..
The Edit feature allows the user to make readjustments to the filter shape, while the Normalize
button allows the user to shift the entire filter curve up until the highest point is at 0dB.
Figure 7-17: Spectral Graphic Equalizer Window
Description of controls/indicators is as follows:
Filter Display: Graphically displays the current shape of the filter. Also used in conjunction
with the mouse to draw a new filter shape or to edit an existing one (see
New, Edit, and Normalize button descriptions). A grid is provided to assist
the user in visually judging frequency and attenuation at any point in the
display.
Freq and Atten Used to precisely readout the frequency in
Readouts: Hertz and attenuation in dB at any point in the filter curve. Hold the left
Mouse button down while editing the curve or drawing a new curve. These
readouts below the grid indicate precise frequencies and attenuations.
Releasing the button draws the segment.
The New, Edit, and Normalize buttons are used to graphically manipulate the shape of the filter curve.
Their functions are complex, and thus are best illustrated in the following mini-tutorial:
1. From the MicroDAC IV Filter Configuration Tabs, select the Spectral Graphic Equalizer for
Stage 1 of any filter. Set the AGC setting to No AGC.
2. Click on the Control button for Stage 1 to bring up the Spectral Graphic Equalizer control
window. When used for the first time, the control window will be the that of the previous
figure.
3. Click on the New button to draw a new filter. The screen will now appear as follows:
Figure 7-18: New Spectral Graphic Equalizer Display
Had you accidentally clicked the New button, you could click on Abort to restore the previous
filter.
4. You should now notice that all the buttons on the control window have been replaced by a
simple Abort botton. Clicking on Abort at any time prior to completing the curve draw
restores the previous filter..