Echo (also called long delay) is a natural effect as well, but it can only be encountered in large spaces such as canyons or maybe a large, empty stadium. You emit a loud, sharp yelp and a second later you hear the yelp come bouncing faintly back to you from a far wall. This is a particularly fun effect to play around with by yourself. If you set the delay long enough, you can play against the notes you just played and harmonize with yourself while the rate sets up a kind of beat.
Echo controls usually let you determine the level, the period between playbacks, and the decay—the rate at which succeeding notes get quieter and quieter before they fade out altogether. The period (or time) parameter is often controlled by a single button you push repeatedly in time with the music. This is called tap delay and keeps your echo effect from clashing with the music's time signature.
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| Chorus Pedal |
Chorus is the most common modulation effect—even appearing as the sole effect on a number of amps—and is generally the most subtle. As it is usually applied, chorus sounds like the same signal running through two amps with a very slight delay between them. In fact, Pat Metheny's famous chorus sound is produced in exactly this manner, using no actual chorus effect at all.
Chorus is a great way to thicken up the sound of a bass (especially in a 3-piece band), rhythm guitar, or solo guitar. It is often used with distorted sounds but is a fantastic way to create full-sounding clean runs as well. Stereo output (from two separate speakers) enhances chorus a great deal.
