 Applications and variants       Doubling echo Doubling echo is produced by adding short delay to a recorded sound.
<meaning-changed>  Applications and variants       Doubling echo Doubling echo is produced by adding short delay to a recorded sound.
 Applications and variants Haas effect Short delays (50ms or less) create a sense of "broadening" the sound without creating a perceptible echo, and can be used to add stereo width or simulate double-tracking (layering two performances). The effect is known as the Haas effect after the German mathematician Helmut Haas. Doubling echo Doubling echo is produced by adding short delay to a recorded sound.