In
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 ...
and
audio
Audio most commonly refers to sound, as it is transmitted in signal form. It may also refer to:
Sound
*Audio signal, an electrical representation of sound
*Audio frequency, a frequency in the audio spectrum
*Digital audio, representation of sound ...
, a transient is a high amplitude, short-duration sound at the beginning of a waveform that occurs in phenomena such as musical sounds, noises or speech.
Transients do not necessarily directly depend on the frequency of the tone they initiate. It contains a high degree of non-periodic components and a higher magnitude of high frequencies than the harmonic content of that sound.
Transients are more difficult to encode with many
audio compression algorithms, causing
pre-echo
In audio signal processing, pre-echo, sometimes called a '' forward echo'', (not to be confused with reverse echo) is a digital audio compression artifact where a sound is heard before it occurs (hence the name). It is most noticeable in impulsiv ...
.
Sonar
The term ''transient'' is used by military
sonar
Sonar (sound navigation and ranging or sonic navigation and ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigation, navigate, measure distances (ranging), communicate with or detect o ...
operators to describe unexpected sounds emanating from another vessel such as operating machinery, a metal hatch being slammed, or the flooding and pressurization of
torpedo
A modern torpedo is an underwater ranged weapon launched above or below the water surface, self-propelled towards a target, and with an explosive warhead designed to detonate either on contact with or in proximity to the target. Historically, su ...
or
vertical launch tubes.
See also
*
Prefix (acoustics)
In acoustics, the prefix of a sound is an initial phase, the onset of a sound quite dissimilar to the ensuing lasting vibration.
The term was coined by J. F. Schouten (1968, 42), who called it one of ''at least five major acoustic parameters'' t ...
*
Impulse function
In mathematics, the Dirac delta distribution ( distribution), also known as the unit impulse, is a generalized function or distribution over the real numbers, whose value is zero everywhere except at zero, and whose integral over the entire ...
*
Onset (audio)
Onset refers to the beginning of a musical note or other sound. It is related to (but different from) the concept of a transient: all musical notes have an onset, but do not necessarily include an initial transient.
Onset detection
In signal pro ...
*
Transient response
In electrical engineering and mechanical engineering, a transient response is the response of a system to a change from an equilibrium or a steady state. The transient response is not necessarily tied to abrupt events but to any event that affec ...
– a common electrical engineering term that may be the source of the idea of an acoustic "transient"
References
{{reflist
Acoustics
Sonar
de:Einschwingvorgang