80-437: (Redirected from Sound System ) Sound system may refer to: Technology media [ edit ] Sound reinforcement system , a system for amplifying audio for an audience High fidelity , a sound system intended for accurate reproduction of music in the home Public address system , an institutional speech-reinforcement or public safety announcement system Shelf stereo ,
160-413: A band-pass filter, eliminating undesirable frequencies both above and below the auditory spectrum. A band-stop filter , does the opposite. It allows all frequencies to pass except for one band in the middle. A feedback suppressor, using an microprocessor , automatically detects the onset of feedback and applies a narrow band-stop filter (a notch filter ) at specific frequency or frequencies pertaining to
240-546: A light bulb with a power rating of 100 W is turned on for one hour, the energy used is 100 watt hours (W·h), 0.1 kilowatt hour, or 360 kJ . This same amount of energy would light a 40-watt bulb for 2.5 hours, or a 50-watt bulb for 2 hours. Power stations are rated using units of power, typically megawatts or gigawatts (for example, the Three Gorges Dam in China is rated at approximately 22 gigawatts). This reflects
320-548: A reverb effect, which outputs a wet (effected) version of the signal, which is typically mixed in varying amounts with the dry (effect-free) signal. Many electronic effects units are used in sound reinforcement systems, including digital delay and reverb . Some concerts use pitch correction effects (e.g., AutoTune ), which electronically correct any out-of-tune singing. Mixing consoles also have additional sends , also referred to as auxes or aux sends (an abbreviation for "auxiliary send"), on each input channel so that
400-406: A "boomy" sounding bass drum , or an overly resonant dreadnought guitar can be cut. Sound reinforcement systems typically use graphic equalizers with one-third octave frequency centers. These are typically used to equalize output signals going to the main loudspeaker system or the monitor speakers on stage. Parametric equalizers are often built into each channel in mixing consoles, typically for
480-442: A 2021 EP by Bad Gyal Sound-System (album) , by Herbie Hancock Soundsystem (311 album) , 1999 "Sound System", a song by Operation Ivy See also [ edit ] Phonology , the study of sound systems of languages Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title Sound system . If an internal link led you here, you may wish to change
560-463: A compact sound system for personal use Amplifier Arts and entertainment [ edit ] Sound system (DJ) , a group of disc jockeys performing together Sound system (Jamaican) , a group of disc jockeys, engineers and MCs playing ska, rocksteady or reggae music Sound System Records , an Australian record label LCD Soundsystem , an American rock band Sound System (album) , by The Clash Sound System: The Final Releases ,
640-492: A constant opposing force of one newton , the rate at which work is done is one watt. 1 W = 1 J / s = 1 N ⋅ m / s = 1 k g ⋅ m 2 ⋅ s − 3 . {\displaystyle \mathrm {1~W=1~J{/}s=1~N{\cdot }m{/}s=1~kg{\cdot }m^{2}{\cdot }s^{-3}} .} In terms of electromagnetism , one watt
720-446: A crossover to separate the sound into low, middle and high frequencies can lead to a "cleaner", clearer sound (see bi-amplification ) than routing all of the frequencies through a single full-range speaker system. Nevertheless, many small venues still use a single full-range speaker system, as it is easier to set up and less expensive. Many types of input transducers can be found in a sound reinforcement system, with microphones being
800-467: A different mix can be created and sent elsewhere for another purpose. One usage for aux sends is to create a mix of the vocal and instrument signals for the monitor mix (this is what the onstage singers and musicians hear from their monitor speakers or in-ear monitors ). Another use of an aux send is to select varying amounts of certain channels (via the aux send knobs on each channel), and then route these signals to an effects processor. A common example of
880-479: A good "ear" for what the music should sound like in order to create a good mix. Multiple consoles can be used for different purposes in a single sound reinforcement system. The front-of-house (FOH) mixing console is typically located where the operator can see the action on stage and hear what the audience hears. For broadcast and recording applications, the mixing console may be placed within an enclosed booth or outside in an OB van . Large music productions often use
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#1732883609342960-411: A live performer. They are either of a universal fit or custom fit design. The universal fit in-ear monitors feature rubber or foam tips that can be inserted into virtually anybody's ear. Custom-fit in-ear monitors are created from an impression of the user's ear that has been made by an audiologist . In-ear monitors are almost always used in conjunction with a wireless transmitting system, allowing
1040-455: A microphone that a vocalist is singing into or a microphone placed in front of an instrument or guitar amplifier . These signal inputs are plugged into the input jacks of a thick multicore cable (often called a snake ). The snake then delivers the signals of all of the inputs to one or more mixing consoles . In a coffeehouse or small nightclub, the snake may be only routed to a single mixing console, which an audio engineer will use to adjust
1120-421: A noise gate, the threshold of sensitivity for each microphone on the drum kit can be set so that only the direct strike and subsequent decay of the drum will be heard, not the nearby sounds. Reverberation and delay effects are widely used in sound reinforcement systems to enhance the sound of the mix and create a desired artistic effect. Reverb and delay add a sense of spaciousness to the sound. Reverb can give
1200-448: A performer or a section of the stage. They are generally sent a different mix of vocals or instruments than the mix that is sent to the main loudspeaker system. Monitor loudspeaker cabinets are often a wedge shape, directing their output upwards towards the performer when set on the floor of the stage. Simple two-way, dual-driver designs with a speaker cone and a horn are common, as monitor loudspeakers need to be smaller to save space on
1280-439: A person singing into an electric signal, signal processors which alter the signal characteristics (e.g., equalizers that adjust the bass and treble, compressors that reduce signal peaks, etc.), amplifiers , which produce a powerful version of the resulting signal that can drive a loudspeaker and output transducers (e.g., loudspeakers in speaker cabinets ), which convert the signal back into sound energy (the sound heard by
1360-405: A problem. Digital effects units may offer multiple pre-set and variable reverb, echo and related effects . Digital loudspeaker management systems offer sound engineers digital delay (to ensure speakers are in sync with each other), limiting, crossover functions, EQ filters, compression and other functions in a single rack-mountable unit. In previous decades, sound engineers typically had to transport
1440-566: A separate stage monitor mixing console which is dedicated to creating mixes for the performers on-stage. These consoles are typically placed at the side of the stage so that the operator can communicate with the performers on stage. Small PA systems for venues such as bars and clubs are now available with features that were formerly only available on professional-level equipment, such as digital reverb effects, graphic equalizers , and, in some models, feedback prevention circuits which electronically sense and prevent audio feedback when it becomes
1520-417: A single unit are used to process the mix from the mixing console and route it to the various amplifiers. Systems may include several loudspeakers, each with its own output optimized for a specific range of frequencies (i.e. bass, midrange, and treble). Bi-amping and tri-amping of a sound reinforcement system with the aid of a DLMS results in more efficient use of amplifier power by sending each amplifier only
1600-497: A small public address (PA) system, consisting of, for example, a single microphone connected to a 100-watt amplified loudspeaker for a singer-guitarist playing in a small coffeehouse . In both cases, these systems reinforce sound to make it louder or distribute it to a wider audience. Some audio engineers and others in the professional audio industry disagree over whether these audio systems should be called sound reinforcement (SR) systems or PA systems. Distinguishing between
1680-479: A substantial number of rack-mounted analog effects unit devices to accomplish these tasks. Equalizers are electronic devices that allow audio engineers to control the tone and frequencies of the sound in a channel, group (e.g., all the mics on a drumkit) or an entire stage's mix. The bass and treble controls on a home stereo are a simple type of equalizer. Equalizers exist in professional sound reinforcement systems in three forms: shelving equalizers (typically for
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#17328836093421760-535: A turbine, which generates 648 MW e (i.e. electricity). Other SI prefixes are sometimes used, for example gigawatt electrical (GW e ). The International Bureau of Weights and Measures , which maintains the SI-standard, states that further information about a quantity should not be attached to the unit symbol but instead to the quantity symbol (e.g., P th = 270 W rather than P = 270 W th ) and so these unit symbols are non-SI. In compliance with SI,
1840-486: A unit of time, namely 1 J/s. In this new definition, 1 absolute watt = 1.00019 international watts. Texts written before 1948 are likely to be using the international watt, which implies caution when comparing numerical values from this period with the post-1948 watt. In 1960, the 11th General Conference on Weights and Measures adopted the absolute watt into the International System of Units (SI) as
1920-460: A whole range of bass and treble frequencies), graphic equalizers and parametric equalizers . Graphic equalizers have faders (vertical slide controls) which together resemble a frequency response curve plotted on a graph. The faders can be used to boost or cut specific frequency bands. Using equalizers, frequencies that are too weak, such as a singer with modest projection in their lower register, can be boosted. Frequencies that are too loud, such as
2000-595: Is intentional, so the sound engineer does not try to prevent it. A power amplifier is an electronic device that uses electrical power and circuitry to boost a line level signal and provides enough electrical power to drive a loudspeaker and produce sound. All loudspeakers, including headphones , require power amplification. Most professional audio power amplifiers also provide protection from clipping typically as some form of limiting . A power amplifier pushed into clipping can damage loudspeakers. Amplifiers also typically provide protection against short circuits across
2080-700: Is named after the Scottish inventor James Watt . The unit name was proposed by C. William Siemens in August 1882 in his President's Address to the Fifty-Second Congress of the British Association for the Advancement of Science . Noting that units in the practical system of units were named after leading physicists, Siemens proposed that watt might be an appropriate name for a unit of power. Siemens defined
2160-406: Is not relevant to the program, such as the hum of a miked electric guitar amplifier or the rustling of papers on a minister's lectern. Noise gates are also used to process the microphones placed near the drums of a drum kit in many hard rock and metal bands. Without a noise gate, the microphone for a specific instrument such as the floor tom will also pick up signals from nearby drums or cymbals. With
2240-402: Is quite subjective and is often collectively determined by a production's audio engineer, artists, bandleader , music producer , or musical director. A feedback suppressor detects unwanted audio feedback and suppresses it, typically by automatically inserting a notch filter into the signal path of the system. Audio feedback can create unwanted loud, screaming noises that are disruptive to
2320-478: Is the combination of microphones , signal processors , amplifiers , and loudspeakers in enclosures all controlled by a mixing console that makes live or pre-recorded sounds louder and may also distribute those sounds to a larger or more distant audience. In many situations, a sound reinforcement system is also used to enhance or alter the sound of the sources on the stage, typically by using electronic effects , such as reverb , as opposed to simply amplifying
2400-523: Is the rate at which electrical work is performed when a current of one ampere (A) flows across an electrical potential difference of one volt (V), meaning the watt is equivalent to the volt-ampere (the latter unit, however, is used for a different quantity from the real power of an electrical circuit). 1 W = 1 V ⋅ A . {\displaystyle \mathrm {1~W=1~V{\cdot }A} .} Two additional unit conversions for watt can be found using
2480-516: Is used to quantify the rate of energy transfer . The watt is named in honor of James Watt (1736–1819), an 18th-century Scottish inventor , mechanical engineer , and chemist who improved the Newcomen engine with his own steam engine in 1776. Watt's invention was fundamental for the Industrial Revolution . When an object's velocity is held constant at one meter per second against
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2560-549: The Audio Engineering Society (AES) and the loudspeaker industry group ALMA in developing the EIA-426 testing standard, power-handling specifications became more trustworthy. Lightweight, portable speaker systems for small venues route the low-frequency parts of the music (electric bass, bass drum, etc.) to a powered subwoofer . Routing the low-frequency energy to a separate amplifier and subwoofer can substantially improve
2640-401: The exciter and harmonizer . The use of effects in the reproduction of 2010-era pop music is often in an attempt to mimic the sound of the studio version of the artist's music in a live concert setting. For example, an audio engineer may use an Auto Tune effect to produce unusual vocal sound effects that a singer used on their recordings. The appropriate type, variation, and level of effects
2720-908: The stage monitor system . Microphones used for sound reinforcement are positioned and mounted in many ways, including base-weighted upright stands, podium mounts, tie-clips, instrument mounts, and headset mounts . Microphones on stands are also placed in front of instrument amplifiers to pick up the sound. Headset-mounted and tie-clip-mounted microphones are often used with wireless transmission to allow performers or speakers to move freely. Early adopters of headset mounted microphones technology included country singer Garth Brooks , Kate Bush , and Madonna . Other types of input transducers include magnetic pickups used in electric guitars and electric basses, contact microphones used on stringed instruments, and pianos and phonograph pickups (cartridges) used in record players. Electronic instruments such as synthesizers can have their output signal routed directly to
2800-467: The above equation and Ohm's law . 1 W = 1 V 2 / Ω = 1 A 2 ⋅ Ω , {\displaystyle \mathrm {1~W=1~V^{2}/\Omega =1~A^{2}{\cdot }\Omega } ,} where ohm ( Ω {\displaystyle \Omega } ) is the SI derived unit of electrical resistance . The watt
2880-420: The audience and the performers). These primary parts involve varying numbers of individual components to achieve the desired goal of reinforcing and clarifying the sound to the audience, performers, or other individuals. Sound reinforcement in a large format system typically involves a signal path that starts with the signal inputs, which may be instrument pickups (on an electric guitar or electric bass ) or
2960-832: The back wall of the stage out into vocal mics and the audience, which improves the clarity of the front-of-house mix. Sound reinforcement systems are used in a broad range of different settings, each of which poses different challenges. Audio-visual rental systems have to be able to withstand heavy use and even abuse from renters. For this reason, rental companies tend to own speaker cabinets that are heavily braced and protected with steel corners, and electronic equipment such as power amplifiers or effects are often mounted into protective road cases. Rental companies also tend to select gear that have electronic protection features, such as speaker-protection circuitry and amplifier limiters. Rental systems for non-professionals need to be easy to use and set up and they must be easy to repair and maintain for
3040-577: The bass response of the system. Also, clarity may be enhanced because low-frequency sounds can cause intermodulation and other distortion in speaker systems. Professional sound reinforcement speaker systems often include dedicated hardware for safely flying them above the stage area, to provide more even sound coverage and to maximize sightlines within performance venues. Monitor loudspeakers , also called foldback loudspeakers, are speaker cabinets used onstage to help performers to hear their singing or playing. As such, monitor speakers are pointed towards
3120-756: The cooling capabilities of the amplifier. In the 1970s and 1980s, most PAs employed heavy class AB amplifiers . In the late 1990s, power amplifiers in PA applications became lighter, smaller, more powerful, and more efficient, with the increasing use of switching power supplies and class D amplifiers , which offered significant weight- and space-savings as well as increased efficiency. Often installed in railroad stations, stadia, and airports, class D amplifiers can run with minimal additional cooling and with higher rack densities, compared to older amplifiers. Digital loudspeaker management systems (DLMS) that combine digital crossover functions, compression, limiting, and other features in
3200-515: The different frequencies to the appropriate drivers. In the 1960s, horn loaded theater and PA speakers were commonly columns of multiple drivers mounted in a vertical line within a tall enclosure. The 1970s to early 1980s was a period of innovation in loudspeaker design with many sound reinforcement companies designing their own speakers using commercially available drivers. The areas of innovation were in cabinet design, durability, ease of packing and transport, and ease of setup. This period also saw
3280-531: The effect of singing voice or instrument being present in anything from a small room to a massive hall, or even in a space that does not exist in the physical world. The use of reverb often goes unnoticed by the audience, as it often sounds more natural than if the signal was left "dry" (without effects). Many modern mixing boards designed for live sound include on-board reverb effects. Other effects include modulation effects such as Flanger , phaser , and chorus and spectral manipulation or harmonic effects such as
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3360-515: The energy company Ørsted A/S uses the unit megawatt for produced electrical power and the equivalent unit megajoule per second for delivered heating power in a combined heat and power station such as Avedøre Power Station . When describing alternating current (AC) electricity, another distinction is made between the watt and the volt-ampere . While these units are equivalent for simple resistive circuits , they differ when loads exhibit electrical reactance . Radio stations usually report
3440-399: The feedback. Dynamic range compression is designed to help the audio engineer to manage the dynamic range of audio signals. Prior to the invention of automatic compressors, audio engineers accomplished the same goal by "riding the faders", listening carefully to the mix and lowering the faders of any singer or instrument which was getting too loud. A compressor accomplishes this by reducing
3520-441: The frequencies appropriate for its respective loudspeaker and eliminating losses associated with passive crossover circuits. A simple and inexpensive PA loudspeaker may have a single full-range loudspeaker driver , housed in a suitable enclosure. More elaborate, professional-caliber sound reinforcement loudspeakers may incorporate separate drivers to produce low, middle, and high frequency sounds. A crossover network routes
3600-409: The gain of a signal that is above a defined level (the threshold) by a defined amount determined by the ratio setting. Most compressors available are designed to allow the operator to select a ratio within a range typically between 1:1 and 20:1, with some allowing settings of up to ∞:1. A compressor with high compression ratio is typically referred to as a limiter . The speed that the compressor adjusts
3680-423: The gain of the signal ( attack and release ) is typically adjustable as is the final output or make-up gain of the device. Compressor applications vary widely. Some applications use limiters for component protection and gain structure control. Artistic signal manipulation using a compressor is a subjective technique widely utilized by mix engineers to improve clarity or to creatively alter the signal in relation to
3760-465: The heart of a sound reinforcement system. This is where the sound engineer can adjust the volume and tone of each input, whether it is a vocalist's microphone or the signal from an electric bass , and mix, equalize and add effects to these sound sources. Doing the mixing for a live show requires a mix of technical and artistic skills. A sound engineer needs to have an expert knowledge of speaker and amplifier set-up, effects units and other technologies and
3840-487: The implementation. Many sound reinforcement loudspeaker systems incorporate protection circuitry to prevent damage from excessive power or operator error. Resettable fuses , specialized current-limiting light bulbs, and circuit breakers were used alone or in combination to reduce driver failures. During the same period, the professional sound reinforcement industry made the Neutrik Speakon NL4 and NL8 connectors
3920-426: The in-ear monitor sends. Since their introduction in the mid-1980s, in-ear monitors have grown to be the most popular monitoring choice for large touring acts. The reduction or elimination of loudspeakers other than instrument amplifiers on stage has allowed for cleaner and less problematic mixing for both the front of house and monitor engineers. Audio feedback is greatly reduced and there is less sound reflecting off
4000-405: The in-ear monitors of one performer cannot be heard by the other musicians. A downside of this isolation is that the performer cannot hear the crowd or the comments from other performers on stage that do not have microphones (e.g., if the bass player wishes to communicate to the drummer). This has been remedied in larger productions by setting up microphones facing the audience that can be mixed into
4080-415: The introduction of the hanging or flying of main loudspeakers at large concerts. During the 1980s the large speaker manufacturers started producing standard products using the innovations of the 1970s. These were mostly smaller two way systems with 12", 15" or double 15" woofers and a high frequency driver attached to a high frequency horn. The 1980s also saw the start of loudspeaker companies focused on
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#17328836093424160-410: The link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Sound_system&oldid=1237121050 " Category : Disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages Sound reinforcement system A sound reinforcement system
4240-486: The main mix for the audience at FOH and another to do the monitor mix for the performers on stage. Once the signal arrives at an input on a mixing console, this signal can be adjusted in many ways by the sound engineer. A signal can be equalized (e.g., by adjusting the bass or treble of the sound), compressed (to avoid unwanted signal peaks), or panned (that is sent to the left or right speakers). The signal may also be routed into an external effects processor , such as
4320-737: The main outputs are often sent to an additional equalizer, or directly to a power amplifier , with one or more loudspeakers (typically two, one on each side of the stage in smaller venues, or a large number in big venues) that are connected to that amplifier. In large-format systems, the signal is typically first routed through an equalizer then to a crossover . A crossover splits the signal into multiple frequency bands with each band being sent to separate amplifiers and speaker enclosures for low, middle, and high-frequency signals. Low-frequency signals are sent to amplifiers and then to subwoofers , and middle and high-frequency sounds are typically sent to amplifiers which power full-range speaker cabinets. Using
4400-460: The maximum power output it can achieve at any point in time. A power station's annual energy output, however, would be recorded using units of energy (not power), typically gigawatt hours. Major energy production or consumption is often expressed as terawatt hours for a given period; often a calendar year or financial year. One terawatt hour of energy is equal to a sustained power delivery of one terawatt for one hour, or approximately 114 megawatts for
4480-414: The mid-range frequencies. They are also available as separate rack-mount units that can be connected to a mixing board. Parametric equalizers typically use knobs and sometimes buttons. The audio engineer can select which frequency band to cut or boost, and then use additional knobs to adjust how much to cut or boost this frequency range. Parametric equalizers first became popular in the 1970s and have remained
4560-401: The mixing console. A DI unit may be necessary to adapt some of these sources to the inputs of the console. Wireless systems are typically used for electric guitar, bass, handheld microphones and in-ear monitor systems. This lets performers move about the stage during the show or even go out into the audience without the worry of tripping over or disconnecting cables. Mixing consoles are
4640-434: The most commonly used input device. Microphones can be classified according to their method of transduction, polar pattern or their functional application. Most microphones used in sound reinforcement are either dynamic or condenser microphones. One type of directional microphone, called cardioid mics, are widely used in live sound, because they reduce pickup from the side and rear, helping to avoid unwanted feedback from
4720-542: The output and overheating. Audio engineers select amplifiers that provide enough headroom . Headroom refers to the amount by which the signal-handling capabilities of an audio system exceed a designated nominal level . Headroom can be thought of as a safety zone allowing transient audio peaks to exceed the nominal level without damaging the system or the audio signal, e.g., via clipping . Standards bodies differ in their recommendations for nominal level and headroom. Selecting amplifiers with enough headroom helps to ensure that
4800-424: The performance, and can damage speakers and performers' and audience members' ears. Audio feedback from microphones occurs when a microphone is too near a monitor or main speaker and the sound reinforcement system amplifies itself. Audio feedback through a microphone is almost universally regarded as a negative phenomenon, many electric guitarists use guitar feedback as part of their performance. This type of feedback
4880-404: The performer to freely move about the stage while receiving their monitor mix. In-ear monitors offer considerable isolation for the performer using them: no on-stage sound is heard and the monitor engineer can deliver a much more accurate and clear mix for the performer. With in-ear monitors, each performer can be sent their own customized mix; although this was also the case with monitor speakers,
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#17328836093424960-501: The performers in front of them. The clarity of the mix for the performer on stage is also typically compromised as they hear more extraneous noise from around them. The use of monitor loudspeakers, active (with an integrated amplifier) or passive, requires more cabling and gear on stage, resulting in a more cluttered stage. These factors, amongst others, have led to the increasing popularity of in-ear monitors. In-ear monitors are headphones that have been designed for use as monitors by
5040-488: The power of their transmitters in units of watts, referring to the effective radiated power . This refers to the power that a half-wave dipole antenna would need to radiate to match the intensity of the transmitter's main lobe . The terms power and energy are closely related but distinct physical quantities. Power is the rate at which energy is generated or consumed and hence is measured in units (e.g. watts) that represent energy per unit time . For example, when
5120-446: The program equalizer of choice for many engineers since then. A high-pass (low-cut) and/or low-pass (high-cut) filter may also be included on equalizers or audio consoles. High-pass and low-pass filters restrict a given channel's bandwidth extremes. Cutting very low-frequency sound signals (termed infrasonic , or subsonic ) reduces the waste of amplifier power which does not produce audible sound and which moreover can be hard on
5200-427: The program material. An example of artistic compression is the typical heavy compression used on the various components of a modern rock drum kit. The drums are processed to be perceived as sounding more punchy and full. A noise gate mutes signals below a set threshold level. A noise gate's function is in, a sense, opposite to that of a compressor. Noise gates are useful for microphones which will pick up noise that
5280-457: The rental company that tour with the band to set up and calibrate the equipment. The individual that mixes the band is often selected and provided by the band, as they are familiar with the various aspects of the show and understand how the band wants the show to sound. Watt The watt (symbol: W ) is the unit of power or radiant flux in the International System of Units (SI), equal to 1 joule per second or 1 kg⋅m ⋅s . It
5360-465: The renting company. From this perspective, speaker cabinets need to have easy-to-access horns, speakers, and crossover circuitry, so that repairs or replacements can be made. Many touring acts and large venue corporate events will rent large sound reinforcement systems that typically include one or more audio engineers on staff with the renting company. In the case of rental systems for tours, there are typically several audio engineers and technicians from
5440-459: The requirements of the loudspeaker. Some active loudspeakers also have equalization, crossover and mixing circuitry built in. Since amplifiers can generate a significant amount of heat, thermal dissipation is an important factor for operators to consider when mounting amplifiers into equipment racks. Many power amplifiers feature internal fans to draw air across their heat sinks. The heat sinks can become clogged with dust, which can adversely affect
5520-435: The second use of aux sends is to send all of the vocal signals from a rock band through a reverb effect. While reverb is usually added to vocals in the main mix, it is not usually added to electric bass and other rhythm section instruments. The processed input signals are then mixed to the master faders on the console. The next step in the signal path generally depends on the size of the system in place. In smaller systems,
5600-409: The signal will remain clean and undistorted. Like most sound reinforcement equipment, professional power amplifiers are typically designed to be mounted within standard 19-inch racks . Rack-mounted amps are typically housed in road cases to prevent damage to the equipment during transportation. Active loudspeakers have internally mounted amplifiers that have been selected by the manufacturer to match
5680-478: The sound and volume of the onstage vocals and instruments that the audience hears through the main speakers and adjust the volume of the monitor speakers that are aimed at the performers. Mid- to large-size performing venues typically route the onstage signals to two mixing consoles : the front of house (FOH), and the stage monitor system , which is often a second mixer at the side of the stage. In these cases, at least two audio engineers are required; one to do
5760-672: The sound reinforcement market. The 1990s saw the introduction of line arrays , where long vertical arrays of loudspeakers in smaller cabinets are used to increase efficiency and provide even dispersion and frequency response. Trapezoidal -shaped enclosures became popular as this shape allowed many of them to be easily arrayed together. This period also saw the introduction of inexpensive molded plastic speaker enclosures mounted on tripod stands. Many feature built-in power amplifiers which made them practical for non-professionals to set up and operate successfully. The sound quality available from these simple powered speakers varies widely depending on
5840-417: The sources unaltered. A sound reinforcement system for a rock concert in a stadium may be very complex, including hundreds of microphones, complex live sound mixing and signal processing systems, tens of thousands of watts of amplifier power, and multiple loudspeaker arrays , all overseen by a team of audio engineers and technicians. On the other hand, a sound reinforcement system can be as simple as
5920-618: The stage. These loudspeakers typically require less power and volume than the main loudspeaker system, as they only need to provide sound for a few people who are in relatively close proximity to the loudspeaker. Some manufacturers have designed loudspeakers for use either as a component of a small PA system or as a monitor loudspeaker. A number of manufacturers produce powered monitor speakers , which contain an integrated amplifier. Using monitor speakers instead of in-ear monitors typically results in an increase of stage volume, which can lead to more feedback issues and progressive hearing damage for
6000-411: The standard speaker connectors, replacing 1/4" jacks , XLR connectors , and Cannon multipin connectors which are all limited to a maximum of 15 amps of current. XLR connectors are still the standard input connector on active loudspeaker cabinets. To help users avoid overpowering them, loudspeakers have a power rating (in watts ) which indicates their maximum power capacity. Thanks to the efforts of
6080-399: The subwoofer drivers. A low-pass filter to cut ultrasonic energy is useful to prevent interference from radio frequencies, lighting control, or digital circuitry creeping into the power amplifiers. Such filters are often paired with graphic and parametric equalizers to give the audio engineer full control of the frequency range. High-pass filters and low-pass filters used together function as
6160-530: The two terms by technology and capability is common, while others distinguish by intended use (e.g., SR systems are for live event support and PA systems are for reproduction of speech and recorded music in buildings and institutions). In some regions or markets, the distinction between the two terms is important, though the terms are considered interchangeable in many professional circles. A typical sound reinforcement system consists of; input transducers (e.g., microphones ), which convert sound energy such as
6240-559: The unit of power. In the electric power industry , megawatt electrical ( MWe or MW e ) refers by convention to the electric power produced by a generator, while megawatt thermal or thermal megawatt (MWt, MW t , or MWth, MW th ) refers to thermal power produced by the plant. For example, the Embalse nuclear power plant in Argentina uses a fission reactor to generate 2,109 MW t (i.e. heat), which creates steam to drive
6320-556: The unit within the existing system of practical units as "the power conveyed by a current of an Ampère through the difference of potential of a Volt". In October 1908, at the International Conference on Electric Units and Standards in London, so-called international definitions were established for practical electrical units. Siemens' definition was adopted as the international watt. (Also used: 1 A × 1 Ω.) The watt
6400-420: Was defined as equal to 10 units of power in the practical system of units. The "international units" were dominant from 1909 until 1948. After the 9th General Conference on Weights and Measures in 1948, the international watt was redefined from practical units to absolute units (i.e., using only length, mass, and time). Concretely, this meant that 1 watt was defined as the quantity of energy transferred in
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