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This has been a very frustrating experience. Ordered the UMIK-1 the first week of January and their site said they were backordered until end of the month. Still had not heard anything the first week of February and sent an email asking for a status update and no reply.

Then it arrived this week and of course my mic is affected by the calibration issue and now I have to wait until they post the corrected calibration files. The bummer is that I have been waiting like a month and a half now and cannot even use the mic and I actually have time this weekend to finally start measuring my room.

I was on the fence between this product and the Dayton, and at this point I really wish I would have gone with the Dayton USB mic. Their customer service is much more responsive and reliable.

Hopefully the new calibration files will be posted Monday but I have a suspicion it won't be that easy.
 

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cannot even use the mic
You can use the mic without the cal file, at least it will get you started, they are not that far off out of the box. You'll have a big learning curve with REW anyway. The two I have measured seem to be about a dB down at 20 Hz and have a peak of 3 dB at 10 kHz.
 

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...However can someone guide me to a fantastic simple beginners guide to eq'ing using UM1K-1 and miniDSP.
What minidsp is ideal for me.
Apparently HifiZine is being quite modest since he hasn't mentioned it but I discovered he has a very good article that might be just what you are looking for.... go here to check it out.
 

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Monomer, thanks so much for all your help, tips and links, I am starting my quest into learning the science of sound and taming it.
 

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I predict it will be quite time-consuming and complex to get my system to optimum in-room response over large area because of my particular situation (MY SITUATION: 4 subs total, two mid-bass units and two-ULF units needing first to deal with cross-over points between subs and then to get the best compromise of in-room response over 8 seated locations consisting of adjustments to gain, phasing/delay, parametric EQing, and judicious sub placements... with each change confounding the others).
Wow, 8 seated locations, that is going to be tough :) I found the "average measurements" function to be quite useful in REW. What I did was measure at my 2 main seating locations, then average their measurements into a new (third) graph, and then get REW to generate the biquads to flatten that averaged graph. This way instead of having +6dB at one seat, I end up with +3dB and -3dB at the other seat.

Also I only use cut, no boost, because I have large nulls moving even slightly to the right or left :mooooh:

It seems that unless your room is treated you could spend an eternity chasing these blasted peaks and nulls that appear and disappear at such little differences in seating position!
 

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You can use the mic without the cal file, at least it will get you started, they are not that far off out of the box. You'll have a big learning curve with REW anyway. The two I have measured seem to be about a dB down at 20 Hz and have a peak of 3 dB at 10 kHz.
Except this isn't true at all for half the mics.
Mine shows 20hz as equal to 100-200hz when my speakers are high passed at 50hz aka i have no response at all that low.
 

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Apparently the newly corrected calibration files are up (go here to read about it directly)... the bad news is there is no correction below 20Hz... sigh... they say "the supplier wasn't able to get a very reliable data" (I think that really translates into "We either forgot to or didn't bother to measure the last batch of UMIKs down that far so now there is no data record that can be spliced into the re-scaled file")... so basically these new UMIKs are no longer considered accurate down to their advertised spec of 15Hz @ +/-1dB

Yes, unfortunately that does bother me a little... if it were an auto manufacturer there'd be either rebates paid out (ala Hyundai's recent false mileage claims) or recalls set in motion to correct (re-calibrate the mic properly) for the false advertising claims... instead all we get is "the supplier wasn't able to get a very reliable data" This is beginning to make me wonder what to believe. I just hope my new calibration file is for real this time.
 

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Except this isn't true at all for half the mics.
Mine shows 20hz as equal to 100-200hz when my speakers are high passed at 50hz aka i have no response at all that low.
Hi thatsnasty, if your speakers are highpassed at 50 Hz then you would expect to see a lower reading at 20 Hz even if the mic were perfectly flat. If they show equal... well I'm confused. Perhaps you could post some graphs? At any rate, to assess the response of a microphone, it needs to be compared against a different (calibrated) microphone. The cal documentation from Earthworks and CrossSpectrum Labs includes the response of their "reference" microphone, so I believe that's how they do it as well, although of course more rigorously.
 

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Apparently HifiZine is being quite modest since he hasn't mentioned it but I discovered he has a very good article that might be just what you are looking for.... go here to check it out.
Hi monomer, thank you for the kind words :) That article will I hope still be useful, although it of course has nothing about the UMIK. It also pre-dates the REW integration with miniDSP, so just talks about manual adjustment of the filter parameters.
 

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Hi,
as already known, minidsp has been published the new calibration files for SN#7000190-7000439.
Ok here is the comparsion of these 250 cal-files. Look here for the "older ones".

Now they look more similar to calibration files (see 500 calibrations of different mics: http://www.hifi-selbstbau.de/index.php?option=com_content&view=article&id=367)
Four mics are a little bit out of range (267, 342, 344 and 406).

CF-UMIC-190-439.jpg

What is very interesting all files have zero dB at 990 and 1002 Hz.
CF-UMIC-Zero-dB.png

Edit: Last Friday my UMIK arrived. It has been pending with customs 4 or 5 days. So the delivery duration was about a week. There was no tax but importation VAT of 19% ~ 15 Euro.
 

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dezibel... big thanks for doing that. Makes me feel better about things now that the new calibration files are more normal looking.
...What is very interesting all files have zero dB at 990 and 1002 Hz...
I'm assuming all these mics were normalized at 1kHz (which was another step they failed to do on the original calibration files). My new calibration file has values totally different from the original one I downloaded... must have been due to the normalization process. They definitely look a LOT better now anyway... I believe (probably on Thursday) I'll compare my UMIK with its new calibration file to my EMM-6 with its calibration file and see how closely they both agree. If I'd known that the calibration file was going to just end at 20Hz, I would not have bothered to purchase this UMIK as my EMM-6 already does that.... sigh. It's bad when the specs change AFTER you purchase.
 

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monomer have you planned to compare the two mics with a measurement or just compare the cal-files?
If you make a measurement I'm very nosey about the results.
What do you want to measure at these low frequency under 20 Hz?

Edit: miniDSP has updated the UMIK-1 datasheet (20 HZ- 20 kHz)
 

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I was thinking about nearfield measurement of one of my subs... most likely the Rythmik (has a spec of 14Hz -3dB) also maybe a system measurement taken in our basement theater.

Here is one I took last month using the EMM-6 to get an idea of the in-room response of a new sub I'd just built.
 

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I've been following this thread for a month, and I'm still not sure if I should pick up this mic or not. If I wanted to buy a mic tomorrow, should I get this? Or maybe an SPL meter and an EMM6 or ECM8000 instead?
 

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dezibel... big thanks for doing that. Makes me feel better about things now that the new calibration files are more normal looking. I'm assuming all these mics were normalized at 1kHz (which was another step they failed to do on the original calibration files). My new calibration file has values totally different from the original one I downloaded... must have been due to the normalization process. They definitely look a LOT better now anyway... I believe (probably on Thursday) I'll compare my UMIK with its new calibration file to my EMM-6 with its calibration file and see how closely they both agree. If I'd known that the calibration file was going to just end at 20Hz, I would not have bothered to purchase this UMIK as my EMM-6 already does that.... sigh.It's ba when the specs change AFTER you purchase.
Matter of interest where was your EMM-6 calibrated?
 

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Sorry if this is a little off topic but can somebody tell me where to point the mic when measuring. Ceiling, at speaker being measured or in the middle of the front wall between speakers. All at ear level of coarse.
 

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Matter of interest where was your EMM-6 calibrated?
Bought it from PartsExpress and it has its own downloadable calibration file keyed to the mic's serial number... very similar to the way this UMIK is sold. Sadly its calibration file too only goes down to 20Hz even though its response range is advertised as being 18Hz to 20kHz... thus it is also misleading. Its only $48 but after purchasing a pre-amp it comes to about the same money in the end.
 

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I've been following this thread for a month, and I'm still not sure if I should pick up this mic or not. If I wanted to buy a mic tomorrow, should I get this? Or maybe an SPL meter and an EMM6 or ECM8000 instead?
I'm not sure anybody could or should tell you which mic to get... it would depend upon so many personal factors... such as budget, needs, requirements, function, expectations, etc. I think most here are purchasing the UMIK simply for the ease of integration with REW. For anyone new to REW the UMIK might represent the least frustrating way to get up and running.
 

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...miniDSP has updated the UMIK-1 datasheet (20 HZ- 20 kHz)
They also tightened up the tolerance from "+/-1dB" bringing it down to a more reliable "+/- .5dB with calibration file" almost as if to insinuate that they now have better reliability and confidence in their measurements, yet I was told just this morning that anything below 20Hz was no longer considered reliable. Still as of this moment, the first batch of UMIKs are showing calibration files that go all the way down to 4.6Hz, and yet apparently this latest batch of UMIKs does not have calibration files that can be trusted below 20Hz even with the supposedly greater accuracy now being claimed at and above 20Hz. I'm sensing some contradictions... I'm getting a feeling that some of the explanations that were given out by miniDSP are possibly not the complete story.
 
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