Polycom C16 - Manual (Page 131)

Customizing SoundStructure Designs
5 - 51
• High Pass,
• Low Shelf,
• High Shelf, and
• 10 parametric equalizers
as shown in the following figure.
To enable a filter, click the check box next to the filter. This will make the filter
the active filter and allow the parameters to be changed as shown next.
The cut off frequency can be adjusted between 0 Hz and 20,000 Hz, the order
can be adjusted from 2
nd to 8 th , and either a Butterworth or Linkwitz-Riley
filter may be selected.
For each of the 1 parametric filters, the designer can choose from:
• Parametric filter
• Notch filter
• Allpass filter
Parametric filters emphasize or de-emphasize the center frequency with a gain
and bandwidth setting. The user can specify the bandwidth (in octaves), center
frequency (in Hz), and gain (from 0 to 20 dB).
Notch filters eliminate energy (attenuate only) at the center frequency. The
amount of attenuation for the signal is determined by the bandwidth (in
octaves) selected. The bandwidth is defined as where the gain is -3 dB.