Extron electronics DMP 128 User Manual page 45

Parametric (Equalizer)
The parametric filter is a frequency equalizer that offers control of all parameters, including
amplitude (the amount of gain [boost], or gain reduction [cut] applied), center frequency
(frequency), and range of affected frequencies (Q) around the center frequency. Q is the
center frequency divided by the bandwidth.
Up to five parametric filters can be placed in the filter block at one time, each set to a
different frequency creating a five band parametric equalizer. The control can boost or cut
the center frequency, and by changing the Q value, the range of affected frequencies can be
widened or narrowed around the center frequency. In general, a higher Q value results in a
narrower affected bandwidth.
To demonstrate how Q affects the filter, the following filter block (see figure 31) contains five
parametric filters centered at different frequencies, but with the same Q of 1.0. The filter in
focus ( ) has a center frequency of 1000 Hz boosting that frequency +12 dB over a Q of
3
1.0. Note the markers on either side of the peak frequency are at about 300 Hz on the left
and 3000 Hz on the right, a bandwidth of 2700 Hz.
Figure 31. Parametric Filter at 1000 Hz, Q: 1.000
DMP 128 • Software Control 39