Mic Sensitivity

[Chuck Gerlach]

I'm trying to use my Earthworks M30 mic to compare it to the other mics I am using. The issue appears to be the M30 is far more sensitivity OR what I am trying to use as a sensitivity factor as the first line of the cal file is inappropriate.

The sensitivity of the M30 mic is listed as 8mV/Pa (-42dBV/Pa). What exactly should the first line of the cal file look like to make this work? I tried the following but to know avail. As an FYI, the REW SPL reading of one of my other mics is around 38dB, while that of the M30 is around 88 to 90dB. And, needless to say, when I try to use it I get an signal to noise ratio error message. The sensitivity line entry was not part of what I received from Earthworks re-calibrating my mic a few months ago. (Forget the -41.2 vs what should have been -42)

Thanks.

 

[John Mulcahy]

The sensitivity figure to enter is the REW dBFS input reading when the mic is driven by a 94 dB calibrator.

 

[Chuck Gerlach]

Thanks:

I can't locate my (1/4") Earthworks adapter to fit into my 1/2" calibration device, so I have one on order, though I'm not 100% sure that is all of the problem. Even when I calculated and used a sensitivity figure that gave me a close SPL reading using the SPL meter function, there is something amiss as the little graph in the lower left corner has far more deviation than with my other mics and the FR reading I got was not even close.

Once I get my adapter, I will give it another go and re-connect if necessary.