Dagogo interview of Earl Geddes

[MediumRare]

Here's an article Keith Howard wrote, it's over my head but probably not over yours:

http://www.gedlee.com/Papers/THD_.pdf

Excellent, thanks. So in layman’s terms, it weights the type of harmonic distortion based on the number of the harmonic and its relationship to amplitude, all to better correlate to our understanding of psychoacoustics. (Did I get that right?)

So, can one of you math whizzes (@MZKM ?) take an FFT provided by @amirm and generate the metric for some speakers already tested?

 

[Duke]

Excellent, thanks. So in layman’s terms, it weights the type of harmonic distortion based on the number of the harmonic and its relationship to amplitude, all to better correlate to our understanding of psychoacoustics. (Did I get that right?)

So, can one of you math whizzes (@MZKM ?) take an FFT provided by @amirm and generate the metric for some speakers already tested?

My understanding is that the GedLee Metric is concerned with nonlinear distortion, which is generally not an issue for loudspeakers unless they are pushed beyond their linear limits. In other words, it's not applicable to speakers.

 

[MediumRare]

My understanding is that the GedLee Metric is concerned with nonlinear distortion, which is generally not an issue for loudspeakers unless they are pushed beyond their linear limits. In other words, it's not applicable to speakers.

Let's find out. Amir has mentioned dissatisfaction with some scores not matching his subjective impressions.

Or let's examine amplifiers - tubes v SS for example. In other words, let's see if we can measure things the subjectivists have been saying for years but have not been captured in THD/IMD.

 

[Lbstyling]

Excellent, thanks. So in layman’s terms, it weights the type of harmonic distortion based on the number of the harmonic and its relationship to amplitude, all to better correlate to our understanding of psychoacoustics. (Did I get that right?)

So, can one of you math whizzes (@MZKM ?) take an FFT provided by @amirm and generate the metric for some speakers already tested?

Oh your just outright dangerous arnt you!

In all fairness, we know that:

-Harman group products are science and fact focused.
-Revel and JBL (for instance) are designing for very low distortion.
-It's not easy or cheap to do.
- in many designs (More JBL) they will drastically cost save on things that are not strongly audible (such as cabinet thickness)
-yet they spend considerable money on copper Faraday rings etc on their drivers.

They clearly take great efforts to lower distortion.

The higher distortion IL10 measured extremely well, yet amir (and myself in this case) rate the speaker as lacking detail.

I have subjective experiences that I would happily add, but that's enough for me to come to the conclusion that although as toole says pattern control accounts for 70% of preference (or so) that's Vs speakers with poor pattern control.

Against many modern designs with excellent control, distortion likely correlates with preference.

The more I read geddes papers, the more I think he is under appreciated (but perhaps a bit blunt)

'Geddes is a blunt Toole'
Lol.

 

[Duke]

Amir has mentioned dissatisfaction with some scores not matching his subjective impressions.

Very interesting! Do you happen to know which speakers those were, off the top of your head? I'd like to read what he had to say. If not that's okay, I'll dig through and find out.

Or let's examine amplifiers - tubes v SS for example. In other words, let's see if we can measure things the subjectivists have been saying for years but have not been captured in THD/IMD.

Well I'll pass along this anecdote: After he had analyzed the data for his distortion perception papers, Earl said to me: "Now I understand why you and your friends like tube amps."

Just to be clear, Earl is NOT a tube amp guy. Actually he used (and may still use) a Pioneer receiver which scored exceptionally well by the GedLee Metric. The engineer in Earl doesn't believe in paying a premium for what he considers to be a small improvement.

 

[MediumRare]

Very interesting! Do you happen to know which speakers those were, off the top of your head? I'd like to read what he had to say. If not that's okay, I'll dig through and find out.

@amirm will answer better, but here's one https://www.audiosciencereview.com/...aph-audio-za5-2-diy-kit-speaker-review.12086/ and another https://www.audiosciencereview.com/forum/index.php?threads/kef-q350-speaker-review.13484/ and here's a bad score that sounded good: https://www.audiosciencereview.com/forum/index.php?threads/jbl-xpl90-speaker-review.13449/

 

[Duke]

@amirm will answer better, but here's one https://www.audiosciencereview.com/...aph-audio-za5-2-diy-kit-speaker-review.12086/ and another https://www.audiosciencereview.com/forum/index.php?threads/kef-q350-speaker-review.13484/ and here's a bad score that sounded good: https://www.audiosciencereview.com/forum/index.php?threads/jbl-xpl90-speaker-review.13449/

Thank you VERY MUCH!!

 

[Lbstyling]

Duke:

The infinity IL10 was the most notable.

 

[Duke]

Duke:

The infinity IL10 was the most notable.

Very interesting that there's a lack of clarity/grunginess which doesn't show up in the measurements. I presume there is a measurement which would reveal it, but measuring everything is not practical and may not be possible.