# Help with UMM-6 REW HDMI frequency response



## Deepstage (Jan 12, 2012)

I just got my UMM-6 last week. I've read all the tutorials and set it up on my laptop using HDMI out to my XMC-1 for measuring frequency response of my new drivers Usher 8945A and Tymphany xt25tg30-04. 

The measurements look good up til after 5k or so and really by 10k the response is steadily declining to 20k where it's about 10-15db down. I've tried a 3 laptops and my home pc and get the same results. NO processing is active in the XMC-1 and I have everything set correctly in preferences as per the guidelines. I've also tried the ASIO4all drivers with pretty much the same result. 

Has any used this mic with a laptop and standard intel soundcard successfully? I've got a call into tech service at Parts Express and am awaiting a return call from them after they check with the folks at Dayton. 

I've posted over on the PE forums but no suggestions have solved the problem yet. Ranging from simple things like calibration file loaded to scrapping the laptop sound card and getting a stand alone sound card. 

I've also tried it with ARTA and get the same response. The thing is, when I check various frequencies at say 1k, 5k, 10k, 20k with a sine wave and compare them to a radio shack digital spl meter, I also get a falling response as the frequency increases. So I can't completely rule out the computer soundcard or some setting. 

If I have to return this mic and get a calibrate one from Cross Spectrum, I have no problem with that. Whether it be a UMM-6 or a UMIK. 

I know people have used the USB mics with REW successfully so I have a hard time believing I have to buy more hardware to get a decent reading. 

Any input from users with these mics and experience getting them reading correctly would be appreciated!

Paul

John, hopefully you will see this and have some advice on what to check.


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

Dayton’s calibration files are known to be practically worthless - see here.

Have you tried measuring a different speaker? That would give you some basis of comparison.

Regards, 
Wayne


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## Deepstage (Jan 12, 2012)

Wayne, yes I have. I've tried measuring my existing speakers and multiple other drivers with the same results. 

I have read that about their cal files before and that's what gives me pause.


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