fbpx
Wikipedia

Acoustics

Acoustics is a branch of physics that deals with the study of mechanical waves in gases, liquids, and solids including topics such as vibration, sound, ultrasound and infrasound. A scientist who works in the field of acoustics is an acoustician while someone working in the field of acoustics technology may be called an acoustical engineer. The application of acoustics is present in almost all aspects of modern society with the most obvious being the audio and noise control industries.

Lindsay's Wheel of Acoustics, which shows fields within acoustics

Hearing is one of the most crucial means of survival in the animal world and speech is one of the most distinctive characteristics of human development and culture. Accordingly, the science of acoustics spreads across many facets of human society—music, medicine, architecture, industrial production, warfare and more. Likewise, animal species such as songbirds and frogs use sound and hearing as a key element of mating rituals or for marking territories. Art, craft, science and technology have provoked one another to advance the whole, as in many other fields of knowledge. Robert Bruce Lindsay's "Wheel of Acoustics" is a well accepted overview of the various fields in acoustics.[1]

History

Etymology

The word "acoustic" is derived from the Greek word ἀκουστικός (akoustikos), meaning "of or for hearing, ready to hear"[2] and that from ἀκουστός (akoustos), "heard, audible",[3] which in turn derives from the verb ἀκούω(akouo), "I hear".[4]

The Latin synonym is "sonic", after which the term sonics used to be a synonym for acoustics[5] and later a branch of acoustics.[5] Frequencies above and below the audible range are called "ultrasonic" and "infrasonic", respectively.

Early research in acoustics

 
The fundamental and the first 6 overtones of a vibrating string. The earliest records of the study of this phenomenon are attributed to the philosopher Pythagoras in the 6th century BC.

In the 6th century BC, the ancient Greek philosopher Pythagoras wanted to know why some combinations of musical sounds seemed more beautiful than others, and he found answers in terms of numerical ratios representing the harmonic overtone series on a string. He is reputed to have observed that when the lengths of vibrating strings are expressible as ratios of integers (e.g. 2 to 3, 3 to 4), the tones produced will be harmonious, and the smaller the integers the more harmonious the sounds. For example, a string of a certain length would sound particularly harmonious with a string of twice the length (other factors being equal). In modern parlance, if a string sounds the note C when plucked, a string twice as long will sound a C an octave lower. In one system of musical tuning, the tones in between are then given by 16:9 for D, 8:5 for E, 3:2 for F, 4:3 for G, 6:5 for A, and 16:15 for B, in ascending order.[6]

Aristotle (384–322 BC) understood that sound consisted of compressions and rarefactions of air which "falls upon and strikes the air which is next to it...",[7][8] a very good expression of the nature of wave motion. On Things Heard, generally ascribed to Strato of Lampsacus, states that the pitch is related to the frequency of vibrations of the air and to the speed of sound.[9]

In about 20 BC, the Roman architect and engineer Vitruvius wrote a treatise on the acoustic properties of theaters including discussion of interference, echoes, and reverberation—the beginnings of architectural acoustics.[10] In Book V of his De architectura (The Ten Books of Architecture) Vitruvius describes sound as a wave comparable to a water wave extended to three dimensions, which, when interrupted by obstructions, would flow back and break up following waves. He described the ascending seats in ancient theaters as designed to prevent this deterioration of sound and also recommended bronze vessels of appropriate sizes be placed in theaters to resonate with the fourth, fifth and so on, up to the double octave, in order to resonate with the more desirable, harmonious notes.[11][12][13]

During the Islamic golden age, Abū Rayhān al-Bīrūnī (973-1048) is believed to have postulated that the speed of sound was much slower than the speed of light.[14][15]

 
Principles of acoustics have been applied since ancient times: a Roman theatre in the city of Amman

The physical understanding of acoustical processes advanced rapidly during and after the Scientific Revolution. Mainly Galileo Galilei (1564–1642) but also Marin Mersenne (1588–1648), independently, discovered the complete laws of vibrating strings (completing what Pythagoras and Pythagoreans had started 2000 years earlier). Galileo wrote "Waves are produced by the vibrations of a sonorous body, which spread through the air, bringing to the tympanum of the ear a stimulus which the mind interprets as sound", a remarkable statement that points to the beginnings of physiological and psychological acoustics. Experimental measurements of the speed of sound in air were carried out successfully between 1630 and 1680 by a number of investigators, prominently Mersenne. Meanwhile, Newton (1642–1727) derived the relationship for wave velocity in solids, a cornerstone of physical acoustics (Principia, 1687).

Age of Enlightenment and onward

Substantial progress in acoustics, resting on firmer mathematical and physical concepts, was made during the eighteenth century by Euler (1707–1783), Lagrange (1736–1813), and d'Alembert (1717–1783). During this era, continuum physics, or field theory, began to receive a definite mathematical structure. The wave equation emerged in a number of contexts, including the propagation of sound in air.[16]

In the nineteenth century the major figures of mathematical acoustics were Helmholtz in Germany, who consolidated the field of physiological acoustics, and Lord Rayleigh in England, who combined the previous knowledge with his own copious contributions to the field in his monumental work The Theory of Sound (1877). Also in the 19th century, Wheatstone, Ohm, and Henry developed the analogy between electricity and acoustics.

The twentieth century saw a burgeoning of technological applications of the large body of scientific knowledge that was by then in place. The first such application was Sabine's groundbreaking work in architectural acoustics, and many others followed. Underwater acoustics was used for detecting submarines in the first World War. Sound recording and the telephone played important roles in a global transformation of society. Sound measurement and analysis reached new levels of accuracy and sophistication through the use of electronics and computing. The ultrasonic frequency range enabled wholly new kinds of application in medicine and industry. New kinds of transducers (generators and receivers of acoustic energy) were invented and put to use.

Definition

 
 
At Jay Pritzker Pavilion, a LARES system is combined with a zoned sound reinforcement system, both suspended on an overhead steel trellis, to synthesize an indoor acoustic environment outdoors.

Acoustics is defined by ANSI/ASA S1.1-2013 as "(a) Science of sound, including its production, transmission, and effects, including biological and psychological effects. (b) Those qualities of a room that, together, determine its character with respect to auditory effects."

The study of acoustics revolves around the generation, propagation and reception of mechanical waves and vibrations.

 

The steps shown in the above diagram can be found in any acoustical event or process. There are many kinds of cause, both natural and volitional. There are many kinds of transduction process that convert energy from some other form into sonic energy, producing a sound wave. There is one fundamental equation that describes sound wave propagation, the acoustic wave equation, but the phenomena that emerge from it are varied and often complex. The wave carries energy throughout the propagating medium. Eventually this energy is transduced again into other forms, in ways that again may be natural and/or volitionally contrived. The final effect may be purely physical or it may reach far into the biological or volitional domains. The five basic steps are found equally well whether we are talking about an earthquake, a submarine using sonar to locate its foe, or a band playing in a rock concert.

The central stage in the acoustical process is wave propagation. This falls within the domain of physical acoustics. In fluids, sound propagates primarily as a pressure wave. In solids, mechanical waves can take many forms including longitudinal waves, transverse waves and surface waves.

Acoustics looks first at the pressure levels and frequencies in the sound wave and how the wave interacts with the environment. This interaction can be described as either a diffraction, interference or a reflection or a mix of the three. If several media are present, a refraction can also occur. Transduction processes are also of special importance to acoustics.

Fundamental concepts

Wave propagation: pressure levels

 
Spectrogram of a young girl saying "oh, no"

In fluids such as air and water, sound waves propagate as disturbances in the ambient pressure level. While this disturbance is usually small, it is still noticeable to the human ear. The smallest sound that a person can hear, known as the threshold of hearing, is nine orders of magnitude smaller than the ambient pressure. The loudness of these disturbances is related to the sound pressure level (SPL) which is measured on a logarithmic scale in decibels.

Wave propagation: frequency

Physicists and acoustic engineers tend to discuss sound pressure levels in terms of frequencies, partly because this is how our ears interpret sound. What we experience as "higher pitched" or "lower pitched" sounds are pressure vibrations having a higher or lower number of cycles per second. In a common technique of acoustic measurement, acoustic signals are sampled in time, and then presented in more meaningful forms such as octave bands or time frequency plots. Both of these popular methods are used to analyze sound and better understand the acoustic phenomenon.

The entire spectrum can be divided into three sections: audio, ultrasonic, and infrasonic. The audio range falls between 20 Hz and 20,000 Hz. This range is important because its frequencies can be detected by the human ear. This range has a number of applications, including speech communication and music. The ultrasonic range refers to the very high frequencies: 20,000 Hz and higher. This range has shorter wavelengths which allow better resolution in imaging technologies. Medical applications such as ultrasonography and elastography rely on the ultrasonic frequency range. On the other end of the spectrum, the lowest frequencies are known as the infrasonic range. These frequencies can be used to study geological phenomena such as earthquakes.

Analytic instruments such as the spectrum analyzer facilitate visualization and measurement of acoustic signals and their properties. The spectrogram produced by such an instrument is a graphical display of the time varying pressure level and frequency profiles which give a specific acoustic signal its defining character.

Transduction in acoustics

 
An inexpensive low fidelity 3.5 inch driver, typically found in small radios

A transducer is a device for converting one form of energy into another. In an electroacoustic context, this means converting sound energy into electrical energy (or vice versa). Electroacoustic transducers include loudspeakers, microphones, particle velocity sensors, hydrophones and sonar projectors. These devices convert a sound wave to or from an electric signal. The most widely used transduction principles are electromagnetism, electrostatics and piezoelectricity.

The transducers in most common loudspeakers (e.g. woofers and tweeters), are electromagnetic devices that generate waves using a suspended diaphragm driven by an electromagnetic voice coil, sending off pressure waves. Electret microphones and condenser microphones employ electrostatics—as the sound wave strikes the microphone's diaphragm, it moves and induces a voltage change. The ultrasonic systems used in medical ultrasonography employ piezoelectric transducers. These are made from special ceramics in which mechanical vibrations and electrical fields are interlinked through a property of the material itself.

Acoustician

An acoustician is an expert in the science of sound.[17]

Education

There are many types of acoustician, but they usually have a Bachelor's degree or higher qualification. Some possess a degree in acoustics, while others enter the discipline via studies in fields such as physics or engineering. Much work in acoustics requires a good grounding in Mathematics and science. Many acoustic scientists work in research and development. Some conduct basic research to advance our knowledge of the perception (e.g. hearing, psychoacoustics or neurophysiology) of speech, music and noise. Other acoustic scientists advance understanding of how sound is affected as it moves through environments, e.g. underwater acoustics, architectural acoustics or structural acoustics. Other areas of work are listed under subdisciplines below. Acoustic scientists work in government, university and private industry laboratories. Many go on to work in Acoustical Engineering. Some positions, such as Faculty (academic staff) require a Doctor of Philosophy.

Subdisciplines

Archaeoacoustics

 
St. Michael's Cave

Archaeoacoustics, also known as the archaeology of sound, is one of the only ways to experience the past with senses other than our eyes.[18] Archaeoacoustics is studied by testing the acoustic properties of prehistoric sites, including caves. Iegor Rezkinoff, a sound archaeologist, studies the acoustic properties of caves through natural sounds like humming and whistling.[19] Archaeological theories of acoustics are focused around ritualistic purposes as well as a way of echolocation in the caves. In archaeology, acoustic sounds and rituals directly correlate as specific sounds were meant to bring ritual participants closer to a spiritual awakening.[18] Parallels can also be drawn between cave wall paintings and the acoustic properties of the cave; they are both dynamic.[19] Because archaeoacoustics is a fairly new archaeological subject, acoustic sound is still being tested in these prehistoric sites today.

Aeroacoustics

Aeroacoustics is the study of noise generated by air movement, for instance via turbulence, and the movement of sound through the fluid air. This knowledge is applied in acoustical engineering to study how to quieten aircraft. Aeroacoustics is important for understanding how wind musical instruments work.[20]

Acoustic signal processing

Acoustic signal processing is the electronic manipulation of acoustic signals. Applications include: active noise control; design for hearing aids or cochlear implants; echo cancellation; music information retrieval, and perceptual coding (e.g. MP3 or Opus).[21]

Architectural acoustics

 
Symphony Hall, Boston, where auditorium acoustics began

Architectural acoustics (also known as building acoustics) involves the scientific understanding of how to achieve good sound within a building.[22] It typically involves the study of speech intelligibility, speech privacy, music quality, and vibration reduction in the built environment.[23] Commonly studied environments are hospitals, classrooms, dwellings, performance venues, recording and broadcasting studios. Focus considerations include room acoustics, airborne and impact transmission in building structures, airborne and structure-borne noise control, noise control of building systems and electroacoustic systems [1].

Bioacoustics

Bioacoustics is the scientific study of the hearing and calls of animal calls, as well as how animals are affected by the acoustic and sounds of their habitat.[24]

Electroacoustics

This subdiscipline is concerned with the recording, manipulation and reproduction of audio using electronics.[25] This might include products such as mobile phones, large scale public address systems or virtual reality systems in research laboratories.

Environmental noise and soundscapes

Environmental acoustics is concerned with noise and vibration caused by railways,[26] road traffic, aircraft, industrial equipment and recreational activities.[27] The main aim of these studies is to reduce levels of environmental noise and vibration. Research work now also has a focus on the positive use of sound in urban environments: soundscapes and tranquility.[28]

Musical acoustics

 
The primary auditory cortex, one of the main areas associated with superior pitch resolution

Musical acoustics is the study of the physics of acoustic instruments; the audio signal processing used in electronic music; the computer analysis of music and composition, and the perception and cognitive neuroscience of music.[29]

Noise

The goal this acoustics sub-discipline is to reduce the impact of unwanted sound. Scope of noise studies includes the generation, propagation, and impact on structures, objects, and people.

  • Innovative model development
  • Measurement techniques
  • Mitigation strategies
  • Inupt to the establishment of standards and regulations

Noise research investigates the impact of noise on humans and animals to include work in definitions, abatement, transportation noise, hearing protection, Jet and rocket noise, building system noise and vibration, atmospheric sound propagation, soundscapes, and low-frequency sound.

Psychoacoustics

Many studies have been conducted to identify the relationship between acoustics and cognition, or more commonly known as psychoacoustics, in which what one hears is a combination of perception and biological aspects.[30] The information intercepted by the passage of sound waves through the ear is understood and interpreted through the brain, emphasizing the connection between the mind and acoustics. Psychological changes have been seen as brain waves slow down or speed up as a result of varying auditory stimulus which can in turn affect the way one thinks, feels, or even behaves.[31] This correlation can be viewed in normal, everyday situations in which listening to an upbeat or uptempo song can cause one's foot to start tapping or a slower song can leave one feeling calm and serene. In a deeper biological look at the phenomenon of psychoacoustics, it was discovered that the central nervous system is activated by basic acoustical characteristics of music.[32] By observing how the central nervous system, which includes the brain and spine, is influenced by acoustics, the pathway in which acoustic affects the mind, and essentially the body, is evident.[32]

Speech

Acousticians study the production, processing and perception of speech. Speech recognition and Speech synthesis are two important areas of speech processing using computers. The subject also overlaps with the disciplines of physics, physiology, psychology, and linguistics.[33]

Structural Vibration and Dynamics

Structural acoustics is the study of motions and interactions of mechanical systems with their environments and the methods of their measurement, analysis, and control [2]. There are several sub-disciplines found within this regime:

Applications might include: ground vibrations from railways; vibration isolation to reduce vibration in operating theatres; studying how vibration can damage health (vibration white finger); vibration control to protect a building from earthquakes, or measuring how structure-borne sound moves through buildings.[34]

Ultrasonics

 
Ultrasound image of a fetus in the womb, viewed at 12 weeks of pregnancy (bidimensional-scan)

Ultrasonics deals with sounds at frequencies too high to be heard by humans. Specialisms include medical ultrasonics (including medical ultrasonography), sonochemistry, ultrasonic testing, material characterisation and underwater acoustics (sonar).[35]

Underwater acoustics

Underwater acoustics is the scientific study of natural and man-made sounds underwater. Applications include sonar to locate submarines, underwater communication by whales, climate change monitoring by measuring sea temperatures acoustically, sonic weapons,[36] and marine bioacoustics.[37]

Professional societies

Academic journals

See also

References

  1. ^ "What is acoustics?", Acoustical Research Group, Brigham Young University, from the original on 2021-04-16, retrieved 2021-04-16
  2. ^ Akoustikos 2020-01-23 at the Wayback Machine Henry George Liddell, Robert Scott, A Greek-English Lexicon, at Perseus
  3. ^ Akoustos 2020-01-23 at the Wayback Machine Henry George Liddell, Robert Scott, A Greek-English Lexicon, at Perseus
  4. ^ Akouo 2020-01-23 at the Wayback Machine Henry George Liddell, Robert Scott, A Greek-English Lexicon, at Perseus
  5. ^ a b Kenneth Neville Westerman (1947). Emergent Voice. C. F. Westerman. from the original on 2023-03-01. Retrieved 2016-02-28.
  6. ^ C. Boyer and U. Merzbach. A History of Mathematics. Wiley 1991, p. 55.
  7. ^ "How Sound Propagates" (PDF). Princeton University Press. Archived (PDF) from the original on 2022-10-09. Retrieved 9 February 2016. (quoting from Aristotle's Treatise on Sound and Hearing)
  8. ^ Whewell, William, 1794-1866. History of the inductive sciences : from the earliest to the present times. Volume 2. Cambridge. p. 295. ISBN 978-0-511-73434-2. OCLC 889953932.{{cite book}}: CS1 maint: multiple names: authors list (link)
  9. ^ Greek musical writings. Barker, Andrew (1st pbk. ed.). Cambridge: Cambridge University Press. 2004. p. 98. ISBN 0-521-38911-9. OCLC 63122899.{{cite book}}: CS1 maint: others (link)
  10. ^ ACOUSTICS, Bruce Lindsay, Dowden – Hutchingon Books Publishers, Chapter 3
  11. ^ Vitruvius Pollio, Vitruvius, the Ten Books on Architecture (1914) Tr. Morris Hickey Morgan BookV, Sec.6–8
  12. ^ Vitruvius article @Wikiquote
  13. ^ Ernst Mach, Introduction to The Science of Mechanics: A Critical and Historical Account of its Development (1893, 1960) Tr. Thomas J. McCormack
  14. ^ Sparavigna, Amelia Carolina (December 2013). "The Science of Al-Biruni" (PDF). International Journal of Sciences. 2 (12): 52–60. arXiv:1312.7288. Bibcode:2013arXiv1312.7288S. doi:10.18483/ijSci.364. S2CID 119230163. (PDF) from the original on 2018-07-21. Retrieved 2018-11-04.
  15. ^ . School of Mathematics and Statistics, University of St. Andrews, Scotland. November 1999. Archived from the original on 2016-11-21. Retrieved 2018-08-20.
  16. ^ Pierce, Allan D. (1989). Acoustics : an introduction to its physical principles and applications (1989 ed.). Woodbury, N.Y.: Acoustical Society of America. ISBN 0-88318-612-8. OCLC 21197318.
  17. ^ Schwarz, C (1991). Chambers concise dictionary.
  18. ^ a b Clemens, Martin J. (2016-01-31). "Archaeoacoustics: Listening to the Sounds of History". The Daily Grail. from the original on 2019-04-13. Retrieved 2019-04-13.
  19. ^ a b Jacobs, Emma (2017-04-13). "With Archaeoacoustics, Researchers Listen for Clues to the Prehistoric Past". Atlas Obscura. from the original on 2019-04-13. Retrieved 2019-04-13.
  20. ^ da Silva, Andrey Ricardo (2009). Aeroacoustics of Wind Instruments: Investigations and Numerical Methods. VDM Verlag. ISBN 978-3639210644.
  21. ^ Slaney, Malcolm; Patrick A. Naylor (2011). "Trends in Audio and Acoustic Signal Processing". ICASSP.
  22. ^ Morfey, Christopher (2001). Dictionary of Acoustics. Academic Press. p. 32.
  23. ^ Templeton, Duncan (1993). Acoustics in the Built Environment: Advice for the Design Team. Architectural Press. ISBN 978-0750605380.
  24. ^ "Bioacoustics - the International Journal of Animal Sound and its Recording". Taylor & Francis. from the original on 5 September 2012. Retrieved 31 July 2012.
  25. ^ Acoustical Society of America. . Archived from the original on 2015-09-04. Retrieved 21 May 2013.
  26. ^ Krylov, V.V., ed. (2001). Noise and Vibration from High-speed Trains. Thomas Telford. ISBN 9780727729637.
  27. ^ World Health Organisation (2011). Burden of disease from environmental noise (PDF). WHO. ISBN 978-92-890-0229-5. Archived (PDF) from the original on 2022-10-09.
  28. ^ Kang, Jian (2006). Urban Sound Environment. CRC Press. ISBN 978-0415358576.
  29. ^ Technical Committee on Musical Acoustics (TCMU) of the Acoustical Society of America (ASA). . Archived from the original on 2001-06-13. Retrieved 22 May 2013.
  30. ^ Iakovides, Stefanos A.; Iliadou, Vassiliki TH; Bizeli, Vassiliki TH; Kaprinis, Stergios G.; Fountoulakis, Konstantinos N.; Kaprinis, George S. (2004-03-29). "Psychophysiology and psychoacoustics of music: Perception of complex sound in normal subjects and psychiatric patients". Annals of General Hospital Psychiatry. 3 (1): 6. doi:10.1186/1475-2832-3-6. ISSN 1475-2832. PMC 400748. PMID 15050030.
  31. ^ "Psychoacoustics: The Power of Sound". Memtech Acoustical. 2016-02-11. from the original on 2019-04-15. Retrieved 2019-04-14.
  32. ^ a b Green, David M. (1960). "Psychoacoustics and Detection Theory". The Journal of the Acoustical Society of America. 32 (10): 1189–1203. Bibcode:1960ASAJ...32.1189G. doi:10.1121/1.1907882. ISSN 0001-4966.
  33. ^ "Technical Committee on Speech Communication". Acoustical Society of America. from the original on 2018-11-05. Retrieved 2018-11-04.
  34. ^ "Structural Acoustics & Vibration Technical Committee". from the original on 10 August 2018.
  35. ^ Ensminger, Dale (2012). Ultrasonics: Fundamentals, Technologies, and Applications. CRC Press. pp. 1–2.
  36. ^ D. Lohse, B. Schmitz & M. Versluis (2001). "Snapping shrimp make flashing bubbles". Nature. 413 (6855): 477–478. Bibcode:2001Natur.413..477L. doi:10.1038/35097152. PMID 11586346. S2CID 4429684.
  37. ^ ASA Underwater Acoustics Technical Committee. . Archived from the original on 30 July 2013. Retrieved 22 May 2013.

Further reading

  • Attenborough K, Postema M (2008). A pocket-sized introduction to acoustics. Kingston upon Hull: University of Hull. doi:10.5281/zenodo.7504060. ISBN 978-90-812588-2-1.
  • Benade AH (1976). Fundamentals of Musical Acoustics. New York: Oxford University Press. ISBN 978-0-19-502030-4. OCLC 2270137.
  • Biryukov SV, Gulyaev YV, Krylov VV, Plessky VP (1995). Surface Acoustic Waves in Inhomogeneous Media. Heidelberg: Springer. ISBN 978-3-540-58460-5.
  • Crocker MJ, ed. (1997). Encyclopedia of Acoustics. Hoboken: Wiley. OCLC 441305164.
  • Falkovich G (2011). Fluid Mechanics, a short course for physicists. Cambridge: Cambridge University Press. ISBN 978-1-107-00575-4.
  • Fahy FJ, Gardonio P (2007). Sound and Structural Vibration: Radiation, Transmission and Response (2nd ed.). Amsterdam: Academic Press. ISBN 978-0-08-047110-5.
  • Junger MC, Feit D (1986). (2nd ed.). Cambridge: MIT Press. Archived from the original on 2014-06-05.
  • Kinsler LE (1999). Fundamentals of Acoustics (4th ed.). Hoboken: Wiley. ISBN 978-04718-4-789-2.
  • Mason WP, Thurston RN (1981). . Heidelberg: Springer. Archived from the original on 2013-12-25.
  • Morse PM, Ingard KU (1986). Theoretical Acoustics. Princeton: Princeton University Press. ISBN 0-691-08425-4.
  • Pierce AD (1989). Acoustics: An Introduction to its Physical Principles and Applications. Melville: Acoustical Society of America. ISBN 0-88318-612-8.
  • Raichel DR (2006). The Science and Applications of Acoustics (2nd ed.). Heidelberg: Springer. ISBN 0-387-30089-9.
  • Lord Rayleigh (1894). The Theory of Sound. New York: Dover. ISBN 978-0-8446-3028-1.
  • Skudrzyk E (1971). The Foundations of Acoustics: Basic Mathematics and Basic Acoustics. Heidelberg: Springer.
  • Stephens RW, Bate AE (1966). Acoustics and Vibrational Physics (2nd ed.). London: Edward Arnold.
  • Wilson CE (2006). Noise Control (Revised ed.). Malabar: Krieger. ISBN 978-1-57524-237-8. OCLC 59223706.

External links

  • International Commission for Acoustics
  • European Acoustics Association
  • Acoustical Society of America
  • Institute of Noise Control Engineers
  • National Council of Acoustical Consultants
  • Institute of Acoustic in UK
  • Australian Acoustical Society (AAS)

acoustics, other, uses, disambiguation, branch, physics, that, deals, with, study, mechanical, waves, gases, liquids, solids, including, topics, such, vibration, sound, ultrasound, infrasound, scientist, works, field, acoustics, acoustician, while, someone, wo. For other uses see Acoustics disambiguation Acoustics is a branch of physics that deals with the study of mechanical waves in gases liquids and solids including topics such as vibration sound ultrasound and infrasound A scientist who works in the field of acoustics is an acoustician while someone working in the field of acoustics technology may be called an acoustical engineer The application of acoustics is present in almost all aspects of modern society with the most obvious being the audio and noise control industries Lindsay s Wheel of Acoustics which shows fields within acoustics Hearing is one of the most crucial means of survival in the animal world and speech is one of the most distinctive characteristics of human development and culture Accordingly the science of acoustics spreads across many facets of human society music medicine architecture industrial production warfare and more Likewise animal species such as songbirds and frogs use sound and hearing as a key element of mating rituals or for marking territories Art craft science and technology have provoked one another to advance the whole as in many other fields of knowledge Robert Bruce Lindsay s Wheel of Acoustics is a well accepted overview of the various fields in acoustics 1 Contents 1 History 1 1 Etymology 1 2 Early research in acoustics 1 3 Age of Enlightenment and onward 2 Definition 3 Fundamental concepts 3 1 Wave propagation pressure levels 3 2 Wave propagation frequency 3 3 Transduction in acoustics 4 Acoustician 4 1 Education 5 Subdisciplines 5 1 Archaeoacoustics 5 2 Aeroacoustics 5 3 Acoustic signal processing 5 4 Architectural acoustics 5 5 Bioacoustics 5 6 Electroacoustics 5 7 Environmental noise and soundscapes 5 8 Musical acoustics 5 9 Noise 5 10 Psychoacoustics 5 11 Speech 5 12 Structural Vibration and Dynamics 5 13 Ultrasonics 5 14 Underwater acoustics 6 Professional societies 7 Academic journals 8 See also 9 References 10 Further reading 11 External linksHistory EditEtymology Edit The word acoustic is derived from the Greek word ἀkoystikos akoustikos meaning of or for hearing ready to hear 2 and that from ἀkoystos akoustos heard audible 3 which in turn derives from the verb ἀkoyw akouo I hear 4 The Latin synonym is sonic after which the term sonics used to be a synonym for acoustics 5 and later a branch of acoustics 5 Frequencies above and below the audible range are called ultrasonic and infrasonic respectively Early research in acoustics Edit The fundamental and the first 6 overtones of a vibrating string The earliest records of the study of this phenomenon are attributed to the philosopher Pythagoras in the 6th century BC In the 6th century BC the ancient Greek philosopher Pythagoras wanted to know why some combinations of musical sounds seemed more beautiful than others and he found answers in terms of numerical ratios representing the harmonic overtone series on a string He is reputed to have observed that when the lengths of vibrating strings are expressible as ratios of integers e g 2 to 3 3 to 4 the tones produced will be harmonious and the smaller the integers the more harmonious the sounds For example a string of a certain length would sound particularly harmonious with a string of twice the length other factors being equal In modern parlance if a string sounds the note C when plucked a string twice as long will sound a C an octave lower In one system of musical tuning the tones in between are then given by 16 9 for D 8 5 for E 3 2 for F 4 3 for G 6 5 for A and 16 15 for B in ascending order 6 Aristotle 384 322 BC understood that sound consisted of compressions and rarefactions of air which falls upon and strikes the air which is next to it 7 8 a very good expression of the nature of wave motion On Things Heard generally ascribed to Strato of Lampsacus states that the pitch is related to the frequency of vibrations of the air and to the speed of sound 9 In about 20 BC the Roman architect and engineer Vitruvius wrote a treatise on the acoustic properties of theaters including discussion of interference echoes and reverberation the beginnings of architectural acoustics 10 In Book V of his De architectura The Ten Books of Architecture Vitruvius describes sound as a wave comparable to a water wave extended to three dimensions which when interrupted by obstructions would flow back and break up following waves He described the ascending seats in ancient theaters as designed to prevent this deterioration of sound and also recommended bronze vessels of appropriate sizes be placed in theaters to resonate with the fourth fifth and so on up to the double octave in order to resonate with the more desirable harmonious notes 11 12 13 During the Islamic golden age Abu Rayhan al Biruni 973 1048 is believed to have postulated that the speed of sound was much slower than the speed of light 14 15 Principles of acoustics have been applied since ancient times a Roman theatre in the city of Amman The physical understanding of acoustical processes advanced rapidly during and after the Scientific Revolution Mainly Galileo Galilei 1564 1642 but also Marin Mersenne 1588 1648 independently discovered the complete laws of vibrating strings completing what Pythagoras and Pythagoreans had started 2000 years earlier Galileo wrote Waves are produced by the vibrations of a sonorous body which spread through the air bringing to the tympanum of the ear a stimulus which the mind interprets as sound a remarkable statement that points to the beginnings of physiological and psychological acoustics Experimental measurements of the speed of sound in air were carried out successfully between 1630 and 1680 by a number of investigators prominently Mersenne Meanwhile Newton 1642 1727 derived the relationship for wave velocity in solids a cornerstone of physical acoustics Principia 1687 Age of Enlightenment and onward Edit Substantial progress in acoustics resting on firmer mathematical and physical concepts was made during the eighteenth century by Euler 1707 1783 Lagrange 1736 1813 and d Alembert 1717 1783 During this era continuum physics or field theory began to receive a definite mathematical structure The wave equation emerged in a number of contexts including the propagation of sound in air 16 In the nineteenth century the major figures of mathematical acoustics were Helmholtz in Germany who consolidated the field of physiological acoustics and Lord Rayleigh in England who combined the previous knowledge with his own copious contributions to the field in his monumental work The Theory of Sound 1877 Also in the 19th century Wheatstone Ohm and Henry developed the analogy between electricity and acoustics The twentieth century saw a burgeoning of technological applications of the large body of scientific knowledge that was by then in place The first such application was Sabine s groundbreaking work in architectural acoustics and many others followed Underwater acoustics was used for detecting submarines in the first World War Sound recording and the telephone played important roles in a global transformation of society Sound measurement and analysis reached new levels of accuracy and sophistication through the use of electronics and computing The ultrasonic frequency range enabled wholly new kinds of application in medicine and industry New kinds of transducers generators and receivers of acoustic energy were invented and put to use Definition EditJay Pritzker Pavilion At Jay Pritzker Pavilion a LARES system is combined with a zoned sound reinforcement system both suspended on an overhead steel trellis to synthesize an indoor acoustic environment outdoors Acoustics is defined by ANSI ASA S1 1 2013 as a Science of sound including its production transmission and effects including biological and psychological effects b Those qualities of a room that together determine its character with respect to auditory effects The study of acoustics revolves around the generation propagation and reception of mechanical waves and vibrations dd The steps shown in the above diagram can be found in any acoustical event or process There are many kinds of cause both natural and volitional There are many kinds of transduction process that convert energy from some other form into sonic energy producing a sound wave There is one fundamental equation that describes sound wave propagation the acoustic wave equation but the phenomena that emerge from it are varied and often complex The wave carries energy throughout the propagating medium Eventually this energy is transduced again into other forms in ways that again may be natural and or volitionally contrived The final effect may be purely physical or it may reach far into the biological or volitional domains The five basic steps are found equally well whether we are talking about an earthquake a submarine using sonar to locate its foe or a band playing in a rock concert The central stage in the acoustical process is wave propagation This falls within the domain of physical acoustics In fluids sound propagates primarily as a pressure wave In solids mechanical waves can take many forms including longitudinal waves transverse waves and surface waves Acoustics looks first at the pressure levels and frequencies in the sound wave and how the wave interacts with the environment This interaction can be described as either a diffraction interference or a reflection or a mix of the three If several media are present a refraction can also occur Transduction processes are also of special importance to acoustics Fundamental concepts EditWave propagation pressure levels Edit Main article Sound pressure Spectrogram of a young girl saying oh no In fluids such as air and water sound waves propagate as disturbances in the ambient pressure level While this disturbance is usually small it is still noticeable to the human ear The smallest sound that a person can hear known as the threshold of hearing is nine orders of magnitude smaller than the ambient pressure The loudness of these disturbances is related to the sound pressure level SPL which is measured on a logarithmic scale in decibels Wave propagation frequency Edit Further information Sound Frequency Physicists and acoustic engineers tend to discuss sound pressure levels in terms of frequencies partly because this is how our ears interpret sound What we experience as higher pitched or lower pitched sounds are pressure vibrations having a higher or lower number of cycles per second In a common technique of acoustic measurement acoustic signals are sampled in time and then presented in more meaningful forms such as octave bands or time frequency plots Both of these popular methods are used to analyze sound and better understand the acoustic phenomenon The entire spectrum can be divided into three sections audio ultrasonic and infrasonic The audio range falls between 20 Hz and 20 000 Hz This range is important because its frequencies can be detected by the human ear This range has a number of applications including speech communication and music The ultrasonic range refers to the very high frequencies 20 000 Hz and higher This range has shorter wavelengths which allow better resolution in imaging technologies Medical applications such as ultrasonography and elastography rely on the ultrasonic frequency range On the other end of the spectrum the lowest frequencies are known as the infrasonic range These frequencies can be used to study geological phenomena such as earthquakes Analytic instruments such as the spectrum analyzer facilitate visualization and measurement of acoustic signals and their properties The spectrogram produced by such an instrument is a graphical display of the time varying pressure level and frequency profiles which give a specific acoustic signal its defining character Transduction in acoustics Edit An inexpensive low fidelity 3 5 inch driver typically found in small radios A transducer is a device for converting one form of energy into another In an electroacoustic context this means converting sound energy into electrical energy or vice versa Electroacoustic transducers include loudspeakers microphones particle velocity sensors hydrophones and sonar projectors These devices convert a sound wave to or from an electric signal The most widely used transduction principles are electromagnetism electrostatics and piezoelectricity The transducers in most common loudspeakers e g woofers and tweeters are electromagnetic devices that generate waves using a suspended diaphragm driven by an electromagnetic voice coil sending off pressure waves Electret microphones and condenser microphones employ electrostatics as the sound wave strikes the microphone s diaphragm it moves and induces a voltage change The ultrasonic systems used in medical ultrasonography employ piezoelectric transducers These are made from special ceramics in which mechanical vibrations and electrical fields are interlinked through a property of the material itself Acoustician EditAn acoustician is an expert in the science of sound 17 Education Edit There are many types of acoustician but they usually have a Bachelor s degree or higher qualification Some possess a degree in acoustics while others enter the discipline via studies in fields such as physics or engineering Much work in acoustics requires a good grounding in Mathematics and science Many acoustic scientists work in research and development Some conduct basic research to advance our knowledge of the perception e g hearing psychoacoustics or neurophysiology of speech music and noise Other acoustic scientists advance understanding of how sound is affected as it moves through environments e g underwater acoustics architectural acoustics or structural acoustics Other areas of work are listed under subdisciplines below Acoustic scientists work in government university and private industry laboratories Many go on to work in Acoustical Engineering Some positions such as Faculty academic staff require a Doctor of Philosophy Subdisciplines EditArchaeoacoustics Edit St Michael s Cave Archaeoacoustics also known as the archaeology of sound is one of the only ways to experience the past with senses other than our eyes 18 Archaeoacoustics is studied by testing the acoustic properties of prehistoric sites including caves Iegor Rezkinoff a sound archaeologist studies the acoustic properties of caves through natural sounds like humming and whistling 19 Archaeological theories of acoustics are focused around ritualistic purposes as well as a way of echolocation in the caves In archaeology acoustic sounds and rituals directly correlate as specific sounds were meant to bring ritual participants closer to a spiritual awakening 18 Parallels can also be drawn between cave wall paintings and the acoustic properties of the cave they are both dynamic 19 Because archaeoacoustics is a fairly new archaeological subject acoustic sound is still being tested in these prehistoric sites today Aeroacoustics Edit Main article Aeroacoustics Aeroacoustics is the study of noise generated by air movement for instance via turbulence and the movement of sound through the fluid air This knowledge is applied in acoustical engineering to study how to quieten aircraft Aeroacoustics is important for understanding how wind musical instruments work 20 Acoustic signal processing Edit See also Audio signal processing Acoustic signal processing is the electronic manipulation of acoustic signals Applications include active noise control design for hearing aids or cochlear implants echo cancellation music information retrieval and perceptual coding e g MP3 or Opus 21 Architectural acoustics Edit Main article Architectural acoustics Symphony Hall Boston where auditorium acoustics began Architectural acoustics also known as building acoustics involves the scientific understanding of how to achieve good sound within a building 22 It typically involves the study of speech intelligibility speech privacy music quality and vibration reduction in the built environment 23 Commonly studied environments are hospitals classrooms dwellings performance venues recording and broadcasting studios Focus considerations include room acoustics airborne and impact transmission in building structures airborne and structure borne noise control noise control of building systems and electroacoustic systems 1 Bioacoustics Edit Main article Bioacoustics Bioacoustics is the scientific study of the hearing and calls of animal calls as well as how animals are affected by the acoustic and sounds of their habitat 24 Electroacoustics Edit See also Audio Engineering and Sound reinforcement system This subdiscipline is concerned with the recording manipulation and reproduction of audio using electronics 25 This might include products such as mobile phones large scale public address systems or virtual reality systems in research laboratories Environmental noise and soundscapes Edit Main article Environmental noise See also Noise pollution and Noise control Environmental acoustics is concerned with noise and vibration caused by railways 26 road traffic aircraft industrial equipment and recreational activities 27 The main aim of these studies is to reduce levels of environmental noise and vibration Research work now also has a focus on the positive use of sound in urban environments soundscapes and tranquility 28 Musical acoustics Edit Main article Musical acoustics The primary auditory cortex one of the main areas associated with superior pitch resolution Musical acoustics is the study of the physics of acoustic instruments the audio signal processing used in electronic music the computer analysis of music and composition and the perception and cognitive neuroscience of music 29 Noise Edit The goal this acoustics sub discipline is to reduce the impact of unwanted sound Scope of noise studies includes the generation propagation and impact on structures objects and people Innovative model development Measurement techniques Mitigation strategies Inupt to the establishment of standards and regulationsNoise research investigates the impact of noise on humans and animals to include work in definitions abatement transportation noise hearing protection Jet and rocket noise building system noise and vibration atmospheric sound propagation soundscapes and low frequency sound Psychoacoustics Edit Many studies have been conducted to identify the relationship between acoustics and cognition or more commonly known as psychoacoustics in which what one hears is a combination of perception and biological aspects 30 The information intercepted by the passage of sound waves through the ear is understood and interpreted through the brain emphasizing the connection between the mind and acoustics Psychological changes have been seen as brain waves slow down or speed up as a result of varying auditory stimulus which can in turn affect the way one thinks feels or even behaves 31 This correlation can be viewed in normal everyday situations in which listening to an upbeat or uptempo song can cause one s foot to start tapping or a slower song can leave one feeling calm and serene In a deeper biological look at the phenomenon of psychoacoustics it was discovered that the central nervous system is activated by basic acoustical characteristics of music 32 By observing how the central nervous system which includes the brain and spine is influenced by acoustics the pathway in which acoustic affects the mind and essentially the body is evident 32 Speech Edit Main article Speech Acousticians study the production processing and perception of speech Speech recognition and Speech synthesis are two important areas of speech processing using computers The subject also overlaps with the disciplines of physics physiology psychology and linguistics 33 Structural Vibration and Dynamics Edit Main article Vibration Structural acoustics is the study of motions and interactions of mechanical systems with their environments and the methods of their measurement analysis and control 2 There are several sub disciplines found within this regime Modal Analysis Material characterization Structural health monitoring Acoustic Metamaterials Friction AcousticsApplications might include ground vibrations from railways vibration isolation to reduce vibration in operating theatres studying how vibration can damage health vibration white finger vibration control to protect a building from earthquakes or measuring how structure borne sound moves through buildings 34 Ultrasonics Edit Ultrasound image of a fetus in the womb viewed at 12 weeks of pregnancy bidimensional scan Main article Ultrasound Ultrasonics deals with sounds at frequencies too high to be heard by humans Specialisms include medical ultrasonics including medical ultrasonography sonochemistry ultrasonic testing material characterisation and underwater acoustics sonar 35 Underwater acoustics Edit Main article Underwater acoustics Underwater acoustics is the scientific study of natural and man made sounds underwater Applications include sonar to locate submarines underwater communication by whales climate change monitoring by measuring sea temperatures acoustically sonic weapons 36 and marine bioacoustics 37 Professional societies EditThe Acoustical Society of America ASA Australian Acoustical Society AAS The European Acoustics Association EAA Institute of Electrical and Electronics Engineers IEEE Institute of Acoustics IoA UK The Audio Engineering Society AES American Society of Mechanical Engineers Noise Control and Acoustics Division ASME NCAD International Commission for Acoustics ICA American Institute of Aeronautics and Astronautics Aeroacoustics AIAA International Computer Music Association ICMA Academic journals EditMain category Acoustics journals Acta Acustica united with Acustica Applied Acoustics IEEE Transacions on Ultrasonics Ferroelectrics and Frequency Control Journal of the Acoustical Society of America JASA Journal of the Acoustical Society of America Express Letters JASA EL Journal of the Audio Engineering Society Journal of Sound and Vibration JSV Journal of Vibration and Acoustics American Society of Mechanical Engineers MDPI Acoustics Ultrasonics journal Ultrasonics SonochemistrySee also EditOutline of acoustics Acoustic attenuation Acoustic emission Acoustic engineering Acoustic impedance Acoustic levitation Acoustic location Acoustic phonetics Acoustic streaming Acoustic tags Acoustic thermometry Acoustic wave Audiology Auditory illusion Diffraction Doppler effect Fisheries acoustics Friction acoustics Helioseismology Lamb wave Linear elasticity The Little Red Book of Acoustics in the UK Longitudinal wave Musicology Music therapy Noise pollution One Way Wave Equation Phonon Picosecond ultrasonics Rayleigh wave Shock wave Seismology Sonification Sonochemistry Soundproofing Soundscape Sonic boom Sonoluminescence Surface acoustic wave Thermoacoustics Transverse wave Wave equationReferences Edit What is acoustics Acoustical Research Group Brigham Young University archived from the original on 2021 04 16 retrieved 2021 04 16 Akoustikos Archived 2020 01 23 at the Wayback Machine Henry George Liddell Robert Scott A Greek English Lexicon at Perseus Akoustos Archived 2020 01 23 at the Wayback Machine Henry George Liddell Robert Scott A Greek English Lexicon at Perseus Akouo Archived 2020 01 23 at the Wayback Machine Henry George Liddell Robert Scott A Greek English Lexicon at Perseus a b Kenneth Neville Westerman 1947 Emergent Voice C F Westerman Archived from the original on 2023 03 01 Retrieved 2016 02 28 C Boyer and U Merzbach A History of Mathematics Wiley 1991 p 55 How Sound Propagates PDF Princeton University Press Archived PDF from the original on 2022 10 09 Retrieved 9 February 2016 quoting from Aristotle s Treatise on Sound and Hearing Whewell William 1794 1866 History of the inductive sciences from the earliest to the present times Volume 2 Cambridge p 295 ISBN 978 0 511 73434 2 OCLC 889953932 a href Template Cite book html title Template Cite book cite book a CS1 maint multiple names authors list link Greek musical writings Barker Andrew 1st pbk ed Cambridge Cambridge University Press 2004 p 98 ISBN 0 521 38911 9 OCLC 63122899 a href Template Cite book html title Template Cite book cite book a CS1 maint others link ACOUSTICS Bruce Lindsay Dowden Hutchingon Books Publishers Chapter 3 Vitruvius Pollio Vitruvius the Ten Books on Architecture 1914 Tr Morris Hickey Morgan BookV Sec 6 8 Vitruvius article Wikiquote Ernst Mach Introduction to The Science of Mechanics A Critical and Historical Account of its Development 1893 1960 Tr Thomas J McCormack Sparavigna Amelia Carolina December 2013 The Science of Al Biruni PDF International Journal of Sciences 2 12 52 60 arXiv 1312 7288 Bibcode 2013arXiv1312 7288S doi 10 18483 ijSci 364 S2CID 119230163 Archived PDF from the original on 2018 07 21 Retrieved 2018 11 04 Abu Arrayhan Muhammad ibn Ahmad al Biruni School of Mathematics and Statistics University of St Andrews Scotland November 1999 Archived from the original on 2016 11 21 Retrieved 2018 08 20 Pierce Allan D 1989 Acoustics an introduction to its physical principles and applications 1989 ed Woodbury N Y Acoustical Society of America ISBN 0 88318 612 8 OCLC 21197318 Schwarz C 1991 Chambers concise dictionary a b Clemens Martin J 2016 01 31 Archaeoacoustics Listening to the Sounds of History The Daily Grail Archived from the original on 2019 04 13 Retrieved 2019 04 13 a b Jacobs Emma 2017 04 13 With Archaeoacoustics Researchers Listen for Clues to the Prehistoric Past Atlas Obscura Archived from the original on 2019 04 13 Retrieved 2019 04 13 da Silva Andrey Ricardo 2009 Aeroacoustics of Wind Instruments Investigations and Numerical Methods VDM Verlag ISBN 978 3639210644 Slaney Malcolm Patrick A Naylor 2011 Trends in Audio and Acoustic Signal Processing ICASSP Morfey Christopher 2001 Dictionary of Acoustics Academic Press p 32 Templeton Duncan 1993 Acoustics in the Built Environment Advice for the Design Team Architectural Press ISBN 978 0750605380 Bioacoustics the International Journal of Animal Sound and its Recording Taylor amp Francis Archived from the original on 5 September 2012 Retrieved 31 July 2012 Acoustical Society of America Acoustics and You A Career in Acoustics Archived from the original on 2015 09 04 Retrieved 21 May 2013 Krylov V V ed 2001 Noise and Vibration from High speed Trains Thomas Telford ISBN 9780727729637 World Health Organisation 2011 Burden of disease from environmental noise PDF WHO ISBN 978 92 890 0229 5 Archived PDF from the original on 2022 10 09 Kang Jian 2006 Urban Sound Environment CRC Press ISBN 978 0415358576 Technical Committee on Musical Acoustics TCMU of the Acoustical Society of America ASA ASA TCMU Home Page Archived from the original on 2001 06 13 Retrieved 22 May 2013 Iakovides Stefanos A Iliadou Vassiliki TH Bizeli Vassiliki TH Kaprinis Stergios G Fountoulakis Konstantinos N Kaprinis George S 2004 03 29 Psychophysiology and psychoacoustics of music Perception of complex sound in normal subjects and psychiatric patients Annals of General Hospital Psychiatry 3 1 6 doi 10 1186 1475 2832 3 6 ISSN 1475 2832 PMC 400748 PMID 15050030 Psychoacoustics The Power of Sound Memtech Acoustical 2016 02 11 Archived from the original on 2019 04 15 Retrieved 2019 04 14 a b Green David M 1960 Psychoacoustics and Detection Theory The Journal of the Acoustical Society of America 32 10 1189 1203 Bibcode 1960ASAJ 32 1189G doi 10 1121 1 1907882 ISSN 0001 4966 Technical Committee on Speech Communication Acoustical Society of America Archived from the original on 2018 11 05 Retrieved 2018 11 04 Structural Acoustics amp Vibration Technical Committee Archived from the original on 10 August 2018 Ensminger Dale 2012 Ultrasonics Fundamentals Technologies and Applications CRC Press pp 1 2 D Lohse B Schmitz amp M Versluis 2001 Snapping shrimp make flashing bubbles Nature 413 6855 477 478 Bibcode 2001Natur 413 477L doi 10 1038 35097152 PMID 11586346 S2CID 4429684 ASA Underwater Acoustics Technical Committee Underwater Acoustics Archived from the original on 30 July 2013 Retrieved 22 May 2013 Further reading EditAttenborough K Postema M 2008 A pocket sized introduction to acoustics Kingston upon Hull University of Hull doi 10 5281 zenodo 7504060 ISBN 978 90 812588 2 1 Benade AH 1976 Fundamentals of Musical Acoustics New York Oxford University Press ISBN 978 0 19 502030 4 OCLC 2270137 Biryukov SV Gulyaev YV Krylov VV Plessky VP 1995 Surface Acoustic Waves in Inhomogeneous Media Heidelberg Springer ISBN 978 3 540 58460 5 Crocker MJ ed 1997 Encyclopedia of Acoustics Hoboken Wiley OCLC 441305164 Falkovich G 2011 Fluid Mechanics a short course for physicists Cambridge Cambridge University Press ISBN 978 1 107 00575 4 Fahy FJ Gardonio P 2007 Sound and Structural Vibration Radiation Transmission and Response 2nd ed Amsterdam Academic Press ISBN 978 0 08 047110 5 Junger MC Feit D 1986 Sound Structures and Their Interaction 2nd ed Cambridge MIT Press Archived from the original on 2014 06 05 Kinsler LE 1999 Fundamentals of Acoustics 4th ed Hoboken Wiley ISBN 978 04718 4 789 2 Mason WP Thurston RN 1981 Physical Acoustics Heidelberg Springer Archived from the original on 2013 12 25 Morse PM Ingard KU 1986 Theoretical Acoustics Princeton Princeton University Press ISBN 0 691 08425 4 Pierce AD 1989 Acoustics An Introduction to its Physical Principles and Applications Melville Acoustical Society of America ISBN 0 88318 612 8 Raichel DR 2006 The Science and Applications of Acoustics 2nd ed Heidelberg Springer ISBN 0 387 30089 9 Lord Rayleigh 1894 The Theory of Sound New York Dover ISBN 978 0 8446 3028 1 Skudrzyk E 1971 The Foundations of Acoustics Basic Mathematics and Basic Acoustics Heidelberg Springer Stephens RW Bate AE 1966 Acoustics and Vibrational Physics 2nd ed London Edward Arnold Wilson CE 2006 Noise Control Revised ed Malabar Krieger ISBN 978 1 57524 237 8 OCLC 59223706 External links Edit Wikimedia Commons has media related to Acoustics Wikisource has original text related to this article Acoustics Wikibooks has a book on the topic of Acoustics International Commission for Acoustics European Acoustics Association Acoustical Society of America Institute of Noise Control Engineers National Council of Acoustical Consultants Institute of Acoustic in UK Australian Acoustical Society AAS Portal Physics Retrieved from https en wikipedia org w index php title Acoustics amp oldid 1142280334, wikipedia, wiki, book, books, library,

article

, read, download, free, free download, mp3, video, mp4, 3gp, jpg, jpeg, gif, png, picture, music, song, movie, book, game, games.