Echo Effects
Eric W. Tarr · 2018
This chapter discusses systems with delay that create echo effects. These effects are categorized by the creation of an audible delay perceived by listeners as an echo. An echo effect is created by using parallel processing such that a delayed signal is combined with the original version. Audio engineers refer to the processed delayed signal as the wet signal and the parallel delayed path as the wet path, or a delay line. An important factor in temporal fusion is a listener&s;s echo threshold. When the time delay between repetitions is less than the echo threshold, one sound is perceived instead of distinct, delayed repetitions. The multi-tap echo is one effect that creates multiple delayed repetitions of an input signal. This effect is implemented using a feedforward design with multiple delay lines in parallel. A different method of creating an echo effect is the feedback echo.