MiniDSP EARS: Deriving SBAF compensations from MiniDSP files?

Discussion in 'Measurement Techniques Discussion' started by purr1n, Nov 7, 2018.

  1. purr1n

    purr1n Finding his inner redneck

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    I don't remember who asked me for this, but I am finally posting this information. I am hoping that folks with EARs interested in using the SBAF headphone compensation will be able to derive it from the HEQ files provided by MiniDSP.

    https://docs.google.com/spreadsheets/d/1uUqkpD3EJMzpl8FeJbNOkjApvMKAIL3IP8Y1At_ldng/edit?usp=sharing

    See related threads:
    https://www.superbestaudiofriends.org/index.php?threads/calibrating-minidsp-ears-part-2.6880/
    https://www.superbestaudiofriends.org/index.php?threads/minidsp-ears-measurement-rig.5377/

    Here are the deltas of the custom SBAF FR compensations for my EARS to the MiniDSP provided compensations. They are by no means perfect; but I feel comfortable enough running with them now. A few things to keep in mind:
    1. I have no idea if adding back the SPL difference will actually work with your individual EARS. The L and R differentials derived from files provided by MiniDSP were quite a bit different from my L and R and differentials. I am very concerned about this.
    2. One issue I had was to get every headphone to look right, to reflect what my ears are telling me, but this seems impossible. Tweak one thing that makes one headphone's measurement look right, and it screws up another headphone's measurement. These compensations are a compromise and balancing act. At the end of the day, it's good enough and it works given the limitations of the EARS which is a budget product.
    3. Frequency response plots derived from the SBAF EARS compensations will be very different from other plots. The target for perceptual neutral was intended to be a flat horizontal line straight across the graph. It's very important to keep this in mind.
    4. The plots here were derived from multiple measurements of over a half dozen headphones. Because of inconsistencies in the positioning process, I applied weighted averaging of results. Some headphones are more immune to positioning variances. Other less so. Data which I felt was obviously bad was thrown out or re-acquired.
    [​IMG]
     
    Last edited: Nov 7, 2018
  2. purr1n

    purr1n Finding his inner redneck

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    Here was my first test case AFTER the compensations were developed. This headphone I did not have on hand to develop the compensation, so it a good test case. My concern still lie with L/R channel matching.

    ZMF Verite - thick pads.
    [​IMG]
     
    zach915m, maverickronin and Lyer25 like this.
  3. Vtory

    Vtory Illogical Spock

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    Great! Did you not correct phase info? Or, just use what minidsp corrected for phases?
     
  4. purr1n

    purr1n Finding his inner redneck

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    Just use miniDSP provided phase.
     
  5. Vtory

    Vtory Illogical Spock

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    Compensation comparison (sbaf vs mine v3).jpg
    (No smoothing)

    Tried to apply sbaf compensation curves to my elex measurements. Because my EARS were surprisingly well-matched between left and right channels (note: I very recently purchased ears), applied marv's delta after averaging left and right.

    Honestly a bit surprised that difference is much less than expected.
     

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