Is Jay talking about Amir?

[restorer-john]

So what is exactly the fight here? Is it that @kimmosto doesn't think CEA 2034-A-2015 is predictive in terms of loudspeaker preference?

Nobody knows. I think it's a disagreement for the sake of it.

We are all on the same side, last time I checked.

 

[redshift]

Nobody knows. I think it's a disagreement for the sake of it.

We are all on the same side, last time I checked.

Yes, what is better, a 0.30mm standard fishing line, or perhaps a 0.15mm woven line. Well, I guess it depends on what kind of ugly fish you want to catch.

 

[Blaspheme]

Give me some examples of the coherence you are talking about. And what makes them less amateurish. I am hoping you are not going by word count and product descriptions....

Are you saying you're unaware that your writing is pretty rough?

 

[Blaspheme]

Normalization (to the frequency response) is not allowed in this case because the measured distortion values behave in a non-linear way and thus normalized curves would not be comparable.

But I have to agree with you, the presentation of IMD of S&R (sound and recording magazin) is not helpful in terms of comparability with other speakers.
In the PA market it might be helpful to know that for a loudspeaker A the average IMD of 10% is reached at 104dB SPL and for loudspeaker B at 107dB.

It would be much better if there were IMD measurements for fixed sound pressure levels (e.g. 85, 95, 105 dB) and then the limits for 1%, 3% and 10% IMD, based on the individual frequency response of the loudspeaker, were plotted there.

This could then look something like this:
View attachment 141754 View attachment 141755 View attachment 141757
Source: https://www.lowbeats.de - additional curves were drawn by me
In this way, the measured multitone distortions MD (HD + IMD) are directly comparable. One could also immediately see where a speaker has particularly big problems.
For me this kind of evaluation is easy to understand, but I don't know anyone who uses this (apart from me ).

It would be even easier to understand if the MD were given directly as a frequency-dependent percentage value curve - I agree with Amir on this.

Whether this kind of evaluation of IMD brings an added value or whether the measured harmonic distortions basically already anticipate the result of the IMD measurement in 99% of the cases***, would have to be examined more closely on the basis of selected loudspeaker measurements.

*** Update:
The statement refers to "comparable" speakers. If one 2-way loudspeaker has an f3 of 80Hz and another has an f3 of 40, there are of course significant differences in IMD (for the same driver size) that are not captured by an HD measurement.
In this case, the IMD measurement provides added value.

If both speakers were equalized to the same frequency response, then most likely the speaker with the lower HD will also have the lower IMD (but that is just my experience).



I couldn't agree more. The THD evaluation of S&R does not allow a comparison of the results of the individual tested speakers, because it is not clear by which order of harmonic distortion the THD is significantly influenced.

The measurements of the harmonic distortions HD, splitted into HD2 to HD5, as shown by @amirm or @hardisj, are much more informative, especially because the masking decreases significantly with the increase of the order of the HD.



The Geddes and Lee studies were certainly in the right direction, but unfortunately the correlation was not very high.

Source: Perception & Thresholds of Nonlinear Distortion using Complex Signals

There are other approaches that are more promising, but for many completely unknown - see linked study.
The study is already a few years old, I am not up to date on the latest developments.

I also like the harmonic series presented under FR on the same dB scale (the number of harmonics that can be clearly interpreted depends on the style and resolution of the graph, however, hence my preference for zoomable vector pdf). Neither of those tell us about speaker behaviour as volume increases. Amir's linear 0-5% scaled versions aren't great. I think the S&R IMD examples are more informative than the compression graphs used sometimes (but not here).

Your graphs are good. And yes I agree we'd need levels and metrics appropriate to hifi speakers in normal size rooms. If that's sorted, then they can be used to compare speakers.

 

[Koeitje]

Nobody knows. I think it's a disagreement for the sake of it.

We are all on the same side, last time I checked.

Ah ok, I skimmed through some posts and it all was very confusing.

 

[redshift]

I also like the harmonic series presented under FR on the same dB scale (the number of harmonics that can be clearly interpreted depends on the style and resolution of the graph, however, hence my preference for zoomable vector pdf). Neither of those tell us about speaker behaviour as volume increases. Amir's linear 0-5% scaled versions aren't great. I think the S&R IMD examples are more informative than the compression graphs used sometimes (but not here).

Your graphs are good. And yes I agree we'd need levels and metrics appropriate to hifi speakers in normal size rooms. If that's sorted, then they can be used to compare speakers.

Is it possible to make amplitude/energy responses as well as frequency responses with these software packages?

Then it would be possible to observe how other properties, dist. etc. changes with the volume similar to those 2D plots for frequency response?

 

[BluesDaddy]

Are you saying you're unaware that your writing is pretty rough?

Nice passive aggressiveness there.

 

[Blaspheme]

Is it possible to make amplitude/energy responses as well as frequency responses with these software packages?

Then it would be possible to observe how other properties, dist. etc. changes with the volume similar to those 2D plots for frequency response?

I wonder about that, assuming Klippel (say) gives you harmonic distortion, then sweeps at different amplitude/levels would collect dynamic data. The fun would be visualising it coherently. It's difficult to display contours within/beneath other contours. If you do slices, then how many, etc.

 

[Blaspheme]

Nice passive aggressiveness there.

Not really, I want to know if I'd be wasting my time.

 

[BluesDaddy]

Not really, I want to know if I'd be wasting my time.

Right...

 

[DonH56]

Not really, I want to know if I'd be wasting my time.

Yes.

It's not a journal article, it's his website, so informal writing style is OK and it is easy enough to look past the typos and "interesting" grammar to the information in the reviews.

Not that my writing will win any awards.

Missing the big picture?
"The world is going to blow up!"
"You should have said 'explode'..."

 

[Blaspheme]

Yes.

It's not a journal article, it's his website, so informal writing style is OK and it is easy enough to look past the typos and "interesting" grammar to the information in the reviews.

Not that my writing will win any awards.

Missing the big picture?
"The world is going to blow up!"
"You should have said 'explode'..."

Not only is it a website/blog—which neither precludes good writing, nor requires it—while Amir asked for examples, I judged the request rhetorical. Also, we've all seen how "those" conversations go.

 

[amirm]

Not only is it a website/blog—which neither precludes good writing, nor requires it—while Amir asked for examples, I judged the request rhetorical. Also, we've all seen how "those" conversations go.

There was nothing rhetorical about my question. I wanted to know what you thought was amateurish. Now you are playing a game of Calvinball by saying the writing is "rough?" You don't understand the difference between the two words?

But yes, you have dragged this conversation into mud. A world-class luminary, Dr. Sean Olive, came into the thread and instead of engaging him and learning from his immense knowledge and expertise, you decided to take pot shots dressed as "advice."

Anyway, since nothing constructive is coming from the few of you complaining, I am going to close the thread.