How Guitar Pedals Work

Make It Repeat: Echo and Delay Effects

Foot on guitar pedal
Loops and delays can create otherwordly sounds from your guitar.

As we mentioned earlier when discussing Duane Eddy and his homemade 500-gallon echo chamber, reverb and echo were among the first effects guitarists attempted to engineer. The results, from the very first tape-based echo units to the most advanced looping pedals of today, have done nothing less than change the face of music. Vocalists today wouldn't dream of recording leads without first drenching their dulcet tones in reverb. Listen to U2's guitarist the Edge on "Where the Streets Have No Name," and you'll hear the stunning guitar delay that has influenced a whole generation of new players. Finally, modern looping pedals have enabled performers like Theresa Andersson to elevate the traditional singer-songwriter experience to a new level by using a variety of instrument and vocal loops performed live.

Here's how some of the most classic time-based effects work:


  • Echo. Want to sound like you're playing inside the National Cathedral in Washington, D.C., minus the cathedral? Use an echo effect. Vintage analog echo effects, such as the Roland RE-201 Space Echo, are highly coveted and still in use today.
  • Delay. Delay pedals can ping back a signal with a very short delay, similar to echo, or with such a long delay that you can play a new melody over the top of the original one. Delay (and its hippie cousin, Reverse Delay) can also produce a variety of interesting noises. The band Pomplamoose twists the knob on an Electro-Harmonix Deluxe Memory Man pedal in its rendition of Beyonce's "Single Ladies" to create needle-on-the-record DJ sounds.
  • Chorus. Chorus is an effect that splits a signal and then slows and slightly detunes half of it before mixing it back in with the unaffected half. You can hear chorus on "She Sells Sanctuary" by The Cult and "Come as You Are" by Nirvana.
  • Reverb. Reverb is a sort of echo-upon-echo effect; each echo decays at a different rate, making the signal sound like it's bouncing around (reverberating) in an empty room.
  • Looping pedals. Like delay pedals on steroids, looping pedals enable guitarists to layer multiple phrases on top of each other to create interesting musical textures. Musicians like Andrew Bird and Howie Day is known for looping pedals.

You've affected a signal's volume, messed with its pitch and made it repeat itself. What territory is there left to explore? One word: frequency. Discover filter effects and everything else on the next page.