(From TeachEngineering.org. Lesson contributed by the Electrical and Computer Engineering Department, Drexel University GK-12 Program)

Update 1/31/14: Activity and worksheet no longer available on TeachEngineering site. Click HERE for .pdf of original Drexel activity; other sound-related activities can be found HERE on the home page of the then-graduate student who created the sound-booth engineering activity, Travis Doll.

For additional sound or acoustic engineering resources, click HERE for Sound Booth Engineers, a design activity for second grade science students from UNC-Chapel Hill. This Teachengineering.org activity for grades 3-5 on how sound travels includes a worksheet and complements this sound-booth activity. And this 2010 eGFI Teachers’ newsletter has several activities and features on sound engineering.

In this activity, students in grades 7 – 9 explore the sound-dampening ability of numerous materials by designing and prototyping model sound booths. They learn about how sound is reflected and absorbed, and how it travels through various materials, providing an overview of sound dampening, energy absorption, and sound propagation in the context of engineering.

Grade level: 7-9

Time: 3 hours

Learning Objectives

After this activity, students should be able to:

• Explain how surfaces reflect sound waves.
• Develop blueprints for a structure to be constructed.
• Explain why certain materials absorb more sound than others.
• Write a formal lab report.

Standards

International Technology Education Association

• F. Manufacturing systems use mechanical processes that change the form of materials through the processes of separating, forming, combining, and conditioning them. [Grades 6 – 8]
• M. Materials have different qualities and may be classified as natural, synthetic, or mixed. [Grades 9 – 12]

Common Core State Mathematics Standards

• 12. Make formal geometric constructions with a variety of tools and methods (compass and straightedge, string, reflective devices, paper folding, dynamic geometric software, etc.) [Grades 9 – 12]

National Assessment of Educational Progress

• Make estimates appropriate to a given situation by: identifying when estimation is appropriate, determining the level of accuracy needed, selecting the appropriate method of estimation, or analyzing the effect of an estimation method on the accuracy of results. [Grade 8]

Massachusetts Science and Technology/Engineering Standards

• 2.4 Identify appropriate materials, tools, and machines needed to construct a prototype of a given engineering design. [Grades 6 – 8]
• Design and conduct scientific investigations. [Grades 6 -12]
  • Articulate and explain the major concepts being investigated and the purpose of an investigation.
  • Select required materials, equipment, and conditions for conducting an experiment.
  • Identify independent and dependent variables.
  • Write procedures that are clear and replicable.
  • Employ appropriate methods for accurately and consistently
    • making observations
    • making and recording measurements at appropriate levels of precision
    • collecting data or evidence in an organized way
  • Properly use instruments, equipment, and materials (e.g., scales, probeware, meter sticks, microscopes, computers) including set-up, calibration (if required), technique, maintenance, and storage.
  • Follow safety guidelines.

Materials

Introduction/Motivation

Sound booths and sound dampening materials are used in the recording industry to produce high-quality recordings of music that people listen to on iPods (MP3s), CDs, the radio, movies, and via the Internet. Without high-performance sound dampening materials, music tracks would be mixed with environmental background noises from outside recording studios. Imagine if your band rented a practice space in a building with other practice spaces and no sound proofing; the only time you would ever get a chance to practice and only hear your band’s music would be when all other bands were not in the studio!

In our noisy world, we need sound-proofing and sound-dampening capabilities — for musical purposes as well for activities such as conference-room meetings and library studying. Engineers design and create sound dampening structures that are used in recording studios, concert halls, movie theaters, and even hospitals. What are some other spaces where you think sound dampening would be useful?

Procedure

Background. Stand-alone sound booths or sound-isolation booths are built with fairly thick walls of about 3.75-inches (9.5 cm). The interior walls are covered with polyurethane acoustic foam or some other sound-dampening material. The booth’s exterior is covered with an acoustic fabric to dampen the sound. Various other types of materials, such as baffles, ceiling tiles, vinyl barriers, and some rubber products are used to dampen the sound in the booths. In some instances, studio floors are even elevated to detach them from the overall building structures, eliminating more vibrations from entering the recording spaces. Regular rooms can be made more sound proof by adding products to the walls, ceilings, and floors to help prevent outside noises from entering.

Before the Activity

• Gather materials and make copies of the Building a Sound Booth Worksheet, one per group.
• Divide the various supplies into groups.
• Divide the class into teams of three or four students each.

With the Students

1. Ask students which materials would be best for sound dampening and why.
2. Explain to the students that their job is to act as engineers and design and build model sound booths that can dampen the sound generated inside as much as possible, given the materials provided.
3. Hand out the worksheets and have each group complete the Brainstorming section. Make available a sample of each supply material for students to see and touch.
4. Have teams create Blueprint Designs of their sound booths, preparing a detailed list of materials needed on their worksheets.
5. Approve the blueprint design plan from each group only if all supplies are listed with exact amounts and the design is realistic.
6. Once all groups have approved blueprints, demonstrate the correct procedure for cutting the poster board to form the shell of the sound booth, as described on the worksheet.
7. Direct students to trace the outline of the shell on their poster boards.
8. Check each group’s traced outline before allowing them to cut the poster board.
9. Distribute only the materials each group needs to construct its sound booth from its blueprint.
10. Have the teams construct their sound booths with their requested materials only.
11. To simulate a real-world situation, limit how much time students are given to construct their model sound booths.
12. After students have completed their sound booths, it is time to test each group’s prototype.
13. To test a sound booth, place the booth over the audio speaker, like an upside down cup. Place a decibel meter next to the booth.     
14. To make the testing accurate between prototypes, play the same audio clip at the same volume level for each booth test.
15. For each sound booth test, have students record the highest decibel level reached in the table in the Data Collection section on the worksheet.
16. After testing, have each group go to the front of the room and explain the construction of its sound booth and why it was made in that manner.             Image copyright © Travis M. Doll.
17. Have students complete the Analysis and Conclusions sections of their worksheets.
18. Lead a class discussion about why certain sound booths performed better than others and why certain materials work better than others.
19. Assign students to write formal lab reports

Troubleshooting Tips

Often, the bottom edges of students’ model sound booths are not even because of inaccurate booth construction and/or warping of the booth walls from drying glue. The resulting gaps let audio escape when playing the sound file. To create a better seal when testing the sound booths, guide students to (1) be precise in their construction work, and (2) make a homemade device to sit the sound booth down into.

Cut off the bottom of a cardboard box to make a "homemade device" to seat the model sound booth into, thus preventing the loss of audio from under the bottom edges of the booth.

Example of a device to hold the sound booth: Cut off the bottom of a cardboard box, leaving a bit (~3cm) of the sides still on. Flip it over and cut out the inset square for the sound booth. Then place the cut up box upside down on a piece of cardboard and trace the outline to make the bottom of the “homemade device.” Tape it all together with duct tape. Next, fill the inside of this box with tissues or cotton balls. Cut a hole in the side to run the audio cord through.

Investigating Questions

Additional resources:

Sound Booth Engineers. A hands-on design activity for second grade science student from the University of North Carolina, Chapel Hill on NC Learn.

Fantasy Studios. A multimedia tour of the world-class sound recording and production services at the  Zaentz Media Center in Berkeley, Calif. Click on their Gallery link to see photographs of their sound recording studios and control booths.

The National Jukebox. Browse the Library of Congress’s free digital archive featuring more than 10,000 78 rpm disc sides issued by the Victor Talking Machine Company between 1900 and 1925 and learn about the history of acoustical recording, before the invention of microphones and sound studios.

The Beatles recording sessions. EMI Studios Feb, 26-27, 1964 [YouTube B&W clip: 5:10] Hey Bulldog [YouTube, color clip, 3:22]

Build a “Laughing Cup.” In this hilarious activity from the Exploratorium in San Francisco, children 5 to 14 learn about friction and sound by building a Brazilian cuica, or carnival drum, from paper cups and string.

The Sound Site. Learn about the science of sound, add or search for a sound in the online database, or find activites on this Minnesota Museum of Science site.

Sound activities. String telephones, glass harmonicas and more from the U.S. Army Education Command’s Young Engineers’ Club science and engineering pages.

© 2007 by Drexel University GK-12 Program. Click HERE for .pdf

Filed under: Class Activities, Grades 6-8, Grades 6-8, Grades 9-12, Grades 9-12, Lesson Plans

Tags: acoustical engineering, Class Activities, Electrical Engineering, Grades 6-8, Grades 9-12, Lesson Plan, Music engineering, sound, teachengineering