Yes, I was purely talking about other papers.
btw, maybe nice to share a link to your papers so people here can find and read it as well.
THD is a useful measure for indicating how loud a well designed speaker can play before distortion starts to intrude. 1% and 3% THD curves on an SPL vs frequency plot ought to be a part of the specs for all speakers with claims to high fidelity because it shows how loud they can play cleanly.
Obviously some forms of distortion (e.g. a sequence of clicks) can be audible at minute levels of THD but they won't be present in well designed speakers (and it isn't sensible to quantify this type of distortion with THD).
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They are all on my website and in the AES library.btw, maybe nice to share a link to your papers so people here can find and read it as well.
The relevance of this is what when it comes to setting the level where raising the SPL of a well designed speaker is starting to create noticeable levels of nonlinear distortion? I presume you are not suggesting that we change from using 1% and 3% levels and use 20% instead? Or that determining a clean operating range for a speaker is of no interest?
The audibility of the nonlinear distortion typically generated by well designed speakers is not difficult to establish by simply turning the volume control up until it is noticeable. Personally I have little interest in the subjective sound of nonlinear distortion only in ensuring it is low enough in level to be of no consequence. THD is a simple and reasonable way to do that for well designed speakers given the complexities of using multi-tones. Not perfect but good enough if the objective is to identify a clean operating region.
I agree....it is such an easy, simple, and telling test. Most home audio type speakers get strident all too soon, as volume is turned up.... ime.
On my stronger speaker builds, that maintain relatively low distortion measurements at high SPL.....
well, they just sound better and better as I turn the volume up....
Proof about THD audibility one way or the other? No.
Common sense proof that designing for clean measuring SPL matters? I think so.
Indeed, so the goal is greater system efficiency, i.e. current system is > ~99 dB eff./stereo/~14 Hz in room with dual 30 W rated woofers @ low enough distortion to not be noticeable to all but the most keen of hearing (youths/females) IME at rated power = 10log(60) = ~18 + 99 = 117 dB/m/channel peaks/97 dB avg. dialog, so significantly > THX cinema reference's 85/105 dB, ditto the LFE's 95/115 dB due to corner loading (ancient cheap RS meter isn't up to the task, so not sure beyond guessing > 100/120 dB), which is much too loud for most folks in a typical size HIFI/HT app and with the changing demographics of my neighborhood over the decades now much too high for me, though (competition level?) 'boombox' vehicles till bedtime and after Sunday Church services are fine though........ 
I meant my neighbor's boomboxes and their much louder/obnoxious 'brothers/sister's' that traverse my through street connecting two major highways at all hours of the day/night; i.e. beyond helping them go (more) deaf when asked, I've never been interested in any more (sub) bass than required for a given soundtrack/app, so having driven most of my life in either a roadster/convertible or on a motorcycle I've mostly had the bass rolled off.
It is interesting to consider what levels of THD we would accept from an amplifier compared to a speaker.
As an occasional fan of high SPL , I set about having a sound system with extremely high headroom.
With 700W per Ch. of high current amp. + bass by 15" & 12" per Ch. & 6x 5.5" in my line array >
nothing ever gets overdriven into higher levels of distortion. Also, having 6 drivers from 600Hz to 4Kz
keeps (the very debated) doppler distortion to a very low minimum.
I like having my system this way
As an occasional fan of high SPL , I set about having a sound system with extremely high headroom.
With 700W per Ch. of high current amp. + bass by 15" & 12" per Ch. & 6x 5.5" in my line array >
nothing ever gets overdriven into higher levels of distortion. Also, having 6 drivers from 600Hz to 4Kz
keeps (the very debated) doppler distortion to a very low minimum.
I like having my system this way
Just actually giving the website links is also a lot less cryptic;
http://www.gedlee.com/Papers/papers.aspx
Can't link the AES search, because their bloody URL doesn't work that way..............
@gedlee I only can't find the >50 sample size, only 34 participants (or 37, both numbers are being mentioned, which is kinda confusing)
http://www.gedlee.com/Papers/papers.aspx
Can't link the AES search, because their bloody URL doesn't work that way..............
@gedlee I only can't find the >50 sample size, only 34 participants (or 37, both numbers are being mentioned, which is kinda confusing)
What are you trying to say or ask with this?
Reviewed or not doesn't change the findings of a paper.
It might sometimes change the overal point of view of a bigger group of scientists.
Although that heavily depends on how those peers feel about certain subjects as well.
Or how a certain idea should be implemented (or not).
For discussing it in detail, I would go back to an old topic;
https://www.diyaudio.com/community/threads/the-gedlee-metric-demystified.287291/
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Again, I don't remember specific details of each paper and we did numerous multiple subject studies so the specific number of subjects on any particular study has been forgotten. The papers always list this number, so just look it up.
Lidia did the analysis of variance for each study and we did not publish anything unless the results were statistically significant. In fact one of the most interesting studies that we did was not published for this reason, even though I found the results to be quite interesting.
These numbers are directly from the papers, including conflicting numbers, that's why I was asking.
