MiniDSP UMIK X USB Multichannel Microphone Array Review

[hardisj]

Up for review is the MiniDSP UMIK X USB Multichannel Microphone Array. You can read more about it here: https://www.minidsp.com/products/acoustic-measurement/umik-x-multichannel-mic

The big benefit here is being able to measure and equalize the response of multiple spaces at the same time while also having an average of each space in real-time. Which sure beats waving a mic around to capture the response, then EQ'ing, then waving the mic around and continuing that process until you get the desired response.

 

[Juhazi]

Do you think that the grid is wide enough? When I wave my arm around the diameter is 1,2m ...

 

[hardisj]

Do you think that the grid is wide enough? When I wave my arm around the diameter is 1,2m ...

Well, let me ask you this.... why do you think you need to wave it around 1.2m?

Even something like DIRAC - when measuring a single listening position - is only in the neighborhood of a 0.30 - 0.50 meters or so.*


*BTW, I had to convert from feet to meters. When is the rest of the world going to get with the program and switch to standard units like the US?!

 

[hardisj]

Truth be told, if I were measuring these in a single headspace area, I would rig them up so that two or three are together and cover a box type shape. That way it is always repeatable, too.

 

[Jdunk54nl]

Truth be told, if I were measuring these in a single headspace area, I would rig them up so that two or three are together and cover a box type shape. That way it is always repeatable, too.

That is where I see some use, having one going right, one left, one up, then one forward (towards the front speakers and/or Windshield)

On the other hand, unless REW gets an upgrade to view real time impulse, phase, and FR much like systune or smaart, I don't see the over all benefit in this other than what you noted. Not enough difference/time using a single microphone (MMM) and pink noise.

I think spending the money on smaart di v2 which is like $600 and a daytom emm6 and a focusrite 2i2 would be better to get that real time phase/impulse/frequency independent of source (music, pink noise, whatever you want)

I am tempted to buy the pro license for REW because right now, you get any pro upgrade for the future, will that always be the case?

 

[Blumlein 88]

Thanks for this review Erin. I can see why this one was more trouble to bring together.

I wonder if the electrets directionality mentioned are why they have a flatter response vs the Umik-1?

I also noticed early in the video these were just circuit board material, and it concerned me if they were too fragile. Which you later covered in the video.

When I first saw the Umik X, I expected they'd be using some software processing to test results from different directions. You can look at one direction and ignore others with such an array if you handle it right. Do you know if this is something they plan on doing in the future?

 

[Valentin R]

Can the umic x give individual response for every mic or set or is it always an average of all modules connected

 

[dominikz]

Up for review is the MiniDSP UMIK X USB Multichannel Microphone Array. You can read more about it here: https://www.minidsp.com/products/acoustic-measurement/umik-x-multichannel-mic

The big benefit here is being able to measure and equalize the response of multiple spaces at the same time while also having an average of each space in real-time. Which sure beats waving a mic around to capture the response, then EQ'ing, then waving the mic around and continuing that process until you get the desired response.

Very interesting review, thanks!

Regarding HF response drop you saw with single mic MMM - I suspect the reason might have to do with microphone orientation. I noticed in my measurements that >10Hz range can be affected depending on how I point the microphone and I believe the reason for this is increase of directivity and related loss of off-axis sensitivity usual to omnidirectional microphones as we go up in frequency.

E.g. these are the frequency response / calibration curves of my Cross-Spectrum labs calibrated Dayton Audio EMM-6 for 3 incidence angles:

As you see, at 90 degrees off-axis sensitivity drops by around -6,5dB at 20kHz (the drop starts gradually from about 2kHz).

So if we point the microphone straight to the source, the direct sound and front wall reflection will be captured with relatively flat spectrum while all the other reflections will be captured with some HF attenuation (as they will be picked up off-axis by the mic) - resulting in less total HF content in the recorded signal.

If we however point the mic to the ceiling (and use the 90 degree calibration curve), direct sound and all side reflections will be captured with the same, flat spectrum. Ceiling reflection will on the other hand be captured with some HF boost (due to mic's flat on-axis response and the HF boost applied by the correction curve). Floor reflection may still be captured with some HF attenuation though - due to >90 degree incidence angle vs microphone axis.

EDIT: Of course, my rooms are pretty live - I guess the impact in a treated / dead room would be much smaller than what I usually see.

Anyway, just a thought - perhaps it's worth a try!

 

[Juhazi]

I'm waving my arm when I do MMM/RTA measurement around my spot.

https://www.soundimports.eu/en/mini...gXzCQrsI1r2MP7zD4f-g0NDlkF8FuoIRoCyqUQAvD_BwE

UMIK-X isn't obviously trying to replicate MMM with it's small grid, but only when "up to four arrays" are applied. A single array gives some spatial averaging obviously better than a single monopole/cardioid average mic like UMIK-1, but I don't see the need for me of purchasing -X to support -1 that I have. UMIK-1 has two calibration files, for axial and 90deg tilt.

 

[ernestcarl]

The difference between 0° and 90° are small enough in my own room/space with MMM that I don't really care too much either way.

Perhaps in a bigger room with longer distances, the difference would be more readily apparent.


For single point measurements where one may want to get additional information like the phase and impulse, I almost never use the magnitude response in it for EQing -- unless averaged spatially a little -- although, preferably by a lot more data points.

I want to get an array of UMIK-X just for the sake of convenience, but I know I'm clumsy enough that I doubt it will last me as long as a regular omni mic would.

 

[Dumdum]

Can the umic x give individual response for every mic or set or is it always an average of all modules connected

To answer this, in smaart I can see individual mics and make an average of any of the eight… in room eq wizard pro (you get the multi mic license free with the umik-x) I can use from and to in a range, so I can use 1-4, 1-8, 3-6 but not for example 3,4,7 and 8, just as many or as few consecutive mics as required

I will be using the array for tuning a car audio dsp with it positioned as a 4 wide x 2 mic array around the headrest location

 

[Dumdum]

As a further technical help… I had issues with both arrays linked powering up, both would power up being the first in the chain, but the second daisy chained one wouldnt…

If fixed to my modified metal bracket…

I had re drilled the supplied bracket so the arrays were horizontally oriented and closer together as I only want to measure a single headspace in a vehicle…

it turns out you need the two arrays to be electrically isolated from one another, I had drilled two new holes, cleaned them with a countersink of swarf and this exposed aluminium on the cast bracket

when I screwed both arrays to the metal bracket I presume it linked the two electrically and prevented them getting the correct address and powering up properly (blue lights on both arrays need to be lit for them to work correctly…

so now I have used some foam tape on the metal bracket and also two nylon cable ties instead of the knurled screws supplied, this isolates the two arrays and allows them to get identified and power up correctly They weigh next to nothing so nylon cable ties are plenty strong enough!

you can see below the powder coated holes and my shiny exposed aluminium freshly drilled holes…

I have informed mini dsp and we shall see if they isolate the screw mounting fixings or change the design somehow

 

[Dumdum]

I am also 3D printing a mic sized tube so I can use my isemcon mount to hole the array in the centre of the headrest at the correct height for my ears

an m10 bolt (it’s an imperial 3/8 thread, but the M10 goes in far enough and I’ve made the tube the correct length so it bites just as it starts to get tight) through a 19mm diameter tube will serve as a good mic replicator to fit in my bracket I’ll post pics once it’s done!

 

[Dumdum]

19mm tube printed and attached to the supplied bracket

 

[Dumdum]

So for all those who take the plunge mini dsp have been able to replicate a fault I managed to find, simple fix, but should I have to unsolder things on a mic array that was £500?

“
Hi Adam,

A quick update on the UMIK-X board. Our engineers have come up with a simple fix that can solve the "metal grounding" problem. You can simply remove the TWO resistors circled in the attachments and you should be able to use the metal mount without any compromise. Simply use a solder gun to take them out with caution and it should do the job. Thank you!

Hoping this info helps and feel free to contact us if you have further questions.

Best Regards
miniDSP DevTeam”

not really ideal and if anyone else tightens the grub screws up and cuts the powder coat they will also need to be modifying there umik array also

 

[MarkI]

So I have sent a request to MiniDSP about my new Umik-X had stopped working. Just got the thing, worked great. used it a few times, in fact I never put it away.
A few nights ago I hooked it up and only one mic lit up? not all four. Tried every thing. Out of frustration I thought I’d post what was going on here.

Here is what was sent and got back.

I recently purchased see Umik-X, have used it a few times. Been very careful. All of a sudden only one mic is lighting up. I’ve tried different power supplies. One was not included in the box. It only seems to light up one of the four microphones. I have also tried installing new firmware in the USB-A2B .I believe it took the UMIK-X_V1.9a_up.bin ????

Thank you,

Hi Mark,

This is odd indeed.. Can you maybe send us a couple of pictures of how it's wired up together with the symptoms?
The latest firmware will be found on the user downloads section. You can define it as 16ch device.

Hoping this info helps and feel free to contact us if you have further questions.

Best Regards
miniDSP DevTeam

Just minutes after sending the request I got that and sent picks with a longer explanation. Herd nothing?

So today I sent out another request, hope something happens. $850 used it twice.

Hello,

I have not heard back from initial reply and my response.

On 9/5/22 I ordered the UMA4 A2B Mic modules 4 x UMA4 modules (16ch)
Add a Microphone Tripod: Yes (4 x Tripods) order number 1PF3094363

First off there was no power supply included.

I have read the user manual multiple times. Before I started using it and since the problem arose. I do understand how to hook up and wire the modules in series. I’ve used the set up a few times. In fact it’s never been put away just put to the side of my theater room. And has worked fine.

A few nights ago I hooked up the 4 Mic modules to USB-A2B interface. Applied power, Only the first module/mic turned on, not the other 3. I have tested all of them and they all work, Only 1. If I ad 2 or more modules again only the first one turns on. I have tried different power supplies and so on.

I downloaded the current Firmware UMIK-X_fw_v1_9a.zip and have installed it several times with no change to the problem. At this point I am certain that it is the USB-A2B interface.

Can you please send me the power adapter/supply and a replacement USB-A2B interface.