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Old April 27th 05, 08:28 AM
Richard Clark
 
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On Tue, 26 Apr 2005 20:28:01 -0500, Tom Ring
wrote:

Any references on microphone calibration? Maybe a short tutorial? That
is something I have a need to do.


Hi Tom,

As a second thought, you may not be in the market for the reciprocity
technique (it does require that you have a true reference microphone).

In that case, you would fall back to a Piston Phone and do a single
point calibration. The method is as old as the hills, the math is
extremely simple volumetrics, but the implementation (construction of
the calibration unit) is not something for the faint of heart. You
will need a precision lathe. Again, google using Brüel & Kjær as a
jump-off point.

Once you do the single point calibration, then you can proceed to a
swept frequency analysis. Unfortunately this returns us to the
necessity of a reference microphone. However, as relative frequency
response is more available (from expensive retail models), you might
have a chance.

73's
Richard Clark, KB7QHC