The Wah-Wah effect allows you to distort the recording of a guitar.   
The following setting options are available in the Modulation area:
Slider
Modulation Frequency

Specifies the frequency of the modulation.

Drop-down menu
Modulation Function

Selects the signal form of the modulation signal.

The following sliders are available in the Mix area:
Dry Signal

Mixes the original signal with the edited copy, indicating the intensity of the original signal.

Effect

Mixes the original signal with the edited copy, indicating the intensity of the edited signal.

The following sliders are available in the Filter area:
Lower Limit

Defines the lower limit for the frequency.

Upper Limit

Defines the upper limit for the frequency.

Bandwidth

Defines the bandwidth of the frequency.

Feedback

Specifies the number of copied signals.

 
Frequency
The frequency denotes the oscillations per second of an electrical or magnetic field. With audio files this means that the frequency increases with rising pitch. The unit is Hertz (Hz). The highest magnitude of oscillation is called the amplitude.


Wah-Wah