# question regarding EQ Wizard



## Mohammad (Jan 13, 2010)

What if I do measurements simply with the speakers already connected to my PC and with the simple mic that can be used for internet conversation?? will the results be very different or at least it will give some indications??


I hope I can hear some detailed answers. I saw the diagram for connection in one thread.

I tried to make some measurements by the simple mic and speakers which already connected to the PC and the result was a little ok.


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

> What if I do measurements simply with the speakers already connected to my PC and with the simple mic that can be used for internet conversation?? will the results be very different or at least it will give some indications??


 The results you get will be a combination of the speaker’s response, plus that of the mic. If you want accurate speaker measurements, a calibration file must be added to REW for the mic. It would compensate for (and remove from the equation) the measurement mic’s deviations from flat response.

Regards,
Wayne


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## Mohammad (Jan 13, 2010)

thank you, this is very informative reply for me, but, can I ask you for a favor? how can I add the calibration file to REW? also, is there any more information regarding how to calibrate and for general use?? I have some videos by Mr. Ethan Winer I saw on the youtube, do you have more?

you can say I am still alphabet learner on REW because my job is how to do design for sound proofing and treatment and my knowledge in measurement is very weak, therefore, I will be grateful for any additional info.


thank you,


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

> how can I add the calibration file to REW?


I would expect that the “conversation” mic you have is unsuitable for any kind of measurement, but you’d have to first create a calibration file for it, save it to your REW Folder, then load the file into REW from the “Settings” window, “Mic/Meter” tab. See this post for info on how to create a calibration file for a mic.

Regards,
Wayne


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## Mohammad (Jan 13, 2010)

thanks Wayne, 
I have read the thread you sent me, it was beneficial. I will purchase omni-directional mic and see what I can do for the calibration, and if i need anything :help: i will ask you.  

thank you very much,


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## Mohammad (Jan 13, 2010)

Hello Wayne,

I have read the article you sent me regarding MIC calibration and other things. to be honest, as a mechanical engineer I feel like a partially blind when read some technical articles with some unclear words to me like, BFD, fire wire connection and so many other words. I would not say that I need a total course in electronic engineering, but I just want to have a good connection to resume measuring by REW. I went to the SHURE agent in my country and asked about MICs sensitive and can be connected to PC. he only has KSM9 [switchable cardioid]. but he told me it needs preamp before connection to PC. price is about 800 Euros for MIC and 900 Euros for preamp. I became very disturbed, matters are mess in my mind. therefore and before I ask about connection, calibration and measurements I need to ask about needed hardware. I only have simple two speakers and subwoofer [2.1] and simple sound card with MIC in, port for subwoofer and another two ports. I dont know how to attach photos to show you the system I have. now please tell me if any of the available system can help me or not. also, please tell me all hardwares i need in name, like, speakers, mic, preamp equalizers, assuming that i have nothing???
I am sorry for asking a spoon feeding info but I really need to build information in this section.

thank you,


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

This post will tell you how to upload pictures to your posts. It’s the same process as posting graphs.

The BFD is the Behringer Feedback Destroyer equalizer; people typically use it to equalize their subwoofer.

As far as the hardware needed to operate REW, you’re going to need an outboard USB soundcard; it sounds like yours won’t work since it only has a mic input. 

The Behringer UCA202 sound card mic should work for you; people have had success using it with Windows XP and Windows 7. If you have a different operating system, you should search the interned for reviews, to make sure it is compatible with your operating system. [url =http://www.hometheatershack.com/forums/rew-forum/28299-first-time-rew-plot-2.html#post262011]This post[/url] will tell you what to look for in a review. If you live in Europe, you should be able to get the UCA for 36 Euros. If the UCA202 is not compatible with your operating system, it should not be hard to find another one that is.

If you want to take full range measurements, you’ll need a mic like the Behringer ECM8000, and a pre-amp like the Behringer Xenyx 502. You should be able to purchase the 502 pre-amp for 60 Euros and the ECM8000 mic for 73 Euros. 

The mic will need a calibration file to use with REW; we have a generic file that you can download  here.

A SPL meter is nice to have, but you can work REW without it if need be.

Regards,
Wayne


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## Mohammad (Jan 13, 2010)

OK Wayne, 

I will fetch those tools; sound card, preamp and mic. I am not in Europe I am in Jordan [Middle East]. I will search for the agent who sells those products. if don't find I will check for another brands or request by courier. but what for the speakers? you can see in the pictures that i have two small pic and subwoofer, is it ok??

for the SPL meter i have one but i dont think it can be connected to the pc, it is an old one. 

finally, if I want to make the measurements for already built control room, such that the speaker are already located and fixed, can i connect them to the PC instead of my own speakers and subwoofer?? 


thank you,


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

> for the SPL meter i have one but i dont think it can be connected to the pc, it is an old one.


If you’re using a mic like the ECM8000, there is no need to connect the SPL meter to the PC.




> finally, if I want to make the measurements for already built control room, such that the speaker are already located and fixed, can i connect them to the PC instead of my own speakers and subwoofer??


The soundcard has a standard RCA audio output that will connect to the amplifier your speakers are connected to. You might want to review the connection diagrams in the link below.

REW Cabling and Connection Basics

Regards,
Wayne


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## Mohammad (Jan 13, 2010)

thank you Wayne,

I will do my homework and show you results.

thanks,


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