This effect generates an echo in your wave file by taking the original sound, reducing its volume, and mixing it back into your audio with a slight delay. As always, you should experiment to see what values work best for different types of files.
Options
Repeat Delay - the amount of delay time between the sound and its echo.
Repeat Strength - the loudness of the echo, as a percentage of the original sound's loudness.
Extend Echo Result by Delay Size - If the resulting Echo seems to end abruptly, enable this option. It provides for a comparitively smoother ending to the echo.
Stereo Options - if the wave file is in stereo, you may select which channel(s) to apply the echo effect to.