Plural Publishing produces leading academic, scientific and clinical publications in the fields of speech-language pathology, audiology, and otolaryngology.


Introduction to Sound
Acoustics for the Hearing and Speech Sciences

Fourth Edition
Charles E. Speaks
448 pages, Color Illustrations (2 Color), Hardcover, 7 x 10" 1 lbs
Included Media:
Companion Website
Release Date:


The beloved classic textbook, Introduction to Sound: Acoustics for the Hearing and Speech Sciences, is back in a new fourth edition and continues its aim to teach fundamental concepts of acoustics to students in communication sciences and disorders and related disciplines. Students in speech, language, and hearing science must have a thorough understanding of the elements of acoustics before they can successfully embark on more advanced study of both normal and disordered human communication.

The textbook is known for how acoustical concepts have been made understandable for all students, not just those who are already grounded in mathematics and physics. The book is appropriate for undergraduate courses in acoustics for speech and hearing and hearing science, as well as related courses in audiology.


  • New chapter on room acoustics (Chapter 10) summarizes relevant concepts for classrooms as well as discusses principles and methods for assessing speech intelligibility/understanding
  • Chapter 3 on acoustic impedance is now a freestanding chapter
  • Each chapter includes Practice Problems
  • Several other chapters have been reorganized to achieve an improved focus and more logical flow of concepts
  • Now includes a Glossary of key terms
  • Information has been made more concise
  • Access to a PluralPlus companion website that includes resources for both students (practice problems) and instructors (PowerPoint lecture slides and related links)
  • Availability of 17 computer animations on the web to illustrate, in slow motion, elements of acoustics that are ordinarily too fast to visualize

Preface to the First Edition
Preface to the Second Edition
Preface to the Third Edition
Preface to the Fourth Edition

Chapter 1. The Nature of Sound Waves
Properties of the Transmitting Medium
Properties of the Sound Source
Sound Source Acting on a Medium
Fundamental Physical Quantities
Derived Physical Quantities
Vibratory Motion of a Spring-Mass System
The Pendulum: An Example of Slow-Motion Vibration
Sound Wave Propagation
Types of Wave Motion
Sound Waves
Transfer of Energy
Frequently Misunderstood Concepts
Practice Problems

Chapter 2. Simple Harmonic Motion
The Waveform
The Concept of Simple Harmonic Motion
Dimensions of the Sine Wave
Frequently Misunderstood Concepts
Practice Problems

Chapter 3. Acoustic Impedance
Review of Simple Harmonic Motion
Acoustic Impedance
Practice Problems

Chapter 4. Logarithms and Antilogarithms
The Concept of Logarithms and Antilogarithms
Scales of Measurement
More on Exponents
Antilogs and Logs
Procedures for Solving Log and Antilog Problems
Practice Problems

Chapter 5. Sound Intensity and Sound Pressure: The Decibel
Absolute and Relative Measures of Acoustic Power
Sound Intensity
The Decibel
Sound Pressure
The Relation Between dB IL and dB SPL
Units of Measure for Pressure
Conversion from One Reference to Another
Combining Sound Intensities from Independent Sources
Summary of Decibels for Sound Intensity and Sound Pressure
Frequently Misunderstood Concepts
Practice Problems

Chapter 6. Complex Waves
Fourier's Theorem
Periodic Waves
Aperiodic Waves
Waveform and Spectrum
Examples of Complex Sound Waves
Measures of Sound Pressure for Complex Waves
Signal-to-Noise Ratio in dB
Frequently Misunderstood Concepts
Practice Problems

Chapter 7. Resonance and Filtering
Resonance and Filter Curves
Acoustic Impedance and Resonance
Frequency-Selective Systems: Filters
Parameters of a Filter (System Transfer Function)
Idealized Rectangular Filter
Types of Filters
Specification of Level at the Output of Filters
Another Look at Selected Types of Noise
Frequently Misunderstood Concepts
Practice Problems

Chapter 8. Distortion
Frequency Distortion
Amplitude Distortion
Transient Distortion
Practice Problems

Chapter 9. Sound Transmission
A Free, Unbounded Medium
The Inverse Square Law
Other Phenomena in Sound Transmission
Frequently Misunderstood Concepts
Practice Problems

Chapter 10. Room Acoustics
Absorption and Reflection
Room Acoustics
Speech Intelligibility: An Overview
Psychophysical/Behavioral Assessment of Speech Understanding
Physical/Predictive Assessment of Speech Understanding
The Design/Redesign Team
A Closing Comment
Practice Problems

Answers to Practice Problems
Alphabetical Listing of Selected Equations

About The Author

Charles E. Speaks

Charles E. Speaks, PhD, is a Distinguished Morse-Alumni Professor Emeritus in the Department of Speech-Language-Hearing Sciences at the University of Minnesota. He received his Bachelor of Science and Master of Arts degrees from Ohio University and his PhD degree from the University of Michigan. He taught an undergraduate/graduate-level course in acoustics at the University of Minnesota for 39 years and developed an undergraduate course on the physics and biology of spoken language. Dr. Speaks was awarded a Distinguished Teacher Award by the College of Liberal Arts in 1977 and a Horace T. Morse-Minnesota Alumni Association Award for Outstanding Contributions to Undergraduate Education in 1997, and he was inducted into the University of Minnesota Academy of Distinguished Teachers in 1999. Dr. Speaks also was awarded the Honors of the American Speech-Language-Hearing Association in 2002.

Purchasers of this book receive complimentary access to supplementary materials hosted on a PluralPlus companion website.

To access the materials, log in to the website using the URL located inside the front cover of your copy of Introduction to Sound, Fourth Edition.

To access the student materials, you must register on the companion website and log in using the access code located inside the front cover of your textbook.

To access the instructor materials, you must contact Plural Publishing, Inc. to be verified as an instructor and receive your access code.
Tel: 866-758-7251 (toll free) or 858-492-1555

Also, don't forget to utilize these 17 computer animations hosted on a separate website with no access code required.