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OLLO S5X Headphone Review

Rate this headphone:

  • 1. Poor (headless panther)

    Votes: 31 25.0%
  • 2. Not terrible (postman panther)

    Votes: 59 47.6%
  • 3. Fine (happy panther)

    Votes: 24 19.4%
  • 4. Great (golfing panther)

    Votes: 10 8.1%

  • Total voters


Master Contributor
Forum Donor
Jan 23, 2020
I went back to the review to figure out why I thought they would be non-linear. I think it is THD vs Frequency graph that show levels as dB and THD as % is the culprit. If you convert THD% to dB, looks like they would align linearly indeed.


This is the graph I am talking about. Level is logarithmic, and so is the x-axis, not sure why the y-axis is linear.
Good observations for why you (mistakenly) thought what you did! (yes, good thought process, I hadn't made some of those links in my mind before re that graph.)
Last edited:


Addicted to Fun and Learning
Forum Donor
Nov 11, 2022
We're not gonna go through all that again, we've debated the pros & cons of EQ vs insert, so I don't have anymore to say on that.

So don't.

I also pointed out earlier that you were getting confused by bringing in the whole topic of "EQ'ing a headphone from a measurement you find on the internet"
So you did.

So it's not relevant to be going on about the pros & cons of "EQ'ing a headphone from a measurement you find on the internet" here in this thread

So don't.


Major Contributor
May 12, 2021
Yes, that graph is pretty conclusive, headphone resonances are mostly linear it looks like. Where is it from?
Oratory's measurements, originally shared by @Robbo99999 in this post.
That may be true if the FR and distortion you are referring to is the FR and distortion we perceive. Surely it is NOT true for the 1/12 octave smoothed, rig specific, unreliable measurement data we have though. Let's not pretend they are the same.
Yet reliable enough to get a high correlation of 0.85 between listeners' preference ratings given to real and virtualized headphones using digital EQ based on said rig measurements as found by Harman. And that's only using FR measurements, without replicating distortion, and limiting aggressive virtualization EQ to <8-10kHz. And all this despite nuisance variables such as leakage and tactile cues present in the real tests but not virtual tests, as well as being based on measurements using the old, long since superceded artificial pinnae before Harman started using more anthropomorphic pinnae used in their later preference studies, which better simulate leakage on real human heads. Considering this substantial improvement in accuracy (plus potential other methodological improvements, see below), the virtualization correlation is likely to have increased significantly higher than the 0.85 found with the original pinnae. Dr Sean Olive:
we've improved the accuracy of the virtualization in part by developing a custom pinnae for our GRAS 45 CA that better simulates the leakage effects of headphones measured on real human subjects


Active Member
Mar 7, 2020
The manufacturer has a good idea...
But why not make the size of the ear pads inside 65*45 with a depth of 22 millimeters or angular.
And weighing up to 300 grams.
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