The Physics of Sound (2nd Edition)

Rating:
Summary: Considerably out of date in some places
Review: Acoustics is an interesting subject, at all levels, and very important of course due to the human love for music and the need for high fidelity sound reproduction. This book is written for a readership that does not have expertise in physics or mathematics beyond the high school level. The authors do an excellent job, and the book could be used in classes on music theory or a class in physics for the humanities. The audiophile reader will gain a greater appreciation of the physics behind quality sound reproduction. Heavy use is made of demonstrations to illustrate the properties of sound, and most of these are easily set up in the classroom. I have used most of these demonstrations in the classroom, and can highly recommend their use to reinforce the understanding of the physics of sound.

The book opens, appropriately, with a discussion of simple harmonic motion, with the properties of this type of motion related to sound waves. The nature of simple harmonic motion as periodic, in contrast with noise, which is nonperiodic, is pointed out very early on. To introduce the concept of resonance, in particular the concept of coupling resonance, the author use the coupled pendulum system. This demonstration is easily constructed for classroom use and very effective in illustrating coupled resonance. Lissajous figures, which arise in the study of the relationship between two waves, is discussed in some detail.

The difference between longitudinal waves, which sound waves are, and transverse waves (such as light), is illustrated in chapter 2. To reinforce the difference between sound and light, the authors use the "bell in vacuum" demonstration. A demonstration for measuring the speed of sound is also described. Ripple tanks are used to demonstrate Huygen's principle, interference, and parabolic reflectors. The origin of beats, so important in music theory, is discussed, along with a very detailed overview of the Doppler effect. Ultrasound, very important medically, is treated also. A very brief discussion of infrasonic waves is given. Infrasonic waves, which are outside the range of hearing since they are below 20 Hz, are only experienced as vibrations. They have recently been discussed in the popular press as being explanations behind "haunted" houses. The anxiety felt in some old houses is thought of as being due to infrasonic waves.

The origin of the overtone series, so very important in music theory, is discussed in chapter 3. The three laws of Mersenne, which govern the fundamental frequency of stretched wires, are also treated. The Kundt's tube demonstration is used to describe the properties of longitudinal standing waves, and the famous Chladni plates are used to demonstrate standing waves in two dimensions. All throughout the chapter the properties of standing waves are related to music and musical instruments.

Fourier analysis and synthesis, which is typically very formidable mathematically, is presented in chapter 4 in a manner that is very understandable to the targeted readership. The Fourier synthesis of triangular, square, and sawtooth waves, along with a pulse train, is discussed. After a treatment of Fourier spectrum of these waves, the authors discuss the factors contributing to tone quality.

In chapter 5, the authors turn to more practical considerations, wherein they discuss how to create electronic music. Analog synthesizers, although very antiquated by modern standards, are used to illustrate how to combine waves to obtain special sounds or effects. The authors then immediately turn to digital synthesizers and keyboards. They discuss the Musical Instrument Digital Interface (MIDI), but the equipment they illustrate in the chapter is considerably out of date.

The anatomy and physics of the human ear and voice tract are discussed in chapter 6. The diagrams they include are useful, and they discuss the "place theory of hearing" , which is based on the correlation of sound frequency with position of response along the basilar membrane. The critical band, just noticeable difference, and the limit of frequency discrimination are all discussed in the context of this theory, with several different experiments proposed to illustrate these concepts. Most interesting is the discussion on periodicity pitch, which musicians seem to have a knack for. Also interesting is the treatment of vocal formants, which are frequency regions in which harmonics have large amplitudes. Due to the element of subjectivity in hearing and listening, the connection of the material in this chapter to "psychophysics" and "psychoacoustics" is readily apparent.

Most of the next chapter is out-dated since the authors discuss sound reproduction using LPs and tape recorders. However, the authors do discuss how this is done using compact disks, which though are themselves on their way out, due to the rise of the Internet, MP3 formats, and digital music files. Chapter 8 is timeless though, as the authors discuss the acoustics of auditoriums and rooms, detailing the most important acoustical characteristics that contribute to a pleasant musical experience, and some of the problems that arise in acoustical design. The last section of the chapter gives a fairly good overview of what is involved in setting up a home listening room.

In chapter 9, the authors take the plunge into music theory, discussing temperament and musical pitch. The history behind these concepts is detailed, emphasizing in particular that an ideal temperament is not available, its choice being dictated by the musical requirements at hand. Arithmetic descriptions of the Pythagorean, just, mean-tone, Werckmeister, and equal temperaments are given.

The last five chapters are specialized to the principles behind woodwind, brass, string, and percussion instruments, and the piano. The discussion is purely descriptive, but some of the physical principles studied in the first chapters of the book are applied here to give an understanding of the acoustical and musical properties of these instruments.

Rating:
Summary: counterbalance to the "bites my..." review
Review: Haven't read the book, but Mr. "bites my wacker" shouldn't be allowed to lower the average score.

Rating:
Summary: counterbalance to the "bites my..." review
Review: The Physics of Sound is a great book for both musicians and nonmuscians alike. Its not a book for anyone who is afraid of a little mind work. I recommend Physics of Sound because immediately upon after reading it I gained a whole new perspective and deep appreciation for the fundamental elements,and principles that govern this wonderful phenomena we call "SOUND".

Ever wondered how fast sound travel? What about how various sound frequencies react to each other,and in rooms? What exactly is sound? All these questions and more,are answered here. Physics of sound even gives you basic formulas that allow you to manipulate sound in the real world.

Gain Knowledge,Gain Insight,Gain information.