Delay

Sound is delayed a certain amount of time, and this delayed sound is mixed with the original sound. We hear the delayed sound as an echo.

How does Delay work?
You may draw a breakpoint curve to determine how the delay time will be varied. A feedback value determines the number of echoes (zero feedback gives only one echo).

Values that may be set:
Time determines the delay time.
Feedback determines how of the delayed sound will be sent back through the effect unit. The control curves describe the development of the total sound, but the input sound that is drawn behind them need not be of the same duration.
Mix determines how much of the treated sound is to be used in relation to the original sound.

Special Effects:
If the delay time varies rapidly, the pitch is changed. This is called the Doppler effect.

If the delay time is very small and the feedback is great, the timbre of the sound is changed and may produce a metallic robot sound. This is called a comb filter.

Here are some sounds with delay effects:
Delay
Delay with feedback
Doppler
Comb filter

This is how the voice and the siren sounded without the effects.