"Note that this test did not attempt to evaluate anything other than raw frequency response. We didn't measure distortion, off-axis response, maximum SPL capability, build quality, or residual noise."

works great for me.
 

bapu
"Note that this test did not attempt to evaluate anything other than raw frequency response. We didn't measure distortion, off-axis response, maximum SPL capability, build quality, or residual noise."

:-) Glad to see someone read the article.
 
I guess he didn't realize he had to explain that none of those qualities seem to have much consequence in the context of making room measurements.
 
distortion: Hopefully it is so low that it isn't discernible when the mic encounters <90dBSPL
 
off-axis response: The mics mentioned are all omni pattern small diaphragm mics, meaning that they purportedly have very even off axis response. No omni mic has perfectly even off axis response and all have some fall off at the highest frequencies. The basic design of pressure sensitive omni capsules tends to make them perform more similarly "off axis" than not. The pressure gradient cardiod type mics, on the other hand have wildly differing off axis response characteristics.
 
maximum SPL capability: Again, the context of room testing suggests that all the mics will have 20, 30 maybe 40dB of head room before the MaxSPL is approached. As a reminder, the MaxSPL rating of a microphone is related to some defined level of distortion at it's output.
 
build quality: The mics either work ok or they don't. For example dbx has two mics which they sell as Real Time Analysis mics. One is made of "sturdy metal" and the other is made of "plastic". dbx advises that either work fine with the dbx RTA systems.
 
residual noise: This quality could be a possible concern, but I can't remember the last time I heard residual noise on any of my contemporary design mics. I can certainly turn up the gain until I find the noise floor, but at nominal gain levels it hardly seems to be a concern. Some of my vintage, or vintage style mics do have residual noise that sometimes shows up during normal use.
 
 
So anyways... just pointing this out for anyone who didn't read the article.
 
 
One thing I found very interesting is how similar all the mics are. I think this is because they are all omni mics and omni mics are inherently flat and even in their response.
 
When I compare the similarities reported in the article to the idea that professional mic calibration file services provide you with a database that represents your mic's specific frequency response it makes me wonder how much variance those professional service providers actually see from mic to mic.

just for fun,
i used my shure KSM44 as a 'test mic' for one pass,
to my ears, it sounded immediately wrong.
 
a/b'd it against the setting with the factory mic, and sounded the way i would want it to sound.
 
i do not have a 'flat' mic in my collection to experiment with, 
but i'm convinced that specific mics for specific tasks are what's needed.
 
 

Did you bother to switch your large diaphragm mic to Omni?
 
 
 
All the test mics mentioned in the article were very small diaphragm design. They are very similar to Karyn's test mic.
 
 
If you look in your Shure KSM44 user guide you will see that the omni off axis response isn't very Omni above 6400 Hz. In Omni mode, "on axis", the diaphragm has a reduced bass response starting at -3dB at 20 Hz and sloping up near 0dB at 1.2kHz where it presents big resonant +4dB peak centered at 6kHz that then plumments back to -5dB.
 
If you download the cheap as dirt Behringer ECM8000 "Measurment Mic" specifications you will see that the Omni pattern remains fairly Omni at 8000 Hz with a gentle roll off on the side The "on axis" frequency response is relatively flat from 20Hz out to 5Khz where there are a few slight peaks near the capsules resonant frequency that flatten back out after 10kHz.
 
If you are going to try to use another mic for testing... you'll probably want to use a mic that has the attributes of a test mic.

yes i did set it on omni...
point being, i only did it as a test for self amusement.
 
i suspected the results would be what they were.
 
no, i have the proper mic, just because it is the straightest line between the 2 points
 

Glad you got that XLR plug fixed up. :-)

"HAMMER TO FIT"
 
common contractor term.......

Am I wrong in thinking you can get 80% of the way there by sitting in the listening position and playing some test waveforms (i.e. sine sweep from 18kHz - 10 Hz or whatever) and adjusting your favorite EQ plugin?
 
I did this and it made a big difference, but I'd be the first to admit it isn't perfect. But it is better.

You can "fix" the peaks that way, but the "nulls" will still be nulls.
My guess is that ARC does some phase shifting to "fix" the nulls.
It helps a lot in my room.
YMMV
T