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I measured the deviation of 6 Earthworks microphones.

Nuyes

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Hi guys, I'm Earthworks M30 microphone user.

I have great faith in Earthworks, but I nevertheless wanted to test it at least once.
And that dream just became a reality today.
Audio lovers in Korea heard me, they sent me their Earthworks microphones without any hesitation.


And below is a picture of Earthworks family.

_SY_1739_2 2.JPG


M23 x1, M23R x2, M30(old ver.), M30, M50






First of all, I needed a mount to hold them together fairly.

I am fully aware of how fatal the interference of the initial reflection sound is in loudspeaker/microphone measurements.
But to proceed with a measurement with one microphone stand, I need to be able to cross a total of six microphones 'completely' into the same position.
And I thought it might not be possible, so I needed a minimum safety device to measure.


So I made this mount by overlapping two 30T MDFs that have been processed by CNC.


IMG_4346.JPG

IMG_4347.JPG










And they put them all together.




IMG_4382.JPG









Also, because this was only a safety device in case the measurement failed, the measurement of each microphone was made as precise as possible using a laser.



IMG_4377.JPG
IMG_4384.JPG








Before we look at the measurement data, let's compare the calibration files (ECFs) that we received from the owners of the microphones.


00.png



The old M30 (#1) did not have a calibration file.






Now let's take a look at the data!



I measured it by replacing each of the six microphones.
But I can't believe my own microphone replacement skills.
Therefore, I repeated this one more time to find the deviation of the setting for each microphone.




01.png




The graphs on the image above represent deviations between each microphone setting.
I measured everything from M23 to M50 once and repeated this again, so it takes a total of 6 microphone replacement steps to measure M23 and return to M23.

I was thrilled shortly after I found out that it was measured more precisely than I thought.



I was disappointed because I realized that the mount with my affection soon became useless, but the accuracy of the measurement is more important than that.







02.png


This is data calculated based on the average response(with ECF) of all microphones.








03.png

This is the data calculated based on the average response of the three microphones (M23R, M50), which are universally expected to be more sophisticated.
Similarly, the ECF was applied.












04.png

This is a calculation of the response of the remaining microphones based on the response of the flagship M50.









Below is the data in the same process as above, but this time it is calculated from the responses in the default state that did not apply the ECF file provided by the manufacturer.



05.png
06.png
07.png











I'm sorry I cut you off in the middle.


I put a lot of effort into making the mount for this measurement. I also wondered how far this was valid.

This is a comparison between a one-point measurement and a mount measurement.

02.png08.png


It's never reliable data, but personally, it's touching just to have a similar shape.







Now it's time to look at the individual responses of each microphone.






M23
09.png







M23R #1
10.png











M23R #2
11.png






M30 #1 (old)
12.png








M30 #2
13.png





M50
14.png






Personally this is very interesting.









Finally, let's look at the sensitivity deviation and self-noise of each microphone.


15.png


All four other microphones except the M23 fit within +/- 0.5 dB.
(Of course, this is the data applied with the ECF file.)

I also got the data without applying the ECF file, but it was lost while organizing the file.
But I have the original, so I'll try to restore it as soon as possible.



+ I attached the missing data. (2023-01-05)






16.png




This is the sensitivity deviation of two R series microphones.
You can see that there is a difference between applying and not applying ECF files.









17.png



Finally, this is self-noise measurement data.

All microphones are calibrated using the same SPL Calibrator before measurement.





This is measured in my studio, so it cannot be measured lower than the background noise in my studio.

And I recently compared the M23R and the M30, and the self-noise of the M30 measured at this time is somewhat heterogeneous.

But this time, I compared all 6 mics in the same place at once, so I believe in this data.







Selfnoise.png




Thank you to the audio lovers in Korea who sent me the microphone.










+
I succeeded in remeasuring selfnoise with your help.
Thank you.

 
Last edited:

GNK

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You did alot effort with your measurements, but you cant compare the frequency response of the microphones if they are not at the same distance and azimuth and elevation angles to the signal source. Each microphone has to be placed at the same position as the reference microphone.
Read carefully

Also, because this was only a safety device in case the measurement failed, the measurement of each microphone was made as precise as possible using a laser.
 

G-K

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making calibrated measurements of a microphone isnt as easy as you may think
 

GNK

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@GNK look at the setup of the bundled microphones setup and then you will see that there will be an influence of the measurung.

And they put them all together.

Exactly

He said that's just a "safety device in case the measurement failed"

All the data came from one by one measurement like the picture below

Criticism has to be made after precise reading, I think :)

 

GNK

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@GNK look at the setup of the bundled microphones setup and then you will see that there will be an influence of the measurung.

And they put them all together.

You can also see that when he mentioned

I was disappointed because I realized that the mount with my affection soon became useless, but the accuracy of the measurement is more important than that.
 

GNK

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I cant see any measuring where only one microphone was included in the measurement except as it was shown in the following picture...
Simply, OP just didn't posted every picture of mics.
as long as more than one microphone is placed and they are compared the results are wrong
He placed one mic at one measurement.

I'm pretty sure you didn't read every sentences and data the OP posted.

You can do that(it's a free globe:)), but before making a critical objection I strongly recommend you read what you criticize precisely.
 

Dumdum

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I cant see any measuring where only one microphone was included in the measurement except as it was shown in the following picture...

index.php
And that is how each microphone was measured…. This has been explained several times by several members… with a laser to line them up??? Not sure if you’re ignoring people or it’s lost on translation…
 

Dumdum

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as what l can see in his measurements the microphones were bundled and not seperated for each measurements with laser alignment
Your just ignoring what we are all saying… every one of us…

or you must be correct, he went to the trouble of making up a laser alignment jig and then measured only one microphone with it… yes that must be it…
 

Dumdum

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Looked into @G-K activity history and found out that every posts he made were about pointing out potential errors from others' data.

He seems to find happiness by devaluing others.

IGNORED
Ah… one of those, got ya… nothing constructive or helpful… just rattles on about how people who go to great efforts are wasting their time… by wasting his own time with something far less constructive haha
 
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Dumdum

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@Dumdum ...and if you dont know how real measurements have to be done, then better you are quiet
The irony… it seems you miss how real measurements are done even when real measurements are done… I’m sure a moderator will be along soon enough to tidy up this thread and by thread I mean your pointless comments… ignore!
 
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Nuyes

Nuyes

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I cant see any measuring where only one microphone was included in the measurement except as it was shown in the following picture...


I'm not an expert on microphones.
I'm just one of the users who is curious about the deviation between actual use.

Measurements were performed after controlling the same position as possible on the XYZ axis, and confidence limits were cross-validated and attached to the text.

And I would like to take this opportunity to resolve the misunderstanding.
I was also misunderstood by some users of ASR that I am a person who enjoys criticizing products.

I don't know if I can feel it in my expressions and sentences, but I live in a country that doesn't use English and it's hard to use English.

Therefore, it is a big burden for me to post on ASR every time.

I have measured and reviewed more than 100 loudspeakers so far. (For Korea)
But the reason why I don't post it all on ASR is because I feel burdened to use English.

That is why I mainly post on Sointuva and other loudspeakers to raise some issues.

In fact, Kaliaudio acknowledged the problem I suggested and improved the product.

I am by no means a person who enjoys slandering anyone.
I think this is one of the possible misunderstandings in my current environment.





And Earthworks' measuring microphones are free-field microphones.

You should know that the measurement through Window gating is equivalent to Free-field unless the direct sound is distorted.
 
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MC_RME

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No need to excuse at all. Your measuring exercise was precise, detailed, and professionally executed. IMHO it was also easily understandable (except by one other person). I wish a mod would clean up the resulted mess here...
 

Blumlein 88

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his setup clearly shows that he used bundled microphone setup during his measurements and all of them will influence the soundfield, if you will believe or not. I cant see any setup where he use only one microphone comaring with one other at same position. I just look from the technical side of view and not what some hifi entusiast want to see
You missed this in the first post.

Also, because this (the six microphone bundle) was only a safety device in case the measurement failed, the measurement of each microphone was made as precise as possible using a laser.

I measured it by replacing each of the six microphones.
But I can't believe my own microphone replacement skills.
Therefore, I repeated this one more time to find the deviation of the setting for each microphone.


The OP then went on to explain his bundled rig turned out not to be useful as it interfered. He even further went on to show measurements done with each single microphone in the laser aligned position not once, but twice to show how consistent they were. Even further still, he has graphs showing the response done individually in the laser aligned position and done in the 6x bundle to show how the bundle was effecting results.

But YOU SOMEHOW MISSED ALL OF THAT WITH EVERYONE TRYING TO TELL YOU ABOUT IT!
 

SDC

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just to mention, two m23r were new ones fresh out of box for this measurement.
so this measurement does not confirm m23r infinite matching whatever.
Do they drift over time? Maybe, maybe not.
 

BDWoody

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@Dumdum ...and if you dont know how real measurements have to be done, then better you are quiet

You can have a little time off. What a silly series of posts.
 

restorer-john

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I really liked the look of the CNC mic holding rig. Looked like a kind of gatling gun to me. :)

Appreciate the massive amount of work and time that went into this comparison @Nuyes Happy New Year!
 
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