Electronic echo (6)
I believe the answer is:
reverb
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">electronic echo</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for reverb that I've seen before include "music made by this device" , "Musical effect produced via an amplifier" , "Echoing effect" , "Echoing device" , "Electronic effect added to music" .)