##### Teach you what is the equalizer

Equalizer is a very common professional audio equipment, the English name for the EQUALIZER, referred to as EQ. We all know the use of equalizer, but what is the equalizer in the end? Some people may blur the concept, and I will explain it.

Common equalizer there are two, one is the graphic equalizer (GRAPHIC EQUALIZER referred to as GEQ), the other is the parametric equalizer (PARAMETRIC EQUALIZER referred to as PEQ). Let's first show the equalizer:

Graphic equalizer is a kind of law according to certain rules to the whole audio 20-20000 Hz is divided into several frequency bands, each band corresponds to a level can be raised or attenuated filter circuit, according to the need for input audio The signal is individually boosted or attenuated by a specific frequency band.

Equalizer is the most common 31-band equalizer, also called 1/3 octave (1 / 3oct) equalizer. Speaking of 31 balanced, we all understand that it is the whole audio is divided into 31 bands, but the 31 paragraph how to divide? Or 1/3 octave is what the concept may be some people do **beats earphones** not understand, in fact, very simple, the so-called octave is the music said octave, 1 octave is separated by two frequencies is 1 times The relationship is, for example, 100 Hz, and the upside is 200 Hz, then the band between 100 and 200 Hz is an octave (an beats by dre studio octave on the music). The value of this octave, that is, the equalizer of each filter to adjust the size of the scale, octave value is about small, the smaller the adjustment range, the more fine, otherwise the opposite.

Understand the concept of octave, go to understand the 1/3 octave is not difficult. The so-called 1/3 octave, that is, an octave band between the band is divided into three segments, each section of the band width is 1/3 octave, such as 100-200 Hz this octave, if Divided into beats by dre cheap three paragraphs, it became 100-125,125-160,160-200 such three, so 1/3 octave of the equalizer, it is the frequency division is derived from the 100-200 Hz corresponding 100,125,160,200 Hz four frequency points, the band is divided into three sections. 20-20000 Hz, a total beats by dre sale of 10 octave, according to an octave into three segments to calculate, it was 30 balanced, with the highest frequency of 20000 Hz, it became 31.

To understand the above concepts, it is not difficult to understand 1/2 octave (15) equalization and 1 octave (7 or 9) equalization. The 15-band equalization divides an octave into two segments, while the 7-9 segment is balanced, and each filter is responsible for controlling the width of an octave.

Understand the equalizer, then understand the parametric equalizer is not difficult, what is the parametric equalizer?

We can see from the above diagram of the equalizer, the symbol divider division of each band is fixed, that is, each filter control range is fixed, and the parametric equalizer is a kind of can change the control filter Control the scope of the filter, at the same time, the filter can control the center frequency can also be set, and then level adjustment. The bandwidth of the parametric equalizer is called bandwidth (BANDWIDTH referred to as BW) control, generally used Q or oct value to represent, the bandwidth control is the most difficult part of the parametric equalizer, in fact, understand the concept of octave, It is not difficult to understand. For example, the bandwidth of the parametric equalizer is set to 1oct (Q value of about 1.4), then it means that the filter control range is about 1 octave, such as the choice of center frequency of 150 Hz, then the parameter balance The controllable frequency range is 100-200 Hz. If the bandwidth is chosen to be 0.33oct (Q is about 4.3) and the frequency is chosen to be 115 Hz, then it can control the range of about 100-130 Hz, equivalent to a 31-band balanced control range.

Contrast equalization and parametric equalization, graphical balance of the panel intuitive, intuitive operation, but because the band division is fixed, in the fine adjustment of a little lack of; parametric equilibrium operation is not intuitive, but because the frequency can be arbitrarily selected, the control range You can also choose, adjust can be fine can also be blurred, the use of very flexible.