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| {{About|frequency-dependent processing of audio signals|processing of other types of signals|Equalization|other uses|Equalization (disambiguation)}}
| | Very merely, organic infant food is that which is processed with no the use of artificial pesticides and/or synthetic fertilizers. While a lot of note organic food as becoming either retailer-purchased, garden grown or gathered in the wild, the correct association is certified organic foods, which are made and labeled according to strict regulatory requirements. In a quantity of nations, like the United States, the use of the word organic in the commercial industry, with out the suitable certification, is prohibited by law.<br><br> |
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| [[image:Graphic equalizer.jpg|thumb|A stereo graphic equalizer]]
| | Organic child food is most typically identified in a supermarket and will be labeled accordingly. Simply because of its nature, organic child food is a lot more costly than other sorts. Processed organic baby food usually consists of only those components that are organic and has no artificial food additives. While there appear to a number of rewards to utilizing organic child food, the most frequent purpose for getting this sort of item is the general good quality. Elevated nutritional value, the absence of residues from artificial pesticides and much better taste are all good rewards of organic infant food.<br><br>Organic child food, due to the fact it is believed to be fresher, typically carries an improved taste over other baby foods. Because organic farms are little, their items are most commonly sold close to residence. Therefore, organic baby food and other merchandise function a fresher taste merely because they are fresh.<br><br>By 2003, organic food goods had been obtainable in 20,000 natural food stores and 73% of commercial grocery retailers. While many believe that organic infant food is beneficial, other people are not as specific. Some think that farming and organic fertilization might carry its personal dangers that might be passed along in organic child food.<br><br>The principal debate lies with the much better approach to manufacturing organic food. [http://wilderdom.com/tools/leq/wiki/doku.php?id=Plantar_Fasciitis_Reason_For_The_Harrowing_Heel_Suffering_61868 Plantar Fasciitis Reason For The Harrowing Heel Suffering 61868 [Leq]] is a stately online library for additional resources about the reason for it. Is it far more wholesome to use artificial and synthetic items in food processing or all-natural fertilizer and organic farming strategies? There are both sides to any debate and the inquiries surrounding organic baby food is no distinct. There is legitimate concern over contamination and safety of organic food and goods, but an exact determination as to which side of the table is appropriate has yet to be decided.<br><br>The details in this write-up is to be used for informational purposes. If you are interested in food, you will probably need to research about [http://www.zgtnbw.com/showthread.php?tid=5377 What is a News Release]. [http://www.romybeard.com/what-do-you-you-should-buy-to-transform-your-kitchen/ What Do You You Should Buy To Transform Your Kitchen?] contains further concerning why to see it. It ought to not be deemed as, or utilised in conjunction with, skilled medical guidance or suggested feeding for your infant, toddler or young child. Prior to starting any food preparation involving the use of organic infant food, check with your childs physician for further information and/or a recommendation regarding the use of organic infant food as element of your childs food intake..Western Business Journal<br><br>If you adored this article and you would certainly such as to get more details pertaining to [http://secretiveflaw2645.blogs.experienceproject.com health assessment] kindly check out our own web-page. |
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| In [[sound recording and reproduction]], '''equalization''' is the [[audio signal processing|process]] commonly used to alter the [[frequency response]] of an audio system using [[linear filter]]s. Most [[hi-fi]] equipment uses relatively simple filters to make [[Bass (sound)|bass]] and [[Treble (sound)|treble]] adjustments. Graphic and parametric equalizers have much more flexibility in tailoring the frequency content of an audio signal. An '''equalizer''' is the circuit or equipment used to achieve equalization.<ref name="Strong 2005 25">{{cite book |last=Strong |first= Jeff |title= PC Recording Studios for Dummies |url= http://books.google.com/books?id=4-2SfnghnYwC&dq=pc+recording+studios+for+dummies&source=gbs_navlinks_s|publisher= For Dummies |year= 2005|page=25}}</ref><ref name="The Audio Dictionary">{{cite book|last1=Louie|first1=Gary|last2= White|first2= Glenn|title=The Audio Dictionary|url=http://books.google.com/books?id=DulVm8t88QkC&dq=the+audio+dictionary&source=gbs_navlinks_s|year=2005|publisher= University of Washington Press,|page=140}}</ref> Since equalizers, "adjust the amplitude of audio signals at particular frequencies," they are, "in other words, frequency-specific [[amplitude|volume]] knobs."<ref name="Hodgson">{{cite book |author=Hodgson, Jay |year=2010 |title=Understanding Records |isbn=978-1-4411-5607-5}}</ref>{{rp|73}}
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| Equalizers are used in [[recording studio]]s, [[Radio studio|broadcast studios]], and live [[sound reinforcement]] to correct the response of [[microphone]]s, [[Pickup (music technology)|instrument pick-ups]], [[loudspeakers]], and [[room acoustics|hall acoustics]].<ref name="The Audio Dictionary"/> Equalization may also be used to eliminate unwanted sounds, make certain instruments or voices more prominent, enhance particular aspects of an instrument's tone, or combat [[Audio feedback|feedback]] (howling) in a [[public address]] system.<ref name="Strong 2005 25"/><ref name="The Audio Dictionary"/> Equalizers are also used in [[music production]] to adjust the [[timbre]] of individual instruments by adjusting their frequency content and to fit individual instruments within the overall frequency spectrum of the [[audio mixing (recorded music)|mix]].<ref name="Hodgson"/>{{rp|73–74}}
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| The most common equalizers in music production are parametric, semi-parametric, graphic, peak, and program equalizers.<ref name="Hodgson"/>{{rp|74}} Graphic equalizers are often included in consumer audio equipment and [[software]] which plays music on home computers. Parametric equalizers require more expertise than graphic equalizers, and they can provide more specific compensation or alteration around a chosen frequency. This may be used in order to remove (or to create) a resonance, for instance.
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| ==Terminology==
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| [[Image:Roomcorrect-mag.png|right|thumb|The very uneven spectrum of [[white noise]] played through imperfect speakers and modified by room acoustics (top) is ''equalized'' using a [[Digital room correction|sophisticated filter using digital hardware]] (bottom). The resulting "flat" response fails, however, at 71 Hz where the original system had a null in its response which cannot be corrected.]]
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| The concept of equalization was first applied in correcting the [[frequency response]] of [[equalization#Analog telecommunications|telephone lines]] using [[Passive filter|passive]] networks; this was prior to the invention of electronic amplification. Initially equalization was used to "compensate for" (i.e. correct) the uneven frequency response of an electric system by applying a filter having the opposite response, thus restoring the [[high fidelity|fidelity]] of the [[Transmission (telecommunications)|transmission]]. A plot of the system's net frequency response would be ''flat'', as its response to all frequencies would literally be ''equal''. Hence the term "equalization."
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| Much later the concept was applied in [[audio engineering]] to adjust the frequency response in recording, reproduction, and live [[sound reinforcement system]]s. Sound engineers correct the frequency response of a sound system so that the frequency balance of the music as heard through speakers better matches the original performance picked up by a [[microphone]]. [[amplifier|Audio amplifiers]] have long had filters or controls to modify their frequency response. These are most often in the form of variable [[Bass (sound)|bass]] and [[Treble (sound)|treble]] controls (shelving filters), and switches to apply low-cut or high-cut filters for elimination of low frequency "rumble" and high frequency "hiss" respectively.
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| Graphic equalizers and other equipment developed for improving fidelity have since been used by [[recording engineer]]s to modify frequency responses for aesthetic reasons. Hence in the field of audio electronics the term "equalization" is now broadly used to describe the application of such filters regardless of intent. This broad definition therefore includes all [[linear filter]]s at the disposal of a listener or engineer.
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| A '''British EQ''' or '''British style equalizer''' is one with similar properties to those on consoles made in the UK by companies such as Amek, [[Neve Electronics|Neve]] and [[Soundcraft]]<ref name="Glossary">{{cite web|url=http://www.sweetwater.com/expert-center/glossary/t--BritishEQ |title=British EQ |publisher=Sweetwater |date=1999-12-20 |accessdate=2013-11-25}}</ref> from the 1950s through to the 1970s. Later on, as other manufacturers started to market their products, these British companies began touting their equalizers as being a cut above the rest. Today, many non-British companies such as [[Behringer]] and [[Mackie]]<ref name="Perkins">{{cite web|url=http://www.mackie.com/technology/perkinseq.html |title=Extraordinary EQ from Extraordinary Engineers |publisher=Mackie |accessdate=2013-11-25}}</ref> advertise British EQ on their equipment. A British style EQ seeks to replicate the qualities of the expensive British [[mixing console]]s.
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| ==History==
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| Audio electronic equipment evolved to incorporate filtering elements as consoles in radio stations began to be used for recording as much as broadcast. Early filters included basic bass and treble controls featuring fix frequency centers, and fixed levels of cut or boost. These filters worked over broad frequency ranges.
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| The [[Langevin (Audio)|Langevin]] Model EQ-251A was the first equalizer to use slide controls. It featured two passive equalization sections, a bass shelving filter, and a pass band filter. Each filter had switchable frequencies and used a 15-position slide switch to adjust cut or boost.<ref>{{cite web|url=http://www.gyraf.dk/schematics/Langevin_EQ251A.GIF |title=Langevin EQ-251A Schematic |author=Rick Chinn |accessdate=2013-11-25}}</ref> The first true graphic equalizer was the type 7080 developed by [[Art Davis (Audio)|Art Davis]]'s [[Cinema Engineering (Audio)|Cinema Engineering]]. It featured 6 bands with a boost or cut range of 8 [[Decibel|dB]]. It used a slide switch to adjust each band in 1 dB steps. Davis's second graphic equalizer was the [[Altec Lansing]] Model 9062A EQ. In 1967 Davis developed the first 1/3 octave variable notch filter set, the Altec-Lansing "Acousta-Voice" system.<ref>{{cite web|url=http://www.rane.com/note122.html |title=Operator Adjustable Equalizers: An Overview |publisher=[[Rane Corporation]] |author=Dennis Bohn |date=August 1997 |accessdate=2013-11-25}}</ref>
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| [[Daniel Flickinger|Daniel N. Flickinger]] introduced the first parametric equalizer in early 1971. His design leveraged the high performance op-amp of his own design, the 535 series (USPTO #3727896) to achieve filtering circuits that were before impossible. Flickinger's patent (USPTO #3752928) from early in 1971 shows the circuit topology (Figure 2.) that would come to dominate audio equalization until the present day, as well as the theoretical underpinnings of the elegant circuit.
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| Instead of slide potentiometers working on individual bands of frequency, or rotary switches, Flickinger's circuit allowed completely arbitrary selection of frequency and cut/boost level in three overlapping bands over the entire audio spectrum. Six knobs on his early EQ's would control these sweepable filters. Up to six switches were incorporated to select shelving on the high and low bands, and bypassing for any unused band for the purest signal path. His original model boasts specifications that are seldom met today.
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| Other similar designs appeared soon thereafter from [[George Massenburg]] (in 1972) and Burgess McNeal from ITI corp. In May 1972 Massenburg introduced the term ''Parametric Equalization'' in a paper presented at the 42nd convention of the [[Audio Engineering Society]].<ref>{{cite paper |url=http://www.massenburg.com/gml/downloads/parametric_paper.pdf |archiveurl=http://web.archive.org/web/20110714044154/http://www.massenburg.com/gml/downloads/parametric_paper.pdf |archivedate=2011-07-14 |title=Parametric Equalization |date=May 1872 |author=George Massenberg |author-link=George Massenberg}}</ref> Most channel equalization on [[mixing console]]s made from 1971 to the present day rely upon the designs of Flickinger, Massenburg and McNeal in either semi or fully parametric topology{{Citation needed|date=March 2011}}.
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| In the late 1990s and in the 2000s, parametric equalizers became increasingly available as [[Digital Signal Processing]] (DSP) equipment, usually in the form of plug-ins for various digital audio workstations. Standalone [[outboard gear]] versions of DSP parametric equalizers were also quickly introduced after the software versions and are typically called Digital Parametric Equalizers.
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| ==Filter types==
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| ===High and low pass filters===
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| A [[high-pass filter]] is a filter that passes higher [[audio frequency|frequencies]] well but [[attenuation|attenuates]] lower frequency components. A [[low-pass filter]] passes low-frequency components of signals while attenuating higher frequencies. In audio applications these are frequently termed "low cut" and "high cut" respectively, to emphasize their effect on the original signal. For instance, sometimes audio equipment will include a switch labeled "high cut" or described as a "hiss filter" (hiss being high frequency noise). In the times of [[phonograph]]s many stereos would include a switch to introduce a high-pass (low cut) filter, often called a "rumble filter," to eliminated [[infrasonic]] frequencies.
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| ===Shelving filter===<!--[[Shelving filter]] and similar redirects link here-->
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| While high and low pass filters are useful for removing unwanted signal above or below a set frequency, shelving filters can be used to reduce or increase signals above or below a set frequency.<ref>{{cite web |url=http://www.soundonsound.com/sos/jul01/articles/equalisers1.asp |title=Equalisers Explained |publisher=[[Sound on Sound]] |date=July 2001 |accessdate=2013-11-25}}</ref> Shelving filters are used as common tone controls (bass and treble) found in consumer audio equipment. These implement a first order response, as discussed above and provide an adjustable boost or cut to frequencies above or lower than a certain point.
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| A ''high shelf'' or "treble control" will have a frequency response ''|H(f)|'' whose square is given by:
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| : <math>|H(f)|^2 = {{1 + (f/f_z)^2} \over {1 + (f/f_p)^2}}</math>
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| where ''f<sub>p</sub>'' and ''f<sub>z</sub>'' are called the pole and zero frequencies, respectively. Turning down the treble control increases ''f<sub>z</sub>'' and decreases ''f<sub>p</sub>'' so that frequences higher than ''f<sub>p</sub>'' are attenuated. Turning up the treble control increases ''f<sub>p</sub>'' and decreases ''f<sub>z</sub>'' so that frequencies higher than ''f<sub>z</sub>'' are boosted. Setting the treble control at the center sets ''f<sub>z</sub>'' = ''f<sub>p</sub>'' so that ''|H(f)|<sup>2</sub>''=1 and the circuit has no effect. At most, the slope of the filter response in the transition region will be 6 dB per octave (thus a doubling of signal voltage and a consequent quadrupling of signal power for every doubling of frequency).
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| Similarly the response of a ''low shelf'' or "bass control" can be represented as
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| : <math>|H(f)|^2 = (f_z/f_p)^2 \; {{1 + (f/f_z)^2} \over {1 + (f/f_p)^2}}</math> .
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| In this case the inclusion of the leading factor simply indicates that the response at frequencies much higher than ''f<sub>z</sub>'' or ''f<sub>p</sub>'' is unity and that only bass frequencies are affected.<ref>{{cite book |url=http://msp.ucsd.edu/techniques/latest/book-html/node142.html |title=The Theory and Technique of Electronic Music |author=Miller Puckette |date=2006-12-30 |isbn=9789812700773}}</ref>
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| Note that a high shelve in which ''f<sub>z</sub>'' is set to infinity or a low shelve response in which ''f<sub>z</sub>'' is set to zero implements a first order low-pass or high-pass filter respectively. However usual tone controls have a more limited range, since the purpose isn't to eliminate any frequencies but only to achieve a greater balance when, for instance, the treble is lacking and the sound isn't crisp. Since the range of possible responses from shelving filters is so limited, they are considered quite inadequate for equalization tasks among audio engineers.
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| ===Graphic equalizer===<!--[[Graphic equalizer]] and similar redirects link here-->
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| [[Image:Behringer 3102 equalizer.jpg|right|400px]]
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| In the ''graphic equalizer'', the input signal is sent to a bank of [[Filter bank|filters]]. Each filter passes the portion of the signal present in its own frequency range or ''band''. The amplitude passed by each filter is adjusted using a slide control to boost or cut frequency components passed by that filter. The vertical position of each slider thus indicates the gain applied at that frequency band, so that the knobs resemble a ''graph'' of the equalizer's response plotted versus frequency.[[File:OldSchoolRack.jpeg|OldSchoolRack|thumb|right|400px|UREI graphic and parametric EQs]]
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| The number of frequency channels (and therefore each one's bandwidth) affects the cost of production and may be matched to the requirements of the intended application. A [[car audio]] equalizer might have one
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| set of controls applying the same gain to both stereo channels for convenience, with a total of five to ten frequency bands. On the other hand, an equalizer for professional [[Live sound reproduction|live sound reinforcement]] typically has some 25 to 31 bands, for more precise control of feedback problems and equalization of [[room modes]]. Such an equalizer (as shown above) is called a 1/3-octave equalizer (spoken informally as "''third-octave'' EQ") because the center frequency of its filters are spaced one third of an [[octave]] apart, three filters to an octave. Equalizers with half as many filters per octave are common where less precise control is required—this design is called a 2/3-octave equalizer.
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| ===Parametric equalizer===<!--[[Parametric equalizer]] and similar redirects link here-->
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| [[Image:Equaliser-section.jpg|thumb|100px|right|The equaliser section from the [[Audient]] ASP8024 Mixing console. The upper section has high and low shelving EQ, the lower section has fully parametric EQ.]]
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| Parametric equalizers are multi-band variable equalizers which allow users to control the three primary parameters: [[amplitude]], [[center frequency]] and [[Bandwidth (signal processing)|bandwidth]]. The amplitude of each band can be controlled, and the center frequency can be shifted, and bandwidth ("[[Q factor|Q]]") can be widened or narrowed. Parametric equalizers are capable of making much more precise adjustments to sound than other equalizers, and are commonly used in sound recording and [[Sound reinforcement system|live sound reinforcement]].
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| Parametric equalizers are also sold as standalone [[outboard gear]] units.
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| A variant of the parametric equalizer is the semi-parametric equalizer, also known as a sweepable filter. It allows users to control the amplitude and frequency, but uses a pre-set bandwidth of the center frequency. In some cases, semi-parametric equalizers allow the user to select between a wide and a narrow preset bandwidth.
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| ==Filter functions==
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| [[File:RC Series Filter (with V&I Labels).svg|thumb|frame|right|A first order low-pass (high-cut) filter implemented using only a resistor and capacitor.]]
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| The responses of [[linear filter]]s are mathematically described in terms of their [[transfer function]] or, in layman's terms, [[frequency response]]. A transfer function can be decomposed as a combination of ''first order'' responses and ''second order'' responses (implemented as so-called biquad sections). These can be described according to their so-called [[Pole-zero plot|pole]] and [[Pole-zero plot|zero]] frequencies, which are [[complex numbers]] in the case of second-order responses.
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| ===First order filters===
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| [[Image:Shelving-eq.svg|thumb|right|250px|Two first-order shelving filters: a -3dB bass cut (red), and a +9dB treble boost (blue)]]
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| A first order filter can alter the response of frequencies above and below a point. In the transition region the filter response will have a slope of up to 6 [[Decibel|dB]] per [[octave]]. The bass and treble controls in a hi-fi system are each a first order filter in which the balance of frequencies above and below a point are varied using a single knob. A special case of first order filters is a first order high-pass or low-pass filter in which the 6 dB per octave cut of low or high frequencies extends indefinitely. These are the simplest of all filters to implement individually, requiring only a capacitor and resistor.
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| ===Second order filters===
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| [[Image:Peaking-eq.svg|thumb|right|250px|Second order filter responses]]
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| Second order filters are capable of [[resonance]] (or anti-resonance) around a particular frequency. The response of a second order filter is specified not only by its frequency but its [[Q factor|Q]]; a higher Q corresponds to a sharper response (smaller bandwidth) around a particular center frequency. For instance, the red response in the accompanying image cuts frequencies around 100 Hz with a higher Q than the blue response which boosts frequencies around 1000 Hz. Higher Q's correspond to [[resonant]] behaviour in which the half-power or -3 dB bandwidth, ''BW'', is given by:
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| :<math>BW \ = \ F_0 / Q </math>
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| where ''F''<sub>0</sub> is the [[resonant]] frequency of the second order filter. ''BW'' is the bandwidth expressed in the same frequency unit that ''F''<sub>0</sub> is. Low Q filter responses (where ''Q'' < {{frac|1|2}}) are not said to be resonant and the above formula for bandwidth does not apply.
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| It is also possible to define the Q of a band-pass function as:
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| :<math>Q \ = \ \frac{\sqrt{2^N}}{2^N - 1} \ = \ \frac{1}{2 \sinh\left(\frac{\ln(2)}{2} N \right)} </math>,
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| where ''N'' is the bandwidth in octaves.
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| It should be noted that a second-order filter response with ''Q'' of less than 1/2 can be decomposed into two first-order filter functions, a low-cut and a high-cut (or boost). Of more interest are [[resonant]] filter functions which can boost (or cut) a narrow range of frequencies. In addition to specifying the center frequency ''F''<sub>0</sub> and the Q, the specification of the filter's [[Pole-zero plot|zeros]] determines how much that frequency band will be boosted (or cut). Thus a [[parametric equalizer]] section will have three controls for its center frequency ''F''<sub>0</sub>, bandwidth or Q, and the amount of boost or cut usually expressed in [[decibel|dB]].
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| The range of second-order filter functions is important because any analog filter function can be decomposed into a (usually small) number of these (plus, perhaps, simpler first order responses). These are implemented directly by each section of a parametric equalizer where they are explicitly adjusted. And each element of a graphic equalizer based on a [[filter bank]] includes one such element whose Q is not adjustable by the user.
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| == Uses ==<!--[[Mirrored equalization]] redirects directly here-->
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| In [[sound recording]], equalization is used to improve an instrument's sound or make certain instruments and sounds more prominent. For example, a [[recording engineer]] may use an equalizer to make some high-pitches in a vocal part louder while making low-pitches in a drum part quieter.<ref name="Strong 2005 25"/><ref name="The Audio Dictionary"/>
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| Equalization is commonly used to increase the 'depth' of a mix, creating the impression that some sounds in a mono or stereo mix are farther or closer than others, relatively.<ref name="Hodgson"/>{{rp|75–76}} Equalization is also commonly used to give tracks with similar frequency components complimentary spectral contours, known as '''mirrored equalization'''. Select components of parts which would otherwise compete, such as bass guitar and kick drum, are boosted in one part and cut in the other, and vice versa, so that they both stand out.<ref name="Hodgson"/>{{rp|76–77}}
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| Equalizers can correct problems posed by a room's [[acoustics]], as an auditorium will generally have an uneven frequency response especially due to [[standing waves]] and [[acoustic dampening]]. The [[frequency response]] of a room may be analyzed using a [[spectrum analyzer]] and a [[pink noise]] generator for instance. Then a graphic equalizer can be easily adjusted to compensate for the room's acoustics. Such compensation can also be applied to tweak the sound quality of a [[recording studio]] in addition to its use in live [[sound reinforcement system]]s and even home [[hi-fi]] systems.
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| During live events where signals from microphones are amplified and sent to [[Loudspeaker|speaker]] systems, equalization is not only used to "flatten" the frequency response but may also be useful in eliminating [[Audio feedback|feedback]]. When the sound produced by the speakers is picked up by a microphone, it is further reamplified; this recirculation of sound can lead to "howling" requiring the sound technician to reduce the [[gain]] for that microphone, perhaps sacrificing the contribution of a singer's voice for instance. Even at a slightly reduced gain, the feedback will still cause an unpleasant resonant sound around the frequency at which it would howl. But because the feedback is troublesome at a particular frequency, it is possible to cut the gain only around that frequency while preserving the gain at most other frequencies. This can best be done using a parametric equalizer tuned to that very frequency with its amplitude control sharply reduced. By adjusting the equalizer for a narrow bandwidth (high Q), most other frequency components will not be affected. The extreme case when the signal at the channel's center frequency is completely eliminated is known as a [[notch filter]].
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| An equalizer can be used to correct or "flatten" the frequency response of speakers rather than designing the speaker itself to be equalized. For instance, the [[Bose 901 Speaker System|Bose 901 speaker system]] doesn't use separate woofers and tweeters to cover the bass and treble frequencies, but includes 9 [[full-range]] drivers more akin to what one would find in a table radio. However this speaker system is sold with an active equalizer designed to correct the poor frequency balance of those drivers. That equalizer must be inserted into the amplifier system so that the amplified signal that is finally sent to the speakers has its response increased at the frequencies where the response of these drivers falls off, producing a high fidelity reproduction regardless.
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| [[Tone control circuit|Tone control]]s (usually designated "bass" and "treble") are simple shelving filters included in most [[hi-fi]] equipment for gross adjustment of the frequency balance. The bass control may be used, for instance, to increase the drum and bass parts at a dance party, or to reduce annoying bass sounds when listening to a person speaking. The treble control might be used to give the percussion a sharper or more "brilliant" sound, or can be used to cut such high frequencies when they have been overemphasized in the program material or simply to accommodate a listener's preference.
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| A "rumble filter" is a high pass (low cut) filter with a cutoff typically in the 20 to 40 Hz range; this is the low frequency end of [[audible range|human hearing]]. "Rumble" is a type of low frequency noise produced in record players and turntables, particularly older or low quality models. The rumble filter prevents this noise from being amplified and sent to the loudspeakers. Some cassette decks have a switchable "Subsonic Filter" feature that does the same thing for recordings.
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| A [[Audio crossover|crossover network]] is a system of filters designed to direct electrical energy separately to the [[woofer]] and [[tweeter]] of a [[2-way speaker]] system (and also to the [[mid-range speaker]] of a 3-way system). This is most often built into the speaker enclosure and hidden from the user. However in [[bi-amplification]], these filters operate on the low level audio signals, sending the low and high frequency components to separate amplifiers which connect to the woofers and tweeters respectively.
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| Equalization is used in a reciprocal manner in certain communication channels and recording technologies. The original music is passed through a particular filter to alter its frequency balance, followed by the channel or recording process. At the end of the channel or when the recording is played, a complementary filter is inserted which precisely compensates for the original filter and recovers the original waveform. For instance, FM broadcast uses a [[pre-emphasis]] filter to boost the high frequencies before transmission, and every receiver includes a matching [[de-emphasis]] filter to restore it. The [[white noise]] that is introduced by the radio is then also de-emphasized at the higher frequencies (where it is most noticeable) along with the pre-emphasized program, making the noise less audible. [[Tape recorder]]s used the same trick to reduce "tape hiss" while maintaining fidelity. On the other hand, in the production of [[Phonograph|vinyl records]], a filter is used to reduce the amplitude of low frequencies which otherwise produce large amplitudes on the tracks of a record. Then the groove can take up less physical space, fitting more music on the record. The preamp attached to the [[phono cartridge]] has a complementary filter boosting those low frequencies following the standard [[RIAA equalization]] curve.
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| == References ==
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| <!--- See http://en.wikipedia.org/wiki/Wikipedia:Footnotes on how to create references using <ref></ref> tags which will then appear here automatically -->
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| {{Reflist}}
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| ==External links==
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| {{Wiktionary|equalisation|equalization}}
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| *[http://www.audiocheck.net/engineertraining_bands_difficult.php Discriminating EQ frequencies by ear]
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| *[http://www.sengpielaudio.com/calculator-bandwidth.htm Calculator: bandwidth per octave ''<math>N</math>'' to quality factor ''<math>Q</math>'' and back]
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| *[http://www.idc.ul.ie/idcwiki/index.php/Equalisation EQ Condensed Overview]
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| *[http://www.musicdsp.org/files/Audio-EQ-Cookbook.txt Audio EQ Cookbook]
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| *[http://www.presonus.com/community/learn/equalizer-terms-and-tips PreSonus Equalizer Terms and Tips]
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| {{Music production}}
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| {{Music technology}}
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| <!--- Categories --->
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| {{DEFAULTSORT:Equalization (audio)}}
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| [[Category:Effects units]]
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| [[Category:Sound recording]]
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Very merely, organic infant food is that which is processed with no the use of artificial pesticides and/or synthetic fertilizers. While a lot of note organic food as becoming either retailer-purchased, garden grown or gathered in the wild, the correct association is certified organic foods, which are made and labeled according to strict regulatory requirements. In a quantity of nations, like the United States, the use of the word organic in the commercial industry, with out the suitable certification, is prohibited by law.
Organic child food is most typically identified in a supermarket and will be labeled accordingly. Simply because of its nature, organic child food is a lot more costly than other sorts. Processed organic baby food usually consists of only those components that are organic and has no artificial food additives. While there appear to a number of rewards to utilizing organic child food, the most frequent purpose for getting this sort of item is the general good quality. Elevated nutritional value, the absence of residues from artificial pesticides and much better taste are all good rewards of organic infant food.
Organic child food, due to the fact it is believed to be fresher, typically carries an improved taste over other baby foods. Because organic farms are little, their items are most commonly sold close to residence. Therefore, organic baby food and other merchandise function a fresher taste merely because they are fresh.
By 2003, organic food goods had been obtainable in 20,000 natural food stores and 73% of commercial grocery retailers. While many believe that organic infant food is beneficial, other people are not as specific. Some think that farming and organic fertilization might carry its personal dangers that might be passed along in organic child food.
The principal debate lies with the much better approach to manufacturing organic food. Plantar Fasciitis Reason For The Harrowing Heel Suffering 61868 [Leq] is a stately online library for additional resources about the reason for it. Is it far more wholesome to use artificial and synthetic items in food processing or all-natural fertilizer and organic farming strategies? There are both sides to any debate and the inquiries surrounding organic baby food is no distinct. There is legitimate concern over contamination and safety of organic food and goods, but an exact determination as to which side of the table is appropriate has yet to be decided.
The details in this write-up is to be used for informational purposes. If you are interested in food, you will probably need to research about What is a News Release. What Do You You Should Buy To Transform Your Kitchen? contains further concerning why to see it. It ought to not be deemed as, or utilised in conjunction with, skilled medical guidance or suggested feeding for your infant, toddler or young child. Prior to starting any food preparation involving the use of organic infant food, check with your childs physician for further information and/or a recommendation regarding the use of organic infant food as element of your childs food intake..Western Business Journal
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