Michael Fitzpatrick: One of the research endeavors that I took was to look into the ideal sound wave rate, the idea of a vibrato wave, of oscillation, and there was a study that analyzed the great musicians of the past 20th century: Caruso, Heifetz, Casals, and they all have a vibrato wave or rate that was about 7 or 8 cycles per second.

So you have this—ning, ning, ning, ning—ning, ning, ning, ning– ning, ning, ning, ning—and the physicist will attest to that we are entrained to the vibration that is dominant in our environment sonically.

So I was then curious to know if somehow this was a deeper universal rhythm that they were tuning into. If you can tap into that universal pulse, if you can get that to come out of the instrument that other people would experience that directly.

You hit that pulse right on, then—whatever word you want to use—you can experience peace of mind, enlightenment, or just deep listening

Lesson Plans:

• Experimental Music
• We’ve Got Rhythm
• Good Vibrations

We’ve developed core tools around the concepts of chords, frequency, and rhythm in partnership with Indaba Music. These tools incorporated in the lesson plans can also be appreciated on their own! Feel free to check out these fun interactives below.

Learn about basic chord stucture:

Learn about frequency and how it manifests in sounds the sounds around us:

Learn about how rhythm can manifest itself in the environment:

2) Load the “Frequency Explorer” widget from the MUSIC INSTINCT Web site. Play each sound in turn with the widget on the default (“reset”) settings, and then adjust the settings to emphasize higher, treble frequencies (on the right) and lower, bass frequencies (on the left). Ask students to describe how the quality of each sound is affected by adjusting the settings in different ways. For instance, does a cheering crowd sound nearer or further away without treble? (Further.) What might be deduced from this? (Higher frequencies don’t travel as far.) Can the sounds of an indoor shower be made to sound like rain outside? Can it be made to sound like an egg frying? (Accept all answers.)

2) Review the focus question: how does Evelyn Glennie experience music? (She feels it through the sounds vibrations in her body.) Explain that the human body itself is a medium through which sound travels as described in the introductory activity. Log on to the “Introduction To What Sound Is” website (www.fearofphysics.com/Sound/dist.html). Have the students click “Play” for the animation and explain that the first page of this website depicts, like the Slinky demonstration, a sound wave in a single, straight-line pulse. Have students click on the blue link at the bottom of the yellow box (“The wave is able to spread out more…”) and explain this second page of the website (“Sounds: Allow the Wave to Expand”) illustrates a sound wave in two dimensions. Ask students to review what the red dots in each illustration represent. (The molecules of the medium.) Minimize the browser window with this website, as you’ll be returning to it later in the lesson.

3) Divide the class into groups of 3-5, and explain that each group will be conducting a series of experiments to determine how sound travels though different mediums. Distribute a wire hanger, a metal spoon, some yarn, some string, some metal wire, a ruler and the “Sound Mediums” Student Organizer (PDF) (RTF) to each group. Each member of the group should hold the wire hanger and tap it with the ruler. The group should collectively agree on how to describe the sound, and enter this description on the student organizer.

4) Next, tie a four foot length of string onto the hook of the hanger. Have each group member in turn wrap a few inches of each string around a finger on each hand. Gently plug the string-wrapped fingers into each ear. Have another person tap the hanger with the ruler. How is the sound different than before? Enter a collective description on the student organizer.

5) Replace the string with a four foot length of yarn. How do the sounds compare to those when string was used? Replace the yarn with a four foot length wire. How does that compare? Replace the four foot wire with a six foot wire. Does length affect loudness? Why? Have the group note all their collective responses on their student organizer.

6) Have each group take turns reporting their findings as recorded on their student organizers. Explain that the speed at which sound travels depends on the medium in which it is traveling and the molecular packing of that material. Molecules are packed most densely in solids and least densely in gases. The closer the molecules are together, the better sound travels. In this activity, when the string and fingers were plugged into the ears, the sound traveled better than just through the string and air. Solid wire is a denser, better conductor of sound than tightly woven string, which is in turn a better conductor of sound than loosely woven yarn.

7) Tell students that so far they’ve been learning about how sound moves from an initial source vibration through a medium. But what happens when a sound wave actually reaches our ear? What enables us to hear sound, and distinguish between different sounds? (Accept all answers.) Provide a FOCUS question for the next video clip by asking students what the cochlea is and how it works. PLAY Clip 3, “How We Hear”

Review the focus question: what is the cochlea and how does it work? (The cochlea is a snail-like part of the ear filled with tiny hair cells which are tuned to vibrate at different frequencies. The cochlea converts these physical vibrations into electromagnetic signals to the brain’s auditory cortex.) Explain that the pitch we hear is directly related to the speed, or frequency, of the sound wave.

9) Log on to the “Pitch, Notes, and Duration” activity page (http://www.bbc.co.uk/music/parents/activities/musicsense/ms2.swf). Ask students to compare the speeds of the two pitches they hear—what can they conclude? (That higher pitches have faster speeds of vibration.) Now restore the “Introduction to What Sound Is” website and click to the next (third) page of the site (also directly accessible at http://www.fearofphysics.com/Sound/dist_hear.html). Ask what a Hertz measures (The number of vibrations per second).

10) Explain that the range of sound frequencies generally audible to humans varies among individuals, and particularly with age. Allow students to discover the limits of their own hearing by directing them to the “Hearing Test” available at http://www.freemosquitoringtones.org/. Invite one student to sit at the computer hidden from view. Tell the student that he or she should activate the tones at irregular intervals, beginning with the lowest frequencies and moving progressively higher. Ask everyone else in the room to stand up, close their eyes, and only sit down when they are sure they can no longer hear the activated pitch. You play too!

11) Explain that frequencies higher than humans can hear are referred to as ultrasonic, while those too low for humans to hear are called infrasonic. Provide a FOCUS question for the next video clip by asking students what infrasonic pitch the black hole described in the clip makes.  PLAY Clip 4: “Cosmic Music.”

12) Review the focus question: What pitch does the black hole described in the clip make? (B flat—but 57 octaves too low for us to hear.) The video clip referred to sound as a “unifying thread” connecting everything in the universe. Explain that the final clip will approach that same theme from a different angle. Provide a FOCUS question by asking students what similarities may be found between the sounds made by whales and those made by catbirds. PLAY Clip 5: “Whale Song.”

13) Review the focus question: what similarities may be found between the sounds made by whales and those made by catbirds? (The whale song, when sped up, has a similar pattern and form to the birdsong). Ask students why they think this might be? (Accept all answers, but suggest that the longer, slower, lower whale song may reflect whales’ larger size and slower metabolisms compared with the higher speed, more tightly wound metabolisms of small birds, and that the lower, slower whale song may be better suited to travel through the denser medium of water.)

2) Tell students that what they are doing with the Slinky is modeling the way energy in the form of a sound wave travels through solids, liquids or gases. Explain that those substances, known as mediums, are composed of molecules, more or less regularly spaced from each other, like the coils of the Slinky.  When one of these molecules begins to vibrate as the result of a sound source’s energy, it pushes against the molecules next to it (a process called compression) before returning to its original position (a process called rarefaction); the process is repeated with the adjacent molecules and so on as the sound wave passes through the molecular structure of the medium.

3) Tell the class they will now be looking at the first of several clips about sound from the PBS program THE MUSIC INSTINCT. Provide a FOCUS for media interaction by asking students how the physical nature of a musical note on a cello differs from that of a handclap. PLAY Clip 1: “The Nature of Vibration.”

4) Review the focus question: how does the physical nature of a musical note on a cello differ from that of a handclap? (A sustained musical note repeats in a regular, cyclical pattern of pressure waves. A handclap is more sudden and chaotic.) Ask students how a cello note and a handclap could be simulated with the Slinky, and have the volunteers perform the simulations as suggested. (A cello note could be simulated by pulsating one end of the Slinky back and forth in a rhythm; a handclap can be simulated by a single powerful push or spasm.)

Preview all of the video segments and Web sites used in the lesson.

Download the video clips used in the lesson to your classroom computer, or prepare to watch them using your classroom’s Internet connection.

Bookmark the Web sites used in the lesson on each computer in your classroom. Using a social bookmarking tool such as del.icio.us or diigo (or an online bookmarking utility such as portaportal) will allow you to organize all the links in a central location.

Make sufficient copies of the “Sound Mediums” Student Organizer (PDF | RTF)

Content Standard A
As a result of activities in grades 5-8, all students should develop

• Abilities necessary to do scientific inquiry
• Understandings about scientific inquiry

Content Standard B
As a result of their activities in grades 5–8, all students should develop an understanding of:

• Properties and changes of properties in matter
• Motions and forces
• Transfer of energy

National Standards for Arts Education: Music:
http://artsedge.kennedycenter.org/teach/standards.cfm?subjectId=MUS&gradeBandId=&sortColumn=&x=8&y=3

Content Standard 6: Listening to, analyzing, and describing music
Grades 5-8 Achievement Standard

• Students demonstrate knowledge of the basic principles of meter, rhythm, tonality, intervals, chords, and harmonic progressions in their analyses of music

Materials
For the class:

• Computer with internet access and audiovisual projection system
• Slinky™

For each group of several students:

• Wire hanger
• String (precut to one 4 foot length for each group)
• Yarn (precut to one 4 foot length for each group)
• Metal wire (precut to one 4 foot length and one six foot length for each group)
• Ruler
• “Sound Mediums” Student Organizer (PDF) (RTF)

Objectives
Students will be able to:

• Define key terminology about sound
• Describe the movement of sound waves through various mediums and how different sounds produce different types of waves
• Understand that the human body is itself a medium through which sound and music may be appreciated by a deaf person
• Explain how sound is generally perceived by the ear and transmitted to the brain
• Understand that the audible spectrum of sounds which humans can hear is a small part of an overall frequency spectrum of ultrasonic and infrasonic sound

“Pitch, Notes, and Duration”
www.bbc.co.uk/music/parents/activities/musicsense/ms2.swf
A simple animation of how lower frequencies have longer, slower wavelengths.

“Hearing Test”
www.freemosquitoringtones.org/
Challenges visitors to test the upper registers of their audible spectrum, which decreases with age.

2) “An Ocean of Vibration”
A description of how deaf percussionist Evelyn Glennie is able to experience sound as vibrations in her body:

3) “How We Hear”
A description of the how humans hear, from the ear drum to cochlea to brain:

4) “Cosmic Music”
An exploration of the tones found in the larger universe:

5) “Whalesong” An exploration of the tones found in the larger universe.
An analysis of whale song comparing its structure to that of birds, and perhaps to universal patterns and forms: