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Old 29th November 2017
  #212
Gear Guru
Cal

Quite a broad topic in itself. Worth remembering that this all started using the Mic in a Radio Shack SPL meter. An utter POS. Cheap half decent mics became available, but the response of some, Behringer, is extremely varied, while others, the UMIK-1 seems to have only slight variation from one mic to the next. Then there is the quality of the Cal Files. There is some thread here where we got into it a bit and found quite a difference between the UMIK and some other, both using their Cal files. Can't remember further detail, but I will say that a UMIK here, using it's Cal file which has quite small corrections, creates measurements which are extremely close, identical really, to a Bruel and Kjaer.


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1. Is the mic calibration just more or less useless fine tuning in the environmet, where there are even bigger uncontrollable sources of errors?
The Mic Cal is done in some sort of Lab or otherwise controlled environment.

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2. The MM1 comes with a individual mic response graph - isnĀ“t it enough, that I just take in to consideration that curve, i.e. the deviation of that individual mic to the absolutely flat response, when drawing the conclusions after the room measurement?. E.g. if there is a notch in mic curve in 1 kHz, I know that a similar notch in the REW results depend (partly) for the mic error?
Is there really any need for the mic calibration, in this type of measurement?
If the mic is pretty flat, as one would expect from a German manufacturer, there will be little difference between using a Cal File and not.

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3. However, is the MM1 calibration is recommended by you, please advice me how to do, excactly - as you can read in the home theatre site comments, there might be some confustion how to do it correctly.
I don't know that Mic, or the veracity of it's Cal File. With no data below 60Hz, and a pretty flat published or individual response, I wouldn't bother with the Cal.

DD