Understanding Acoustics

This open access textbook, like Rayleigh’s classic Theory of Sound, focuses on experiments and on approximation techniques rather than mathematical rigor. The second edition has benefited from comments and corrections provided by many acousticians, in particular those who have used the first edition in undergraduate and graduate courses. For example, phasor notation has been added to clearly distinguish complex variables, and there is a new section on radiation from an unbaffled piston. Drawing on over 40 years of teaching experience at UCLA, the Naval Postgraduate School, and Penn State, the author presents a uniform methodology, based on hydrodynamic fundamentals for analysis of lumped-element systems and wave propagation that can accommodate dissipative mechanisms and geometrically-complex media. Five chapters on vibration and elastic waves highlight modern applications, including viscoelasticity and resonance techniques for measurement of elastic moduli, while introducing analytical techniques and approximation strategies that are revisited in nine subsequent chapters describing all aspects of generation, transmission, scattering, and reception of waves in fluids. Problems integrate multiple concepts, and several include experimental data to provide experience in choosing optimal strategies for extraction of experimental results and their uncertainties. Fundamental physical principles that do not ordinarily appear in other acoustics textbooks, like adiabatic invariance, similitude, the Kramers-Kronig relations, and the equipartition theorem, are shown to provide independent tests of results obtained from numerical solutions, commercial software, and simulations. Thanks to the Veneklasen Research Foundation, this popular textbook is now open access, making the e-book available for free download worldwide. Provides graduate-level treatment of acoustics and vibration suitable for use in courses, for self-study, and as a reference Highlights fundamental physical principles that can provide independent tests of the validity of numerical solutions, commercial software, and computer simulations Demonstrates approximation techniques that greatly simplify the mathematics without a substantial decrease in accuracy Incorporates a hydrodynamic approach to the acoustics of sound in fluids that provides a uniform methodology for analysis of lumped-element systems and wave propagation Emphasizes actual applications as examples of topics explained in the text Includes realistic end-of-chapter problems, some including experimental data, as well as a Solutions Manual for instructors. Features “Talk Like an Acoustician“ boxes to highlight key terms introduced in the text.

This textbook provides a unified approach to acoustics and vibration suitable for use in advanced undergraduate and first-year graduate courses on vibration and fluids. The book includes thorough treatment of vibration of harmonic oscillators, coupled oscillators, isotropic elasticity, and waves in solids including the use of resonance techniques for determination of elastic moduli. Drawing on 35 years of experience teaching introductory graduate acoustics at the Naval Postgraduate School and Penn State, the author presents a hydrodynamic approach to the acoustics of sound in fluids that provides a uniform methodology for analysis of lumped-element systems and wave propagation that can incorporate attenuation mechanisms and complex media. This view provides a consistent and reliable approach that can be extended with confidence to more complex fluids and future applications. Understanding Acoustics opens with a mathematical introduction that includes graphing and statistical uncertainty, followed by five chapters on vibration and elastic waves that provide important results and highlight modern applications while introducing analytical techniques that are revisited in the study of waves in fluids covered in Part II. A unified approach to waves in fluids (i.e., liquids and gases) is based on a mastery of the hydrodynamic equations. Part III demonstrates extensions of this view to nonlinear acoustics. Engaging and practical, this book is a must-read for graduate students in acoustics and vibration as well as active researchers interested in a novel approach to the material.

Understanding acoustics – the science of sound -- is essential for audio and communications engineers working in media technology. It is also extremely important for engineers to understand what allows a sound to be heard in the way it is, what makes speech intelligible, and how a particular sound is recognized within a multitude of sounds. Acoustic Signals and Hearing: A Time-Envelope and Phase Spectral Approach is unique in presenting the principles of sound and sound fields from the perspective of hearing, particularly through the use of speech and musical sounds. Acoustic Signals and Hearing: A Time-Envelope and Phase Spectral Approach is an ideal resource for researchers and acoustic engineers working in today’s environment of media technology, and graduate students studying acoustics, audio engineering, and signal processing. Presents unique sounds and sound fields from the perspective of hearing Covers source-signature and sound-path analysis Gives a reconstruction of the basics of acoustics and audio engineering via timeless topics such as linear system theory in the time and frequency domains Uses the new envelope and phase analysis approach to signal and waveform analysis Provides new perspectives via phase properties on ways to solve acoustical problems Presents straightforward mathematical formulations that give familiarity to discrete expressions of sound waves Gives a seamless and intuitive understanding — from mathematical expressions to a subjective impression of sound

This textbook provides a comprehensive description of a variety of vibration and acoustic pickups and exciters, as well as strain gauge transducers. It is an exhaustive manual for setting up basic and involved experiments in the areas of vibration, acoustics and strain measurement (using strain gauges only). It further serves as a reference to conduct experiments of a pedagogical nature in these areas. It covers the various theoretical aspects of experimental test rigs, as well as a description and choice of transducers/equipment. The fundamentals of signal processing theory, including the basics of random signals, have been included to enable the user to make a proper choice of settings on an analyser or measuring equipment. Also added is a description of modal analysis theory and related parameter extraction techniques. All chapters are provided with conceptual questions which will provoke the reader to think and gain a better understanding of the subjects. The textbook illustrates around fifty experiments in the areas of vibration, acoustics and strain measurements. Given the contents, this textbook is useful for undergraduate and postgraduate students in the areas of mechanical engineering, with applications that range from civil structures, architectural and environmental systems, and all forms of mechanical systems including transport vehicles and aircraft.

This book is an authoritative but uniquely accessible and highly illustrated guide to good acoustic design practice for architects, interior designers and acoustic professionals. It provides a user-friendly introduction to architectural acoustics and acoustics technology where the market is crowded with dense and technical texts. It will go through each typology in turn explaining the key acoustic concepts with highly illustrated and international case studies that demonstrate cutting-edge practice and technology, innovative design techniques and common challenges and solutions.

Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers and Rooms, Third Edition explains the physical and perceptual processes that are involved in sound reproduction and demonstrates how to use the processes to create high-quality listening experiences in stereo and multichannel formats. Understanding the principles of sound production is necessary to achieve the goals of sound reproduction in spaces ranging from recording control rooms and home listening rooms to large cinemas. This revision brings new science-based perspectives on the performance of loudspeakers, room acoustics, measurements and equalization, all of which need to be appropriately used to ensure the accurate delivery of music and movie sound tracks from creators to listeners. The robust website (www.routledge.com/cw/toole) is the perfect companion to this necessary resource.