The Chorus effect creates an echo effect which, when applied to a recorded voice, makes it sound like there is a choir singing in the background.  
The following sliders are available in the Modulation area:
Depth

Specifies the degree of the change in pitch.

Frequency

Specifies the frequency of the change in pitch (oscillations).

The following slider is available in the Delay area:
Delay

Specifies the delay with which the copy is played in comparison with the original signal.

The following setting options are available in the Filter area:
Check box
Low Pass

Activates a low pass filter.

Slider
Low Pass

Reduces frequencies above the specified Hertz rate and allows low frequencies beneath the specified value to pass almost unfiltered.

The following sliders are available in the Mix area:
Effect

Mixes the original signal with the copied signal, indicating the intensity of the copied signal.

Dry Signal

Mixes the original signal with the copied signal, indicating the intensity of the original signal.

The following option buttons are available in the Chorus area:
Mono/Stereo

Gives the processed part of the audio file a more “mono-like” or “stereo-like” sound respectively.

 
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.


Chorus