MiniDSP EARs measurement rig

Discussion in 'Headphone Measurements' started by dBel84, Nov 9, 2017.

  1. cskippy

    cskippy Friend

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    That defeats the common reference point...

    I'm still happier with my flat plate measurements.
     
  2. Hrodulf

    Hrodulf MOT: Sonarworks

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    I'm pretty sure that our engineers would figure out how to do it reliably, however we're an evil business entity so it remains to be seen if we would do it.

    Overall EARS looks like something we built around 3 years ago. My colleague still has a large drawer full of his ears replicated in various materials. IIRC, it was a dead end with flat-ish plate couplers giving similar or better results.

    To this day we haven't encountered the perfect tool for artefact-free absolute measurements on all headphones. It's one thing being able to pull off a nice HD800 measurement, while HD25-II is a whole 'nother ballgame. In the end it's more about the hand that swings the blade, rather than the blade itself. Our guys could pull a good measurement from EARS, but only because they have thousands of measurements already behind them.
     
  3. sorrodje

    sorrodje Carla Bruni's other lover - Friend

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  4. Hands

    Hands Overzealous Auto Flusher - Measurbator

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    A reference point would be nice, but we've survived thus far without! And if the mics have too much variance, that could be hard to fully obtain if many are unwilling to go through the trouble to calibrate and compensate for each other. Not that it's too tough, but it takes time. We could end up with a shaky, variable reference point or just never see enough drive among enough people to get it to that point. But it could work, and I hope so. I for one won't use it as-is because CSDs are unusable with that plain canal. I like being difficult.

    But, really, all I meant to say is if you get tired dealing with it entirely, salvage some parts for better use. The mics and USB board alone could be very handy if it all fizzles out.
     
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  5. Marvey

    Marvey Sundry Accessory

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    It's pretty much a pain in the ass, but having lots of legacy data and new data with the EARS does help. I spent a little bit of time every day analyzing the data since I got the EARS to arrive at the preliminary compensation I posted above.

    I wouldn't mind calibrating individual members EARS, for SBAF members that is, for a nominal fee or a good bottle of whiskey, bourbon, or scotch.

    Tyll sent me an ear many years back, but I still decided to opt for the flat plate. The flat plate coupler results are "good enough" for frequency response. It can be argued that couplers with ears might be more accurate with a larger variety of headphones where the ear may interact differently with the internal cavity inside the cups. But really, at the end of the day, most headphones are more simlar to each other than not. I've always like to point out how the flat coupler measurements here look suprisingly similar to Jude's GRAS45AC results.

    Where the flat couplers win are with distortion measurements (lower noise for not having to record at lower gain to account for ear gain), immunity to measurement variance from placement, and maybe CSDs. The GRAS45AC might be a good candidate for CSDs, but this is hard to say without more analysis (not a priority for me at this time). Likewise, it seems that moving the microphone flush to the ear eliminates ringing / standing waves from the canal - at the expense of more ragged peaks and dips in the highs.

    All that being said, the MiniDSP EARS (or the GRAS45AC) results are a good check for the flat plate coupler frequency response results. From what I am seeing so far, I do like the compensated EARS results for frequency response more than the flat plate coupler results. The EARS CodeX3 frequency response measurement I felt was more indicative of what I heard compared to the V2 flat plate.

    We can even do fun stuff like offer a compensation that translates the EAR results into compensated Jude GRAS45AC frequency response measurements. It probably wouldn't be perfect, but it might be close enough to offer meaningful measurements to compare against Jude's results. The GRAS45AC does have its own eccentricities.

    We'll definitely be getting more data in, and I would look toward you guys to help formulate an SBAF compensation curve for the MiniDSP EARs.
     
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  6. Taverius

    Taverius Acquaintance

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    Bottle of good booze (or two) for your time and expertise, sound like a bargain.

    Learning to do measurements isn't the issue at all, calibrating with no clue or data at the same time - I ain't a superhero with sound-based powers.
     
  7. AllanMarcus

    AllanMarcus Too much posting, not enough reading

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    Just not something one sees too often! Hope it didn’t hurt when Tyll removed it. :)
     
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  8. Tyll Hertsens

    Tyll Hertsens Grandpappy of the hobby - Special Friend

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    I've got another one somewhere if someone wants it.
     
  9. murray

    murray Friend

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    Van Gogh was an early pioneer of the art (puns intended).
     
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