Audio Control CM10

I recently borrowed an Audio Control CM10 measurement mic to compare it with other measurement mics I own.

Audio Control CM-10

Audio Control CM10
For a sound source, I used a QSC KW122 speaker. The DUT (devices under test) are the mics. If I used the one mic and measured a batch of speakers, the speakers would be the DUT.
The comparison was between:
Audio Controls CM10
Earthworks M30BX (self powered)
Audix TM1 (current measurement mic model)
Audix TR40a (discontinued measurement mic model)

In the following image, note that the mic traces match closely in frequency response until about 4kHz and then only the CM10 begins to deviate from the other traces. This indicates that the frequency response of the CM10 above 8kHz is less accurate than the other mics. Even so, the deviation is minor. Maybe 4db off from the rest at certain frequencies.
Audio Control CM10 comparison

This next image was made using the ZOOM function in Smaart 7. I have zoomed in to the range between 5kHz and 20kHz so the CM10 deviation is more noticeable.
Audio Control CM10 comparison 5k to 20k

To simplify things, the next image is a comparison between just the CM10 and Audix TM1.
CM10 : TM1 comparison

This is a zoom between 5k and 20k of the same two microphones.
CM10 : TM1 comparison 5k to 20k

I would need to measure a sample of brand new Audio Control CM10 units to know for sure if this older CM10 mic meets the factory spec for the mic. One could certainly make relatively good decisions about system optimization using the CM10 measurement mic.