# recommended USB microphone for REW



## riingenr (Oct 6, 2009)

Hi, we are going to use REW to setup general PA and conference room audio systems. Our laptops have an audio jack that is both input and output(lame!) depending on pc settings. Since we want to use the test patern outputs within REW I need this jack to be an output. So....can anyone recommend a USB mic and is it even recommended? -Rob


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## brucek (Apr 11, 2006)

> So....can anyone recommend a USB mic and is it even recommended?


No, REW won't operate with a USB mic. For laptops, most people require an external USB soundcard that has a line-in and a line-out, or a line-out and a mic preamp for condenser microphones.

brucek


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## riingenr (Oct 6, 2009)

thanks Bruce, I'll look into the external USB soundcards. 
or do you think I should use my laptops mic input connector for REW and get an external white noise generator?


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## brucek (Apr 11, 2006)

> use my laptops mic input connector for REW


No, the mic-in jacks on laptops are not suitable for use with REW.

brucek


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## jlohl (Jun 6, 2007)

> REW won't operate with a USB mic


I have used this one successfully with B&K4006, KlarkTeknik measurement mics, ecm8000 and various softs (REW, R+D, ARTA,...) :
http://www.mxlmics.com/products/USB/MicMate_Classic/MicMate_Classic.html
I also checked its frequency response which was OK for acoustic measurements (+-0.5dB 30 to 15kHz, if I remember)


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## riingenr (Oct 6, 2009)

Thanks, the Mic Mate is pretty interesting. So you DID get this to work well with REW?


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## JohnM (Apr 11, 2006)

You can use a USB mic, but the same caveats apply as when using a laptop or desktop mic input: the frequency response may be optimised for voice use (and so roll off at LF and perhaps at HF also) and the signal/noise performance may be poor. Without something to compare the results against it is hard to know whether a mic input is useful or not, though on a USB mic the frequency response (or at least its extents) should be in the spec somewhere.


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## jlohl (Jun 6, 2007)

> So you DID get this to work well with REW?


yes, Micmate works fine with REW



> on a USB mic the frequency response should be in the spec


the Micmate and equivalent products are not usb mics : it's just an external soundboard with phantom power supply. Before using the Micmate, I measured the frequency response for my calibration : it was good enough for acoustic measurements. So the measurement quality depends only on the mic you use.


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## brucek (Apr 11, 2006)

> So the measurement quality depends only on the mic you use.


How are you able to do a soundcard calibration when using USB as the input?

brucek


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## alcalae (Jun 1, 2009)

"So the measurement quality depends only on the mic you use."

It's probably been told before but
Why can't i use, for example, an AKG perception 100, a MXL 2001 or overhead mics with the REW software instead of those pencil shaped measuring mic?
Aren't these flat enough?
What's the difference?


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## brucek (Apr 11, 2006)

> Aren't these flat enough?
> What's the difference?


Use any mic you wish as long as you have a mic calibration file that REW can use.

brucek


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## jlohl (Jun 6, 2007)

> How are you able to do a soundcard calibration when using USB as the input?


I connected a measurement generator (Audio Precision, Prism or equivalent) on the input of the mixmate and recorded a wav file. Then I analysed this file (frequency response, distortion). This response added to the cal file of the mic itself gives me the global cal file to use.


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## JohnM (Apr 11, 2006)

alcalae said:


> Why can't i use, for example, an AKG perception 100, a MXL 2001 or overhead mics with the REW software instead of those pencil shaped measuring mic?


The main difference between a measurement mic and a studio mic is usually the polar response. Measurement mics are omnidirectional, which allows them to capture the whole soundfield and makes them (fairly) insensitive to orientation. Studio mics are typically directional to varying degrees (cardiod, commonly) which means measurements taken with them will be very sensitive to the direction the mic is pointed and the contributions of the room coming from other directions will be attenuated.


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## BowerR64 (Nov 4, 2009)

Wouldnt you want a microphone that emilates a persons ears? They have these dummy heads that have testing microhpnes in them for headphone testing i would think somthign similar to this would be ideal/ Even if its just 2 microphones in mono.


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## MatrixDweller (Jul 24, 2007)

I think with REW and general room acoustics you are looking to measure how the sound is behaving in the room and not how you perceive it with your ears. You could then make mathematical assumptions geared towards how it would be heard. It would be much harder, if not impossible, to do it the other way around with a directional mic.


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## BowerR64 (Nov 4, 2009)

MatrixDweller said:


> I think with REW and general room acoustics you are looking to measure how the sound is behaving in the room and not how you perceive it with your ears. You could then make mathematical assumptions geared towards how it would be heard. It would be much harder, if not impossible, to do it the other way around with a directional mic.


Yeah maybe thats being a little to critical?

Somthing like that might be better for the full range speakers? *shrugs*


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## glaufman (Nov 25, 2007)

BowerR64 said:


> Wouldnt you want a microphone that emilates a persons ears? They have these dummy heads that have testing microhpnes in them for headphone testing i would think somthign similar to this would be ideal/ Even if its just 2 microphones in mono.


Not really. Everyone hears slightly differently. If only because everyone's had different events in their lives that have damaged or not their hearing accordingly. If the idea is, first and foremost, accuracy, you want the test equipment to be as neutral as possible. Ears, are anything but.

It sounds like you're wandering (unintentionally) towards the old loudness switches, that tried to contour the FR to mimic the the equal loudness curves... not necessarily a bad goal, but not exactly easy to implement...


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## nigel_pearson_au (Dec 10, 2009)

Sorry if this is off topic for the thread.


I have been unable to get an MXL MicMate working with a Mac (10.6). (REW 4 or 5)

I set "USB Audio CODEC" as the default input in "Audio MIDI Setup" and start REW, then set input default device, but levels are always zero. Have tried left & right, 44 & 48K, et c.


The MicMate and microphone work well in FuzzMeasure, but they allow direct selection of the device in the Preferences. REW only lists line, mic and default.

It must be something really stupid, but I am stumped!


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

Hi Nigel, welcome to the Forum. Unfortunately, REW won’t work with a USB mic pre amp like that. You’ll need a full USB audio interface with line inputs and outputs, such as Tascam’s US122L or M-Audio’s Mobile Pre.

Regards,
Wayne


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## nigel_pearson_au (Dec 10, 2009)

OK. Thanks. More stuff to buy :-(

Although, earlier in this thread, jlohl claimed that this device _did_ work. Maybe I should ask him how?


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## JohnM (Apr 11, 2006)

You could use it, but there is no way to calibrate the response so you would end up somewhat in the dark as to the accuracy of what you would measure.


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

nigel_pearson_au said:


> OK. Thanks. More stuff to buy :-( Although, earlier in this thread, jlohl claimed that this device _did_ work. Maybe I should ask him how?


No need, he described in Post #12 how he did it:




jlohl said:


> I connected a measurement generator (Audio Precision, Prism or equivalent) on the input of the mixmate and recorded a wav file. Then I analysed this file (frequency response, distortion). This response added to the cal file of the mic itself gives me the global cal file to use.


Regards,
Wayne


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## nigel_pearson_au (Dec 10, 2009)

Sadly, still confused. Post 12 tells me how he calibrated for that device, but not how he got REW to see it as an input?


P.S. Is there a list of "supported" USB/FireWire gizmos somewhere?


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

nigel_pearson_au said:


> Sadly, still confused. Post 12 tells me how he calibrated for that device, but not how he got REW to see it as an input?


Drivers? Or perhaps the Mixmate just works better with his OS than with yours. Have you done any research to see if there are any compatiblity issues between it and your OS? Are there any updated drivers to download from the manufacturer's website?




> P.S. Is there a list of "supported" USB/FireWire gizmos somewhere?


Sorry, no. There are just too many soundcards and stuff out there, both past and present, for us to evaluate. The best you can do is search our Forum to see if other people have successfully used it.

Regards,
Wayne


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