Jump to main content

Designing a Speaker for Bass or Treble

96 reviews


Areas of Science
Time Required
Average (6-10 days)
Material Availability
A kit for this project is available from our partner Home Science Tools. See the Materials section for details.
Average ($40 - $80)
Always keep speaker volume at safe levels to avoid hearing damage.
Ben Finio, PhD, Science Buddies

Recommended Project Supplies

Get the right supplies — selected and tested to work with this project.

View Kit

*Note: For this science project you will need to develop your own experimental procedure. Use the information in the summary tab as a starting place. If you would like to discuss your ideas or need help troubleshooting, use the Ask An Expert forum. Our Experts won't do the work for you, but they will make suggestions and offer guidance if you come to them with specific questions.

If you want a Project Idea with full instructions, please pick one without an asterisk (*) at the end of the title.


Whether you have already tried the Science Buddies Build a Paper Speaker activity or the Measure the Frequency Response of a Paper Speaker project, or you just like music and are interested in exploring more about the science of sound, then this project is for you.

You probably know that sound waves can have different frequencies. If not, you can read more about that in the background section of the Measure the Frequency Response of a Paper Speaker project. The range of human hearing is typically about 20 hertz (Hz) to 20,000 Hz. Frequencies at the lower end of this range are typically referred to as bass, the higher end is called treble, and those in the middle are called mid-range. Ideally, a single speaker would be able to play sounds at all frequencies "equally," meaning it would not make certain frequencies sound louder than others. However, this is not the case. Many times speakers are separated into tweeters for playing high frequencies and woofers for playing low frequencies. Why is this necessary?

The reason has to do with a concept called resonant frequency, sometimes called "natural frequency." Every mechanical system or object has a natural frequency at which it "likes" to vibrate. In general, smaller, lighter, and stiffer objects like to vibrate faster than bigger, heavier, and softer objects. For example, imagine "pinging" a small metal object (like a ruler or paperclip) by flicking it with your finger. It will vibrate back and forth very quickly—possibly faster than your eye can see. Now, think about much larger objects, like tree branches swaying in the wind; they rock back and forth very slowly. The same concept applies to speakers—smaller, lighter tweeters will vibrate at higher frequencies, while larger, heavier woofers will vibrate at lower frequencies.

A graph of the amplitude of a vibration versus the frequency of the vibration is called a system's frequency response. A good speaker should have a frequency response that is as "flat" as possible, meaning it reproduces frequencies at the same volume at which they were recorded. Otherwise, large peaks or valleys in the frequency response will result in some frequencies sounding much louder or quieter than others. Figure 1 shows an example frequency response for a set of computer speakers.

Example graph plots the volume and frequency recorded from a speaker

The example graph shows the frequency response of a set of computer speakers. The graph shows that at a low and high frequency (20, 20000 Hz) the volume level is roughly the same. The frequencies between about 90-18,000 produce a large increase in volume that can fluctuate between 40 and 80 decibels.

Figure 1. Frequency response for a pair of computer speakers. Notice that the x-axis of a frequency response is typically plotted using a logarithmic scale, due to the large range of frequencies for human hearing.

There are many science projects you can do involving the frequency response of speakers. Here are just a few ideas:


Materials and Equipment Buy Kit

Recommended Project Supplies

Get the right supplies — selected and tested to work with this project.

View Kit

icon scientific method

Ask an Expert

Do you have specific questions about your science project? Our team of volunteer scientists can help. Our Experts won't do the work for you, but they will make suggestions, offer guidance, and help you troubleshoot.


If you like this project, you might enjoy exploring these related careers:

Career Profile
Just as a potter forms clay, or a steel worker molds molten steel, electrical and electronics engineers gather and shape electricity and use it to make products that transmit power or transmit information. Electrical and electronics engineers may specialize in one of the millions of products that make or use electricity, like cell phones, electric motors, microwaves, medical instruments, airline navigation system, or handheld games. Read more
Career Profile
Any time you hear music at a concert, a live speech, the police sirens in a TV show, or the six o'clock news you're hearing the work of a sound engineering technician. Sound engineering technicians operate machines and equipment to record, synchronize, mix, or reproduce music, voices, or sound effects in recording studios, sporting arenas, theater productions, or movie and video productions. Read more
Career Profile
Ever wondered who makes sure the Jumbotron works at the super bowl? Or that the microphones work at a presidential inauguration? These are the tasks of an audio and video equipment technician. Audio and video equipment technicians work to set up and operate audio and video equipment, including microphones, sound speakers, video screens, projectors, video monitors, and recording equipment. Read more
Career Profile
Electrical engineering technicians help design, test, and manufacture electrical and electronic equipment. These people are part of the team of engineers and research scientists that keep our high-tech world going and moving forward. Read more

Contact Us

If you have purchased a kit for this project from Science Buddies, we are pleased to answer your questions.

In your email, please follow these instructions:
  1. What is your Science Buddies kit order number?
  2. Please describe how you need help as thoroughly as possible:


    Good Question I'm trying to do Experimental Procedure step #5, "Scrape the insulation from the wire. . ." How do I know when I've scraped enough?
    Good Question I'm at Experimental Procedure step #7, "Move the magnet back and forth . . ." and the LED is not lighting up.
    Bad Question I don't understand the instructions. Help!
    Good Question I am purchasing my materials. Can I substitute a 1N34 diode for the 1N25 diode called for in the material list?
    Bad Question Can I use a different part?

Contact Us

News Feed on This Topic

, ,

Cite This Page

General citation information is provided here. Be sure to check the formatting, including capitalization, for the method you are using and update your citation, as needed.

MLA Style

Finio, Ben. "Designing a Speaker for Bass or Treble." Science Buddies, 13 Feb. 2023, https://www.sciencebuddies.org/science-fair-projects/project-ideas/Phys_p102/physics/speakers-frequency-response. Accessed 26 Sep. 2023.

APA Style

Finio, B. (2023, February 13). Designing a Speaker for Bass or Treble. Retrieved from https://www.sciencebuddies.org/science-fair-projects/project-ideas/Phys_p102/physics/speakers-frequency-response

Last edit date: 2023-02-13
Free science fair projects.