# Q-Factor vs. Bandwith



## froggy (May 28, 2013)

Hello,

just a short question from a REW newbie:

The EQ section outputs its filter adjustments as Q-Factor.
Somtimes I need it in bandwith
(where Q-Factor=1 is a bandwith of 1.3885 octaves)

Is it possible to show these values in bandwith,
or do I need calculte it manually every time ??

greetings,

froggy


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## AudiocRaver (Jun 6, 2012)

Up to John whether or not to implement.

Here is a quick reference conversion chart.


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## JohnM (Apr 11, 2006)

There is no straightforward conversion between bandwidth and Q, equaliser filter implementations vary in how they define the bandwidth of their filters. The various formulae for bandwidth in Hz for the equalisers REW emulates are listed in the help. Easiest is probably to change the equaliser selection to one that defines bandwidth in the same way as you need, if there is one in the list.


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## froggy (May 28, 2013)

JohnM said:


> There is no straightforward conversion between bandwidth and Q, equaliser filter implementations vary in how they define the bandwidth of their filters. The various formulae for bandwidth in Hz for the equalisers REW emulates are listed in the help. Easiest is probably to change the equaliser selection to one that defines bandwidth in the same way as you need, if there is one in the list.


Hi John,

thanks for the fast answer and btw thanks for this cool program...

Of course the outputs for different filters should have the value 
which make sense for those certain filter,
even if the manufacturer implement it wrong, like here:
http://sengpielaudio.com/FilterSlope.pdf

But I meant the _generic _filter.
AFAIK there is a kind of a "standard" for audio bandwith 
which defines the -3dB mark as the "border", as mentioned here:
http://sengpielaudio.com/calculator-bandwidth.htm

so at least for the generic filter set, 
I would like to have a switch betweeen q-factor and bandwith output
(or maybe showing both side-by-side) instead of calculate it manually...

greetings,
(and keep making a very good piece of software even better 

froggy


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## JohnM (Apr 11, 2006)

froggy said:


> AFAIK there is a kind of a "standard" for audio bandwith
> which defines the -3dB mark as the "border"


That is exactly the problem unfortunately, there _isn't_ a standard for filter bandwidth. Some filter definitions use the -3 dB point to measure the bandwidth, others use the bandwidth at the half gain point - the latter approach has the advantage that the bandwidth can be specified independently of the gain or cut (-3 dB-based definitions generally have Q that changes if the gain/cut changes) and is more meaningful for filters that have less than 3 dB of gain/cut (where is the -3 dB point for a 2 dB filter?).


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## AudiocRaver (Jun 6, 2012)

As is often the case, the devil is in the details, and it is a good thing we have John around to help us keep track of those details.


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## Confocal (Feb 19, 2013)

Hello! First of all sorry for my poor English.

I would like to put here my recent experience about Q factor concept and definition. Yes, there is a little bit of confusion about the Q factor, especially on the web. But my focus is to understand the definition of Q inside the Generic Equaliser in EQ module of REW.

My experience was this: 

I was running the REW (v5) EQ module defining a Generic Equaliser because I don't have none of the predefined equalisers in REW (TMREQ, Behringer DSP1124P, …). 
I have a 1/3 oct equliser by Samson, the model D2500. So, I was interested to put the right information on the panel "EQ filters" in order to have the possibility to run the REW EQ procedure to have some suggestion about the equalisation correction for my room (considering measurement made previously).

The first little pboblem is that the Generic Equaliser has 20 filters to be defined and the D2500 (as other 1/3 oct equalisers) has 31 filters. But this was not a big issue because by defining only the first 20 filters I covered the fraquency range from 20 Hz to 1.6kHz. That was enough for me, because the most important 'issues' on my acoustic responce was in the lower range (I have a small room). 

The 'challage' was to put the right Q value in the REW Generic equaliser panel! So the question was, what's the Q value of my D2500 filters? I foud a lot of articles about this argument and honestly speaking I found a lot of bad information. So I made some measurement on the D2500 and some filter simulation in REW EQ panel. As alway the best approach is to measure and to understand!! 

In the "EQ filters" panel for my 'generic equaliser' I wrote some Q value as defined in many sites on the web (-3dB BW / central frequency or the number that is given by conversion tables so 1/3 oct BW --> Q=4.32 or as the ratio between the resonat frequency and the damping factor in the second order filter…). 
But all these definitions was wrong fot the Q to put in the REW EQ Generic equaliser to simulate my D2500 equaliser.

Infact, making a verification, always I found the Q value I wrote in the text box was not corresponding to the real frequency response of my D2500. In order to verify if the Q I selected was right or not, I made the REW measuremt of the frequency responce of my D2500 for a given frequncy (only one filter with a given gain). Of course for this measurement was not used speakers and mic, but was made directly by electrical way (REW outs in the D2500 and D2500 outs in REW). After this, I compared the measured curve of the D2500 filter at that given freqency with the shape displayed in the EQ panel activating the "filter" checkbox under the graph panel. Also I de-selected "invert filter response" in the "Graph contol" options (gear icon in the up-right of the graph window).

In this way you have the measured D2500 filter frequency response curve overlapped to the curve that REW EQ is considering as Generic Equaliser response, i.e. the resulting filter curve after I defined freq, gain and Q in the Generic Equaliser panel.

 

So, the result is this: the value for Q that fits the real frequency response of my D2500 is 3.0.
For all frequency/filter. Also, this number is constant and it is not depending by the gain of the filter. So, this is the measurement resut. But, which is the Q definition that is matching with this measured number? 
This number, 3.0, correspond to the definition of Q as the ratio between central freqency of the filter and the BW at the half value of the peak of the dB magnitude filter frequency response. It must not be confused with the -3dB response! They are very different definitions (infact, as JohnM says "...for filters that have less than 3 dB of gain/cut " the -3dB definition has not sense … "where is the -3 dB point for a 2 dB filter?")


The final check was to set a random curve on my D2500. 

 

I measured that frequency response with REW.

 

Then I set the same gain values of D2500 in the generic equaliser in the EQ panel (of course with Q=3.0).

 


I found that the measured curve (the real D2500 response) and the response curve calculated by REW (the "filters" curve in the graph of EQ module) are perfectly overlapped (see figure below).

 



I don't know, if Q=3.0 is a common number for all the 1/3 oct eqauliser, for sure by inputting Q=3.0 in REW EQ Generic Equaliser you will have the right simulation of the the Samson D2500 by REW EQ module sotware.


Despite my terrible english, I hope you understand something! ;-) By the way if you have some question I will try to answer you (depending of my english capability!!).


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## fill35U (Mar 11, 2015)

If the filter is overdamped, I could see why picking points to define bandwidth would be vague! What's the definition of bandwidth for Q<0.5?


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## Confocal (Feb 19, 2013)

Hallo fill35U!
It depends on what kind of definition you are considering for Q. When you talk about Q<0.5 which Q definition are you referring to?


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## Confocal (Feb 19, 2013)

Here below you can find the measurement results on my Samson D2500 equaliser (1/3 oct equaliser).

I made 13 measurements on the filter centered at 25 Hz. Of course, measurements are done with REW in electrical way, REW outs into D2500 and D2500 outs into REW (no speker, no mic). 

The first measure was the 0 gain curve, the other 12 measures was about the 12 positive gain positions of the cursor at 25Hz with 1dB step (I made only the measurements with the positive gain, i.e. the cursor on D2500 is moved up). See image below:

 

I calculated Q= fo/BW for each measurement. 
fo=25 Hz
Condidereing BW= f2 - f1, where f1 and f2 are the -3dB frequences from the peak value the results are these:

Gain = +12 dB, f1=22.9 Hz, f2=27.3 Hz ---> BW= 4.4 Hz ---> Q= 25 / 4.4 = 5.7
Gain = +11 dB, f1=22.7 Hz, f2=27.5 Hz ---> BW= 4.8 Hz ---> Q= 25 / 4.8 = 5.2
Gain = +10 dB, f1=22.5 Hz, f2=27.7 Hz ---> BW= 5.2 Hz ---> Q= 25 / 5.2 = 4.8
Gain = +9 dB, f1=22.1 Hz, f2=27.8 Hz ---> BW= 5.7 Hz ---> Q= 25 / 5.7 = 4.4
Gain = +8 dB, f1=22.0 Hz, f2=28.4 Hz ---> BW= 6.4 Hz ---> Q= 25 / 5.2 = 3.9
Gain = +7 dB, f1=21.7 Hz, f2=28.9 Hz ---> BW= 7.2 Hz ---> Q= 25 / 7.2 = 3.5
Gain = +6 dB, f1=21.5 Hz, f2=29.8 Hz ---> BW= 8.3 Hz ---> Q= 25 / 8.3 = 3.0
Gain = +5 dB, f1=20.8 Hz, f2=30.9 Hz ---> BW= 10.1 Hz ---> Q= 25 / 10.1 = 2.5
Gain = +4 dB, f1=18.8 Hz, f2=32.9 Hz ---> BW= 14.1 Hz ---> Q= 25 / 7.2 = 1.8
Gain = +3 dB, in this case, with the above definition is not possible to determine f1 and f2 
Gain = +2 dB, in this case, with the above definition is not possible to determine f1 and f2
Gain = +1 dB, in this case, with the above definition is not possible to determine f1 and f2 

Here below an image with the +12dB case:

 

In his post JohnM says: "...-3 dB-based definitions generally have Q that changes if the gain/cut changes". Yes, he is in right, and the measure I made confirm that: Q goes from 5.7 for +12dB curve to 1.8 for +4 dB curve.

Please, note that these are the results when we define BW as the -3dB from the peak. In my next post I will put the results using the 'half peak value' definition.


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## Confocal (Feb 19, 2013)

Please, see my previous post.
Here below you can find the results if we take another definition for Q.

I calculated Q, as in the previous case, as the ratio between center frequency and the bandwidth, Q= fo/BW, but now condidereing BW= fb - fa, where fa and fb are the frequences where the curve value is the half of the peak value.
The results are these:

Gain= +12 dB, fa=21.2 Hz, fb=29.5 Hz ---> BW= fb-fa= 8.3 Hz ---> Q= 25 / 8.3 = 3.0
Gain= +11 dB, fa=21.2 Hz, fb=29.5 Hz ---> BW= fb-fa= 8.3 Hz ---> Q= 25 / 8.3 = 3.0
Gain= +10 dB, fa=21.2 Hz, fb=29.5 Hz ---> BW= fb-fa= 8.3 Hz ---> Q= 25 / 8.3 = 3.0
Gain= + 9 dB, fa=21.0 Hz, fb=29.2 Hz ---> BW= fb-fa= 8.2 Hz ---> Q= 25 / 8.2 = 3.0
Gain= + 8 dB, fa=21.2 Hz, fb=29.5 Hz ---> BW= fb-fa= 8.3 Hz ---> Q= 25 / 8.3 = 3.0
Gain= + 7 dB, fa=21.2 Hz, fb=29.5 Hz ---> BW= fb-fa= 8.3 Hz ---> Q= 25 / 8.3 = 3.0
Gain= + 6 dB, fa=21.5 Hz, fb=29.7 Hz ---> BW= fb-fa= 8.2 Hz ---> Q= 25 / 8.2 = 3.0
Gain= + 5 dB, fa=21.5 Hz, fb=29.7 Hz ---> BW= fb-fa= 8.2 Hz ---> Q= 25 / 8.2 = 3.0
Gain= + 4 dB, fa=21.0 Hz, fb=29.2 Hz ---> BW= fb-fa= 8.2 Hz ---> Q= 25 / 8.2 = 3.0
Gain= + 3 dB, fa=21.2 Hz, fb=29.5 Hz ---> BW= fb-fa= 8.3 Hz ---> Q= 25 / 8.3 = 3.0
Gain= + 2 dB, fa=21.2 Hz, fb=29.4 Hz ---> BW= fb-fa= 8.2 Hz ---> Q= 25 / 8.2 = 3.1
Gain= + 1 dB, fa=21.4 Hz, fb=29.3 Hz ---> BW= fb-fa= 7.9 Hz ---> Q= 25 / 7.9 = 3.2

Here below you can see the graph for the case +12dB:

 

As you can see the result is always Q=3.


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## Confocal (Feb 19, 2013)

I uploaded some images in my previous post. In this way I hope it is more clear...


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## Confocal (Feb 19, 2013)

As a side effect of my measurements on Samson D2500 to understand how to simulate it in REW, there is an important discovery: the Samson D2500 is not a true GRAPHIC equalizer. It means that the D2500 NOT truly delivers the "graphic" representation of the equalization curve with the front panel sliders. This type of 'error' is caused by the NOT constant Q filter (where Q is defined as the BW at -3dB from peak). See my previous post, where the Q defined by -3dB BW goes from 5.7 to 1.8 changing the gain from +12 dB to +4dB.


This is an interesting article from Rane: http://www.rane.com/note101.html

The 'side effect' conclusion is: when I look the sliders curve on the front panel of my D2500 equalizer, this 'curve ' is not the true equalization curve that the device is performing. If you want to know the true equalization delivered by the D2500, you need to measure it with REW or to 'simulate' it with the EQ module of REW (use Generic equalizer with Q=3.0).

An example of what I am saying is the measurement I made on the D2500 response when it shows this slider positions:

 

The resulting measure is this one:

 

It is clear that at 20 Hz I'm not having -12dB as cursor says, but about -17 dB! This is because at 20Hz there is also the 'side' effect of 'some other gain' performed by the adjacent 25Hz filter.

This kind of error is more evident for low values of gain.

An other example is for this set-up:

The red curve is the position of the cursors on the front panel of Samson D2500
The yellow curve is the REW measure of the equalization curve

 

The errors, in dB, between two curves are:

f=20 Hz, cursor at -12dB, Measured value = -16.1 dB, error -4.1 dB, 
f=25 Hz, cursor at -12dB, Measured value = -18.3 dB, error -6.3 dB
f=31.5 Hz, cursor at -12dB, Measured value = -12 dB, error 0 dB
f=40 Hz, cursor at +12dB, Measured value = +10.2 dB, error -1.8 dB
f=50 Hz, cursor at +12dB, Measured value = +13.7 dB, error +1.7 dB
f=63 Hz, cursor at 0 dB, Measured value = +4.8 dB, error +4.8 dB
f=80 Hz, cursor at 0 dB, Measured value = +1.8 dB, error +1.8 dB
f=100Hz, cursor at 0 dB, Measured value = +1.1 dB, error +1.1 dB
f=125Hz, cursor at 0 dB, Measured value = +1 dB, error +1 dB
f=160Hz, cursor at 0 dB, Measured value = +1.9 dB, error +1.9 dB
f=200Hz, cursor at +2 dB, Measured value = +4.6 dB, error +2.6 dB
f=250Hz, cursor at +5 dB, Measured value = +7.7 dB, error +2.7 dB
f=315Hz, cursor at +5 dB, Measured value = +7.7 dB, error +2.7 dB
f=400Hz, cursor at +2 dB, Measured value = +4.3 dB, error +2.3 dB
f=500Hz, cursor at +2 dB, Measured value = +1.5 dB, error -0.5 dB
f=630Hz, cursor at -5 dB, Measured value = -4.7 dB, error +0.3 dB
f=800Hz, cursor at -3 dB, Measured value = -4.0 dB, error -1.0 dB
f=1000Hz, cursor at 0 dB, Measured value = -1.3 dB, error -1.3 dB
f=1250Hz, cursor at 0 dB, Measured value = -0.4 dB, error -0.4 dB

The error may be of several dB of of the same quantity of the dB desired correction!!


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## jiiteepee (Oct 20, 2013)

Confocal said:


> ...
> The resulting measure is this one:
> 
> 
> ...


You should study little how the graphic equalizer works ... try find some graphic or parametric equalizing software with plot feature (standalone or plugin (for plug-in you'd need some host software)) to see how peaking filter (this is the common filter type used in graphic EQ's) acts (google is a good friend in this but, I could suggest my own fPEQ for this which is kind of dummy parametric EQ used for to write filter commands into a file to be used with EqualizerAPO).


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## Confocal (Feb 19, 2013)

Thank you for your suggestion! I will try your software!


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## Wayne A. Pflughaupt (Apr 13, 2006)

Interesting study, Confocal. :T




Confocal said:


> Here below you can find the measurement results on my Samson D2500 equaliser (1/3 oct equaliser).
> 
> The first measure was the 0 gain curve, the other 12 measures was about the 12 positive gain positions of the cursor at 25Hz with 1dB step (I made only the measurements with the positive gain, i.e. the cursor on D2500 is moved up). See image below:


As you have discovered, the Samson D2500 is an example of a _variable Q_ equalizer, where the filter Q changes with the amount of gain applied. See below the graph below of a constant Q equalizer, the Yamaha YDP2006 digital parametric. Notice that the filter shape stays fairly constant no matter what the gain setting.










Not that variable Q equalizers are necessarily bad, they certainly have their place. They aren’t a good choice for room correction, but they are good as “tone controls,” where a change in audible sound of the speaker or instrument at a certain frequency is desired. The point is, the equalizer type needs to be chosen for desired the task.




Confocal said:


> As a side effect of my measurements on Samson D2500 to understand how to simulate it in REW, there is an important discovery: the Samson D2500 is not a true GRAPHIC equalizer. It means that the D2500 NOT truly delivers the "graphic" representation of the equalization curve with the front panel sliders.


Sure, it is a graphic equalizer. It’s merely a generic term to describe the _type_, which gives an idea of response changes when the settings are moved, as opposed to a parametric EQ or a 1/3-octave EQ like the White Instruments 4400. No one who knows how filters behave expects the sliders to give a laboratory-accurate presentation of response, and people familiar with equalizers in general know that the sliders with a good constant Q design will give a better representation of actual response changes than a variable Q.




> It is clear that at 20 Hz I'm not having -12dB as cursor says, but about -17 dB! This is because at 20Hz there is also the 'side' effect of 'some other gain' performed by the adjacent 25Hz filter.


Yes, you’re seeing the effect of “stacking” filters. This will happen with probably any equalizer.	

To be fair to the Samson, you might be expecting too much from a $200 equalizer. Take another look at your graph below, and notice how the D2500 shifts the frequency center back and forth with different gain settings. The 10 dB trace (blue-green, fourth from the top) is a bit below the 24.98 Hz center line, as is the 4 dB trace (purple, fourth from the bottom). Conversely, the 5 and 6 dB traces (red and blue) are centered above the 24.98 reference. 

Perhaps you can see why top-grade models cost 4-5+ times more than the Samson. 












> If you want to know the true equalization delivered by the D2500, you need to measure it with REW


Well said. This is true of any equalizer, no matter the make, model or cost. :T

Regards, 
Wayne


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## Confocal (Feb 19, 2013)

Thank you Wayne for your interesting answer! 



Wayne A. Pflughaupt said:


> To be fair to the Samson, you might be expecting too much from a $200 equalizer.


Maybe I was not so clear because my poor English…. I know I have a 200$ equalizer and I know which results I can expect from this device! I write some notes about the 'true' frequency response vs the graphic curve of the front panel sliders, because I think a lot of people don't know this important issue! They spend a lot of time to adjust + or -0.5 dB on the sliders and they don't know that they are making errors of several dBs compared with the sliders curve! Do you agree?! 

I agree perfectly with you that this type of equalizer (graphic equalizer) is not the best to make room correction. Graphic eq are not so useful for room equalization…the best are parametric eq as you are saying (I'm looking for something…). In the while, I have this Samson graphic equalizer, so I am trying to do the best with this device.

It's very interesting to use the EQ module in REW to have some suggestions about an equalization curve to correct 'the defects' of my room. After some diffusers, some absorbers and bass traps…now it's the moment for me to try to adjust a little bit the final frequency response with an equalizer. I have a very small room for audio production and there are a lot of interesting challenges in the frequency range under 400Hz!! 
So, the main target of my post was to tell everybody that, with some measurement, I discover the right Q number to put in the 'Generic EQ' in REW EQ module if you want to 'simulate' a Samson D2500. This value is Q=3.0. And this value matches with the 'half peak value' bandwidth definition (that is not the -3dB bandwidth).

Of course when you perform measurement, you discover always something else of interesting…but, I repeat it, the main target for me was to understand which is the best value to put in the Q 'text box' of EQ REW module to have the best modeling in REW of my Samson D2500.

Thank you again for the interesting post about the constant Q eq and the other notes! 

Regards!

PS: I recently bought a Behringer DSP 1124P from an important online store. When I received it, I was very surprised about the poor quality of this device !! onder: Ok, it's another cheap device…but the quality of the assembly and manufacture was very very poor. Inside there was a ferrite free to move because the glue that fix it, was broken. The PCB's inside was very poor, the internal wiring was fixed with other detached glue, one important cable connector was partially inserted and partially off from the PCB socket, the packaging was poor, …. at the end I returned the equalizer!!! The store apologize with me and they sent another unit. The 'new' one has the same kind of problems! I returned also that unit! Now I am looking for a parametric equalizer, but my budget is small :sad::sad: I am looking for an used Yamaha YDP2006…any suggestion for a cheap but 'honest' device?


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## Confocal (Feb 19, 2013)

Wayne A. Pflughaupt said:


> Interesting study, Confocal. :T
> 
> ...
> 
> Yes, you’re seeing the effect of “stacking” filters. This will happen with probably any equalizer.


Yes, you are in right, it is the effect of the side band of the near filters, that add 'other' gain or cut to the selected filter. But I think in the equalizers with constant Q factor this 'issue' is not so big. 

For example here there is a interesting article from Rane: http://www.rane.com/note101.html


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## Wayne A. Pflughaupt (Apr 13, 2006)

Confocal said:


> Maybe I was not so clear because my poor English…. I know I have a 200$ equalizer and I know which results I can expect from this device! I write some notes about the 'true' frequency response vs the graphic curve of the front panel sliders, because I think a lot of people don't know this important issue! They spend a lot of time to adjust + or -0.5 dB on the sliders and they don't know that they are making errors of several dBs compared with the sliders curve! Do you agree?!


Depends on the equalizer. For variable Q equalizers I’d tend to agree. A boost or cut of say 3-4 dB results in a boost of at least 1 dB or more change at the adjacent slider, even if it hasn’t been moved. (It’s not uncommon for people knowledgeable about equalizers like this to slightly adjust the adjacent sliders to counteract the variable Q effect – they even have a term for it, “equalizing the equalizer!")

However, I would expect most decent constant-Q graphic EQs to give a reasonably good visual of the change in response introduced by the sliders, at least until severe boost or cut amounts are applied (say, more than 5-6 dB). 




> So, the main target of my post was to tell everybody that, with some measurement, I discover the right Q number to put in the 'Generic EQ' in REW EQ module if you want to 'simulate' a Samson D2500. This value is Q=3.0. And this value matches with the 'half peak value' bandwidth definition (that is not the -3dB bandwidth).


Hopefully people with that equalizer will find your hard work to their benefit. :T




> PS: I recently bought a Behringer DSP 1124P from an important online store. When I received it, I was very surprised about the poor quality of this device !! onder: Ok, it's another cheap device…but the quality of the assembly and manufacture was very very poor. Inside there was a ferrite free to move because the glue that fix it, was broken. The PCB's inside was very poor, the internal wiring was fixed with other detached glue, one important cable connector was partially inserted and partially off from the PCB socket, the packaging was poor, …. at the end I returned the equalizer!!! The store apologize with me and they sent another unit. The 'new' one has the same kind of problems! I returned also that unit!


Sad to hear this. In recent years Behringers has noted on their website that they had quality-control problems for years with the Chinese factories they contracted with, so they ultimately decided to build their own factory in China to have complete control on quality. Sounds like it’s not working out. 




> Now I am looking for a parametric equalizer, but my budget is small :sad::sad: I am looking for an used Yamaha YDP2006…any suggestion for a cheap but 'honest' device?


As you said, the YDP2006. It’s as good as it gets. Lots of satisfied users here and at other Forums. I’m proud to say that I was the one who discovered this baby and introduced it to home theater enthusiasts. :T Just check my review for tips on how to make sure you get a good one, not one that’s been beat to death. You can find it in my signature.

Speaking of, would you mind if I use your variable Q graph in the review? I’m currently using one from Rane, but yours is _much_ better! I’d give you credit as the source, naturally. :T












Confocal said:


> Yes, you are in right, it is the effect of the side band of the near filters, that add 'other' gain or cut to the selected filter. But I think in the equalizers with constant Q factor this 'issue' is not so big.


Correct.




> For example here there is a interesting article from Rane: http://www.rane.com/note101.html


Yes I’ve seen it, and the other Rane articles on equalization too. All good stuff. :T

Regards, 
Wayne


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## Confocal (Feb 19, 2013)

Wayne A. Pflughaupt said:


> Speaking of, would you mind if I use your variable Q graph in the review? I’m currently using one from Rane, but yours is _much_ better! I’d give you credit as the source, naturally. :T



Of course! You can use my measured curves as you prefer! Do you need some other measurements on my D2500? Do you want the same set of curves but centered in the 'usual' 1kHz frequency? Let me know!

Bye!


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