How to Build a Chorus Pedal for a Guitar

By Rupinder Dhillon ; Updated September 15, 2017

Things Needed

  • Chorus effect schematic
  • Electronic components
  • Graph paper or graphic design software
  • Solder
  • PCB or perfboard
  • Soldering iron
  • IC sockets (one per IC chip)
  • Multicore wire
  • Metal switch
  • Ruler
  • Metal enclosure
  • Marker
  • Drill
  • Drill bits (various sizes)
  • Cloth
  • Knobs (one per potentiometer)
Use a strong, durable metal enclosure that can withstand your weight.

The chorus effect makes an instrument sound fuller by making a single voice sound like multiple voices. The effect is achieved with delays, frequency shifts, amplitude modulation or any combination of these effects. The chorus effect has been used by many legendary guitarists, including Jimi Hendrix and Kurt Cobain. You can build a chorus effect pedal at home using a copyright-free schematic from the Web or a book.

Choose a chorus effect schematic that has been tried and tested. Schematics in educational books should work. If you find a schematic online, look for reviews.

Draw a layout of the circuit on a piece of graph paper or in a graphic or circuit design program. The layout shows you where each component is soldered onto the PCB or perfboard.

Solder the electronic components to the PCB or perfboard with your soldering iron. Use your circuit layout as a guide. Solder components, such as diodes, quickly to avoid damaging them. Solder IC sockets to the board. Do not solder chips directly to the board. Use multicore wire to connect components that cannot be soldered directly to the board, such as potentiometers and the metal switch.

Measure the length, width and height of your PCB or perfbaord with a ruler. These are the minimum dimensions of the circuit's metal enclosure.

Measure the width of the circuit's external components. These are the components that you access and manipulate, such as potentiometers, sockets and switches. Measure the part of the component that sticks out of the enclosure. For example, the potentiometer's shaft sticks out of the enclosure; measure the width of the shaft.

Mark the locations of the external components on the metal enclosure with a marker. Write down the size of each component. Choose locations that make it easy for you to interact with the switches, knobs and sockets.

Drill holes in the marked locations of the enclosure. Use drill bits that match the sizes of the components, or are slightly bigger.

Clean debris off the metal enclosure with a cloth.

Place the circuit inside the enclosure. Pull the external components through their holes. Mount the external knobs, switch covers and socket covers.


If you have never built a circuit before, purchase a DIY chorus effect kit. Test the circuit by constructing it on a breadboard and running an audio signal through it before building it on PCB or perfboard. Paint the enclosure and use stickers or screen printing to name each knob's function.


Powering the circuit while you are building it or placing it in its enclosure may result in electrocution.

About the Author

Rupinder Dhillon is an electronic artist, sound engineer and professional writer, specializing in technology. Her research has been published by the Association for Computing Machinery and College Art Association. She holds a Master of Fine Arts in digital arts from University of California, Santa Cruz, and a Bachelor of Science in music technology from London Metropolitan University.