3 Equalizer

The equalizer filters are used to make the loudspeaker response flat and also to compensate for any non-linear distortion such as speaker rub-and-buzz.

The equalizer filters consist of multiple biquad filters allowing the following:

• Loudspeaker frequency response compensation
• Extend the bass response of the speaker
• Attenuate frequencies that produce high THD
• Remove dc signals or very low frequency signals that may cause speaker damage due to over excursion

The static filter chain consists of a 10-biquad equalizer filter module and a high-pass filter module.

Figure 3-1 Equalizer and High-Pass Filter Controls for Static Equalizer

The High-Pass filter module removes dc signals. The corner frequency, order of the filter, and the type of filter are programmable.

The equalizer filter consists of 10-biquad filters. Each filter can be programmed with different filter types (high pass, low pass, equalizer, and so forth) and with different parametric options (corner frequency, bandwidth, gain, Q-factor, and so forth).