Acoustics is a branch of physics whose purpose is the study of sound and mechanical waves. It uses the wave phenomena and mechanical vibrations.

As such, the fields of investigation include its proposed several areas:

• the propagation of sound waves ,
• the room acoustics , the physiology of hearing ,
• environmental acoustics,
• the sound processing ,
• the science of speech communication (see the work in linguistics devoted to the non-semantic aspect of the sounds produced by the human voice, the phonetic sound ), etc..

A fortiori, the sound has several ramifications:

• The study of the interpretation of sounds by the human brain based psychoacoustics ,
• production and perception of musical sounds founded the acoustic music.

The musical acoustics to understand the diffusion phenomena of music (venues), the special bills instrumental, and finally, more recently, cognition and reception of music. The computer (see computer music ) and especially the sound synthesis , provided particularly powerful tools to change the means of study.

Summary 1 Anatomy - Physiology 2 Propagation - Room Acoustics 3 Noise and sound pollution 4 Invoice instrumental 5 Applications 6 External link

Anatomy - Physiology

The ear is a very special organ, and the hearing is considered the finest sense. The sound thus explores the physiology, ranging from the pinna to the synaptic correlations in the brain , and psychoacoustic interpretations of those perceptions at the cortical level and cerebral. We can define the acoustic propagation in the air of a sound consisting of a rapid air movement that comes to the human ear
See Hearing

Propagation - Room Acoustics

Applying the theory of propagation of waves of sound waves, it affects an area already well under control since the Antiquity , that of the room acoustics. To amplify sound, the Greeks used the physical properties of materials, the knowledge they had gained on the resorption and refraction of sound, and built amphitheaters giving them a particular shape. Thus, buildings which were to produce speakers and musicians had a very sound study. The theater of Epidaurus in Greece has witnessed the advancement of knowledge in acoustics from the ancient times.

Knowledge in room acoustics at the time of ancient Greece, however, were primarily empirical. This knowledge area will remain very long time almost entirely based on experience, developing as a result of tests sometimes resulting in failure, sometimes at great successes that can serve as a model for the following rooms. American physicist Wallace Clement Sabine is generally considered the father of the room acoustics as a science. In 1900 he published the article 'Reverb' which lays the foundation for this fledgling science.

Nuisance and noise pollution

• Noise : The phenomena of vibro-acoustic coupling are present in the aerospace, automotive, rail and engineering industries in general. Problems related to the improvement of indoor comfort and reducing nuisance external facing them critically.
  Similar problems also arise in the construction industry where the walls and the facades of buildings must be properly sized to reduce noise transmission.
  The acoustic engineer must be able to understand and model the physical phenomena involved, it must acquire the knowledge necessary to implement both analytical and numerical tools to find solutions to improve product terms of noise reduction.

• Pollution : The dictionary of French vocabulary of the environment, we can speak of sound when the consequences of its spread in the environment generate a of ecosystem functioning, generally following the disappearance or the decline of certain species, which do no longer their ecosystem functions.

See also: Soundproofing

Bill instrumental

The earliest form of acoustic amplification correspond to the first musical instruments. Indeed, the sounding of the different instruments are designed to amplify the sound that comes either Strings: harp , violin , guitar , piano ... or tips for wind instruments: flute , flute , trumpet ... This remains true for percussion instruments , and even the human voice : in fact the human body acts as a sounding board for the voice.

Applications