CAUT

Documented Mics and Placements Affecting the Frequency Measurements

  • 1.  Documented Mics and Placements Affecting the Frequency Measurements

    Posted 01-12-2024 21:11
    This is documenting the fact that, indeed, with two parallel recordings of B1, post processing them in Matlab to extremely high resolution frequency analysis, harmonic by harmonic, the results are rather startling. The sensor and mic are not picking up the exact same frequency. Not to question the interpolation in my Matlab analysis, the frequency interpolation is good down to a few parts per million, micro cents that is. You can clearly see that there will be an ETD recorded difference (depending on how good the ETD's frequency measurement algorithm is), of more than 1 cent on some harmonics. The standard deviation of the first 6 harmonics is 0.65 cents in this example.
    Prof. Norsworthy 
    Mic vs Sensor Frequency Differences
    B1 Sensor vs Mic Spectra


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    Steven Norsworthy
    Cardiff By The Sea CA
    (619) 964-0101
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