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Encyclopedia > Spring reverb

Reverberation is the persistence of sound in a particular space after the original sound is removed. When sound is produced in a space, a large number of echoes build up and then slowly decay as the sound is absorbed by the walls and air, creating reverberation, or reverb. This is most noticeable when the sound source stops but the reflections continue, decreasing in amplitude, until they can no longer be heard. Large chambers, especially such as cathedrals, gymnasiums, indoor swimming pools, large caves, etc., are examples of spaces where the reverberation time is long and can clearly be heard. Different types of music tend to sound best with reverberation times appropriate to their characteristics. Image File history File links Broom_icon. ... Reverb may refer to: Reverb, a TV series Reverberation, an audio effect Reverb (film), a 2007 movie Reverberation (album), an album by Echo & the Bunnymen Reverberation (record label), a record label Category: ... Sound is a disturbance of mechanical energy that propagates through matter as a longitudinal wave, and therefore is a mechanical wave. ... ECHO is a German music award granted every year by the Deutsche Phono-Akademie (an association of recording companies). ... Look up reflection in Wiktionary, the free dictionary. ... Amplitude is a nonnegative scalar measure of a waves magnitude of oscillation, that is, magnitude of the maximum disturbance in the medium during one wave cycle. ... 50 meter indoor swimming pool A swimming pool, swimming bath, or wading pool is an artificially enclosed body of water intended for recreational or competitive swimming, or for other bathing activities that do not involve swimming, i. ... It has been suggested that this article or section be merged into reverberation. ...


(Compare with echo: "If so many reflections arrive at a listener that he is unable to distinguish between them, the proper term is reverberation.") ECHO is a German music award granted every year by the Deutsche Phono-Akademie (an association of recording companies). ...

  • Short sample of reverberation effect ( file info) — play in browser (beta)
    • Clean signal, followed by different versions of reverberation (with longer and longer decay times).
    • Problems listening to the file? See media help.

Contents

Image File history File links Reverberation_effect. ... Software development stages In computer programming, development stage terminology expresses how the development of a piece of software has progressed and how much further development it may require. ...

Reverberation Time

Reverberation time is the time required for a sound in a room to decay by 60 dB (called RT60). Reverberation time is defined for wide band signals. When talking about the decay of an individual frequency, the term decay time is used. DB or db or dB may stand for: Database, an organized collection of data David Belle, founder of parkour DB connector, improper term for D-subminiature DB (car), a French automobile maker Dragon Ball, a manga and anime. ...


In the late 19th century, Wallace Clement Sabine started experiments at Harvard University to investigate the impact of absorption on the reverberation time. Using a portable wind chest and organ pipes as a sound source, a stopwatch and a clean pair of ears he measured the time from interruption of the source to inaudibility (roughly 60dB). This time varies directly with the dimensions of room but inversely as the absorption present. Alternative meaning: Nineteenth Century (periodical) (18th century — 19th century — 20th century — more centuries) As a means of recording the passage of time, the 19th century was that century which lasted from 1801-1900 in the sense of the Gregorian calendar. ... Wallace Clement Sabine (June 13, 1868 - January 10, 1919) was an American physicist who founded the field of architectural acoustics. ... A stopwatch is a timepiece designed to measure the amount of time elapsed from a particular time when activated to when the piece is deactivated. ...


The best reverberation time for a space in which music is played depends on the size of the room and the type of music. Rooms for speech require a shorter reverberation time than for music. A longer reverberation time can make it difficult to understand speech. If the reverberation time from one syllable over laps the next syllable, it may make it difficult to identify the word [1]. "Cat", "Cab", and "Cap" may all sound very similar. If on the other hand the reverberation time is too short, tonal balance and loudness may suffer. Reverberation effects are often used in studios to "smooth" sounds; the effect is commonly used on vocals to help remove inconsistencies in pitch. A syllable (Ancient Greek: ) is a unit of organization for a sequence of speech sounds. ... A recording studio is a facility for sound recording. ...


Basic factors that affect a room's reverberation time include the size and shape of the enclosure as well as the materials used in the construction of the room. Every object placed within the enclosure can also affect this reverberation time, including people and their belongings. It has been suggested that this article or section be merged into reverberation. ...


The Sabine Equation

Sabine's reverberation equation was developed in the late 1890s in an empirical fashion. He established a relationship between the RT60 of a room, its volume, and its total adsorption (in sabins). This is given by the equation: A central concept in science and the scientific method is that all evidence must be empirical, or empirically based, that is, dependent on evidence or consequences that are observable by the senses. ... Sabine (in Latin and in Italian, Sabina) is a sub-region of Latium, Italy, on the North-East of Rome toward Rieti. ...

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where c is a mathematical constant measuring 0.161, V is the volume of the room in m3, S total surface area of room in m2, a is the average adsorption coefficient of room surfaces, and Sa is the total adsorption in sabins.


It is worth noting that the total absorption in sabins (and hence reverberation time) generally changes depending on frequency (dependent on the which is defined by the acoustic properties of the space), and that the equation does not take into account room shape or dimensions, nor losses from the sound travelling through the air (important in larger spaces). In general most rooms adsorb less in the lower frequencies, causing a longer decay time. Acoustics is a branch of physics and is the study of sound (mechanical waves in gases, liquids, and solids). ...


The reverberation time RT60 and the volume V of the room have great influence on the critical distance dc (conditional equation): The volume of a solid object is the three-dimensional concept of how much space it occupies, often quantified numerically. ... In audio physics, the distance at which the sound pressure level of the direct and the reverberant field are equal. ...

where critical distance rH is measured in metres, volume V is measured in m3, and reverberation time RT60 is measured in seconds. The metre (or meter, see spelling differences) is a measure of length. ... Look up second in Wiktionary, the free dictionary. ...


Absorption

The absorption coefficient of a material is a number between 0 and 1 which indicates the proportion of sound which is absorbed by the surface compared to the proportion which is reflected back into the room. A large, fully open window would offer no reflection as any sound reaching it would pass straight out and no sound would be reflected. This would have an absorption coefficient of 1. Conversely, a thick, smooth painted concrete ceiling would be the acoustic equivalent of a mirror, and would have an absorption coefficient very close to 0.


Measurement of Reverberation Time

Historically reverberation time could only be measured using a level recorder (a plotting device which graphs the noise level against time on a ribbon of moving paper). A loud noise is produced, and as the sound dies away the trace on the level recorder will show a distinct slope. Analysis of this slope reveals the measured reverberation time. Modern digital sound level meters carry out this analysis automatically, on digital data. Integrating sound level meter in dB(A) A sound level meter is used to measure sound levels, usually in terms of subjective loudness. ...


Two basic methods exist for creating a sufficiently loud noise (which must have a defined cut off point). Impulsive noise sources such as a blank pistol shot, or balloon burst may be used to measure the impulse response of a room. Alternatively, a random noise signal such as pink noise or white noise may be generated through a loudspeaker, and then turned off. This is known as the interrupted method, and the measured result is known as the interrupted response.


Reverberation time is often given as a measurement of decay time. Decay time is the time it takes the signal to diminish 60 dB below the original sound.


Creating Reverberation Effects

It is often desirable to create a reverberation effect for recorded or live music. A number of systems have been developed to facilitate or simulate reverberation.


Chamber reverberators

The first reverb effects created for recordings used a real physical space as a natural echo chamber. A loudspeaker would play the sound, and then a microphone would pick it up again, including the effects of reverb. Whilst this is still a common technique, it requires a dedicated soundproofed room, and varying the reverb time is difficult. This article is about the technological device. ... “Loudspeaker” redirects here. ... A Neumann U87 capacitor microphone A microphone, sometimes referred to as a mike or mic (both IPA pronunciation: ), is an acoustic to electric transducer or sensor that converts sound into an electrical signal. ...


Plate reverberators

A plate reverb system uses an electromechanical transducer, similar to the driver in a loudspeaker, to create vibration in a plate of sheet metal. A pickup captures the vibrations as they bounce across the plate, and the result is output as an audio signal. A transducer is a device, usually electrical or electronic, that converts one type of energy to another. ... Sheets of stainless steel cover the Chrysler Building Thin sheets of gold leaf Sheet metal is simply metal formed into thin and flat pieces. ... Three magnetic pickups on an electric guitar. ...


Spring reverberators

A spring reverb system uses a transducer at one end of a spring and a pickup at the other, similar to those used in plate reverbs, to create and capture vibrations within a metal spring. Guitar amplifiers frequently incorporate spring reverbs due to their compact construction. Spring reverberators were once widely used in semi-professional recording due to their modest cost and small size. Due to quality problems and improved digital reverb units, spring reverberators are declining rapidly in use. Helical or coil springs designed for tension A spring is a flexible elastic object used to store mechanical energy. ... This article or section does not adequately cite its references or sources. ...


Digital reverberators

Digital reverberators use various signal processing algorithms in order to create the reverb effect. Since reverberation is essentially caused by a very large number of echoes, simple DSPs use multiple feedback delay circuits to create a large, decaying series of echoes that die out over time. More advanced digital reverb generators can simulate the time and frequency domain responses of real rooms (based upon room dimensions, absorption and other properties). In real music halls, the direct sound always arrives at the listeners ear first because it follows the shortest path. Shortly after the direct sound, the reverberant sound arrives. The time between the two is called the 'arrival time gap'. This gap is important in recorded music because it is the cue that gives the ear information on the size of the hall, better digital reverbs can incorporate this arrival time gap and hence sound more realistic. Digital reverb systems are commonly implemented as software plugins. Digital signal processing (DSP) is the study of signals in a digital representation and the processing methods of these signals. ... Delay is an audio effect which records an input signal to an audio storage medium, and then plays it back after a period of time[1]. The delayed signal may either be played back multiple times, or played back into the recording again, to create the sound of a repeating... A plugin (plug-in, addin, add-in, addon or add-on) is a computer program that interacts with a main (or host) application (a web browser or an email program, for example) to provide a certain, usually very specific, function on demand. ...


Convolution Reverb

Main article: Convolution reverb

Convolution reverb is a type of process in which a physical space is sampled by means of an impulse response (IR), so it can be used in audio applications. ...

External links

  • [http://3345.com.au/sitemap.htm Articles
  • Plate-Sonics[2]Builders of real plate reverb

See also



 

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