Authentic Lessons for 21st Century Learning

Make Some Waves

Exploring Wave Interference with Synthesizers

James Doyle, Heather Shaffery, Ryan Rahhal | Published: November 11th, 2022 by K20 Center


In this lesson, students will examine the physics behind synthesizers and utilize that knowledge to create unique sounds on a virtual synthesizer. This lesson explores both scientific and musical concepts, and could be utilized in both science and music classrooms.

Essential Question(s)

How do synthesizers manipulate the properties of waves to create different sounds?


  • Internet connected devices like iPads or Laptops

  • headphones


10 Minute(s)

Use the attached lesson slides to guide the lesson.

Display slides 2-4 and discuss the Essential Questions and Lesson Objectives.

Display slide 5 and instruct students to navigate to the Wakelet choice board.

Have students spend about 5-7 minutes watching the videos or video sections of their choice. The options include songs, "making of" videos, and introductions to a few famous synthesizers. Emphasize that student's know that this time is exploratory and low-stakes, and they shouldn't be concerned if they run into vocab or concepts they're not sure about.


20 Minute(s)

Distribute the "Stop and Jot Handout." Display slide 6 and introduce the Stop and Jot strategy. Have students follow the instructions on the slide, navigating to the Chrome Music Labs website on their devices and answering the question on the handout.

Display slide 7. Instruct students to follow the directions on the slide, navigating to the Izotope article on their devices and using the reverse side of the handout to summarize each section.


20 Minute(s)

Display slide 8 and have students navigate to the Wave Addition and Interference simulation. Instruct students to experiment with the "Standing T", "Destruct", and "Construct" modes by adjusting the wave property sliders for either or both waves (frequency, wavelength, velocity, amplitude). The third wave (1 + 2) is the "wave sum" and shows the actual wave produced when the two individual waves interact. Students should be looking for patterns in how the two waves interact with one another.

Display slide 9.

After students have had some time to explore the simulation, discuss the following questions as a class:

  • What happens when two crests pass each other? Two troughs?

  • How does the wave sum change when crests and troughs do not align perfectly?

  • How does changing the amplitude affect the wave sum? The frequency? The wavelength?

Go to slide 10. Introduce the concepts of wave interference, principle of superposition, destructive interference, and constructive interference. Display slide 11. Refer back to the Explore reading. Ask students how wave interference relates to what they read about how synthesizers use oscillators. Guide students to the conclusion that synths work by using wave interference to produce different waveshapes (i.e., stacking oscillators), and that these are called additive synthesizers.


30 Minute(s)

Display slide 12 and read the slide.

Display slide 13 and play the video. Instruct students to navigate to the Cardboard Synth website and plug in their headphones. (

Upon getting to the website and applying their headphones, have students manipulate the synth's parameters in order to create a sound that best represents the word "happy" to them. Using the Airplane Landing strategy, select three students to share their sounds with the class. After a brief discussion, remind students that they can have different ideas on how to represent the words, have them repeat the activity with the following words: angry, growl and sleepy.


10 Minute(s)

Distribute the Reflection handout. Display slide 15. Using the Exit Ticket instructional strategy, have students respond to the following questions and submit their responses on the way out.

What did you change to make each patch sound? Why did you select those parameters? What does changing the frequency do? The wavelength? The amplitude?