Apply a two-pole peaking equalisation (EQ) filter. With this filter, the signal-level at and around a selected frequency can be increased or decreased, whilst (unlike bandpass and bandreject filters) that at all other frequencies is unchanged.
In order to produce complex equalisation curves, this filter can be given several times, each with a different central frequency.
The filter accepts the following options:
- frequency, f
-
Set the filter’s central frequency in Hz.
- width_type
-
Set method to specify band-width of filter.
- h
-
Hz
- q
-
Q-Factor
- o
-
octave
- s
-
slope
- width, w
-
Specify the band-width of a filter in width_type units.
- gain, g
-
Set the required gain or attenuation in dB. Beware of clipping when using a positive gain.
Examples
-
Attenuate 10 dB at 1000 Hz, with a bandwidth of 200 Hz:
equalizer=f=1000:width_type=h:width=200:g=-10
-
Apply 2 dB gain at 1000 Hz with Q 1 and attenuate 5 dB at 100 Hz with Q 2:
equalizer=f=1000:width_type=q:width=1:g=2,equalizer=f=100:width_type=q:width=2:g=-5