Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds...
-
Upload
rudolph-hoover -
Category
Documents
-
view
217 -
download
1
Transcript of Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds...
![Page 1: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/1.jpg)
Chapter 17Chapter 17
Section 2Section 2
![Page 2: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/2.jpg)
What is music?• Music and noise are groups of sounds.• Music is a group of sounds that have been
deliberately produced to make a regular pattern.
MusicMusic
22
![Page 3: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/3.jpg)
What is music?• The sounds that make up music usually have
a regular pattern of pitches, or notes.
MusicMusic
22
• Noise is usually a group of sounds with no regular pattern.
![Page 4: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/4.jpg)
Natural Frequencies• Music is created by vibrations.
MusicMusic
22
• If you tap on a bell with a hard object, the bell produces a sound. When you tap on a bell that is larger or smaller or has a different shape you hear a different sound.
![Page 5: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/5.jpg)
Natural Frequencies
• The bells sound different because each bell vibrates at different frequencies.
MusicMusic
22
• A bell vibrates at frequencies that depend on its shape and the material it is made from.
• Every object will vibrate at certain frequencies called its natural frequencies.
![Page 6: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/6.jpg)
Musical Instruments and Natural Frequencies
• Many objects vibrate at one or more natural frequencies when they are struck or disturbed.
MusicMusic
22
• Musical instruments use the natural frequencies of strings, drumheads, or columns of air contained in pipes to produce various musical notes.
![Page 7: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/7.jpg)
Resonance
• Sometimes sound waves cause an object to vibrate.
MusicMusic
22
• When a tuning fork is struck, it vibrates at its natural frequency and produces a sound wave with the same frequency.
![Page 8: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/8.jpg)
Resonance
• Suppose you have two tuning forks with the same natural frequency.
MusicMusic
22
• You strike one tuning fork, and the sound waves it produces strike the other tuning fork.
• These sound waves would cause the tuning fork that wasn’t struck to absorb energy and vibrate.
• This is an example of resonance.
![Page 9: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/9.jpg)
Resonance
• Resonance occurs when an object is made to vibrate at its natural frequencies by absorbing energy from a sound wave or another object vibrating at these frequencies.
MusicMusic
22
• Musical instruments use resonance to amplify their sounds.
![Page 10: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/10.jpg)
Overtones
• A tuning fork produces a single frequency, called a pure tone.
MusicMusic
22
• The notes produced by musical instruments are not pure tones.
• Most objects have more than one natural frequency at which they can vibrate.
• As a result, they produce sound waves of more than one frequency.
![Page 11: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/11.jpg)
Overtones
• If you play a single note on a guitar, the pitch that you hear is the lowest frequency produced by the vibrating string.
MusicMusic
22
• The lowest frequency produced by a vibrating object is the fundamental frequency.
• The vibrating string also produces higher frequencies.
![Page 12: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/12.jpg)
Overtones
• These higher frequencies are called overtones.
MusicMusic
22
• Overtones have frequencies that are multiples of the fundamental frequency.
![Page 13: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/13.jpg)
Overtones
MusicMusic
22
• The number and intensity of the overtones produced by each instrument are different and give instruments their distinctive sound quality.
![Page 14: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/14.jpg)
Musical Scales• A musical scale is a sequence of
notes with certain frequencies.
MusicMusic
22
• The frequency produced by the instrument doubles after eight successive notes of the scale are played.
![Page 15: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/15.jpg)
Stringed Instruments
• Stringed instruments produce music by making strings vibrate.
MusicMusic
22
• The strings often are made of wire.
• The pitch of the note depends on the length, diameter, and tension of the string—if the string is narrower, lighter, or tighter, the pitch increases.
![Page 16: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/16.jpg)
Amplifying Vibrations• The sound produced
by a vibrating string usually is soft.
MusicMusic
22
• To amplify the sound, stringed instruments usually have a hollow chamber, or box, called a resonator, which contains air.
![Page 17: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/17.jpg)
Amplifying Vibrations
MusicMusic
22
• The resonator absorbs energy from the vibrating string and vibrates at its natural frequencies.
![Page 18: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/18.jpg)
Percussion• Percussion instruments
are struck to make a sound.
MusicMusic
22
• Striking the top surface of the drum causes it to vibrate.
• The vibrating drumhead is attached to a chamber that resonates and amplifies the sound.
![Page 19: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/19.jpg)
Drums and Pitch
• Some drums have a fixed pitch, but some can be tuned to play different notes. For example, if the drumhead on a kettledrum is tightened, the natural frequency of the drumhead is increased.
MusicMusic
22
• As a result, the pitches of the sounds produced by the kettledrum get higher.
![Page 20: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/20.jpg)
Brass and Woodwinds
• The air columns in pipes of different lengths have different natural frequencies.
MusicMusic
22
• Brass and woodwind instruments are essentially pipes or tubes of different lengths that sometimes are twisted around to make them easier to hold and carry.
![Page 21: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/21.jpg)
Brass and Woodwinds• To make music from
these instruments, the air in the pipes is made to vibrate at various frequencies.
MusicMusic
22
• A musician playing a brass instrument, such as a trumpet, makes the air column vibrate by vibrating the lips and blowing into the mouthpiece.
![Page 22: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/22.jpg)
Brass and Woodwinds
• Woodwinds such as clarinets, saxophones, and oboes contain one or two reeds in the mouthpiece that vibrate the air column when the musician blows into the mouthpiece.
MusicMusic
22
• Flutes also are woodwinds, but a flute player blows across a narrow opening to make the air column vibrate.
![Page 23: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/23.jpg)
Brass and Woodwinds• To change the note that is being played in a
woodwind instrument, a musician changes the length of the resonating column of air.
MusicMusic
22
• By making the length of the vibrating air column shorter, the pitch of sound produced is made higher.
• In a woodwind, this is done by closing and opening finger holes along the length of the instrument.
![Page 24: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/24.jpg)
Changing Pitch in Brass
• In brass instruments, musicians vary the pitch in other ways.
MusicMusic
22
• One is by blowing harder to make the air resonate at a higher natural frequency.
• Another way is by pressing valves that change the length of the tube.
![Page 25: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/25.jpg)
Beats
• Interference occurs when two valves overlap and combine to form a new wave.
MusicMusic
22
• The new wave formed by interference can have a different frequency, wavelength, and amplitude than the two original waves.
![Page 26: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/26.jpg)
Beats• Two notes close in frequency, played at the
same time, interfere to form a new sound whose loudness increases and decreases several times a second.
MusicMusic
22
• You would hear a series of beats as the sound got louder and softer.
• The beat frequency, or the number of beats you would hear each second, is equal to the difference in frequencies of the two notes.
![Page 27: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/27.jpg)
Beats Help Tune Instruments
• A piano tuner might hit a tuning fork and then the corresponding key on the piano.
MusicMusic
22
• Beats are heard when the difference in pitch is small.
• The piano string is tuned properly when the beats disappear.
![Page 28: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/28.jpg)
Reverberation• Repeated echoes of a sound are called
reverberation.
MusicMusic
22
• Some reverberation can make voices or music sound bright and lively.
• Too little reverberation makes the sound flat and lifeless.
• However, reverberation can produce a confusing mess of noise if too many sounds linger for too long.
![Page 29: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/29.jpg)
Reverberation
• Concert halls and theaters are designed to produce the appropriate level of reverberation.
MusicMusic
22
• Acoustical engineers use soft materials to reduce echoes.
• Special panels that are attached to the walls or suspended from the ceiling are designed to reflect sound toward the audience.
![Page 30: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/30.jpg)
The Ear• The ear is a complex organ that is able
to detect a wide range of sounds.
MusicMusic
22
• The ear can detect frequencies ranging from about 20Hz to about 20,000 Hz.
• The ear also can detect a wide range of sound intensities.
• The faintest sounds you can hear carry about one trillionth the amount of energy as the loudest sounds you can hear.
![Page 31: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/31.jpg)
The Ear
• The human ear has three parts—the outer ear, the middle ear, and the inner ear.
MusicMusic
22
![Page 32: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/32.jpg)
The Ear
MusicMusic
22
![Page 33: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/33.jpg)
Hearing Loss
• The ear can be damaged by disease, age, and exposure to loud sounds.
MusicMusic
22
• If damaged mammalian hair cells die, some loss of hearing results because mammals cannot make new hair cells.
• It is estimated that about 30 percent of people over 65 have some hearing loss due to aging.
![Page 34: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/34.jpg)
22Section CheckSection Check
Question 1
_______ is a group of sounds that have been deliberately produced to make a regular pattern.
A. musicB. noiseC. reverberationD. sound
![Page 35: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/35.jpg)
22Section CheckSection Check
Answer
The answer is A. Music is a form of sound.
![Page 36: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/36.jpg)
22Section CheckSection Check
Question 2
Every object, if struck, will vibrate at certain frequencies called its _______.
Answer
The answer is natural frequency. Different bells give off different pitches when struck because of their differing natural frequencies.
![Page 37: Chapter 17 Section 2 What is music? Music and noise are groups of sounds. Music is a group of sounds that have been deliberately produced to make a regular.](https://reader030.fdocuments.us/reader030/viewer/2022032805/56649ef15503460f94c02a8e/html5/thumbnails/37.jpg)
22Section CheckSection Check
Question 3
Why doesn’t a C sharp on a piano sound like a C sharp on a flute?
Answer
Though the pitch is the same, the instruments have different overtones, which cause the difference in the quality of their sounds.