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Why don't all speaker manufacturers design for flat on-axis and smooth off-axis?

neph

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In order to assess the impact of controlled directivity, it would be interesting to have a repeat of the Harman blind test but including speakers design (or should i say marketed) with different chief design approaches and at least share very good on-axis response, for example:

Controlled directivity as chief design trait
- Revel Salon 2
- KEF reference 5 (uni drivers)

Non controlled directivity as chief design trait
- ATC scm 100 (low distortion)
- Dunlavy (phase accuracy, perfect step response).
- B&W (?)
 

617

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Technically correct speakers make good references for evaluating recordings but they are not necessarily the most musically enjoyable speakers to everyone. Yes, average listeners in laboratory settings prefer a flat and smooth frequency response, but many audiophiles see the sound produced by their system as something which they have built to explore music according to their taste and understanding. Musical taste has a lot to do with it - how can one 'correct' speaker be ideal for everything if recordings vary so much? In this sense, a technically perfect speaker becomes a jack of all trades and a master of few. If you listen to ancient jazz and blues recordings, or solely to classical, or modern electronic music, the ideal speaker will vary. A speaker with low distortion, flat FR and smooth directivity transitions will probably not sound terrible on many recordings, but we can't really blame people for liking the sound of dipoles, or harbeths, or horns, altec coaxials, line arrays, and any other number of fundamentally compromised but beloved speakers.

It is not simply an issue of marketing or the incompetence of the designers. Audiophiles simply have different goals than neutrality, and speaker designers provide them with options.
 

Krunok

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Well it is part of the inherent flaw of stereo reproduction. So far I have not seen any such corrections when playing stereo recordings via AV recievers. There is one commercial 3.x system playing stereo recordings using three speakers that I know of that probably do some of these corrections.

Ok, but how is that related to flat on-axis and smooth off-axis response?
 

Krunok

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It is not simply an issue of marketing or the incompetence of the designers. Audiophiles simply have different goals than neutrality, and speaker designers provide them with options.

Sure.. Assuming you have an option to listen to the speakers you are interested in at least for 7 days at your home with an option to return them if yoyu are not satisified. What do you think what percentage of the speakers are sold that way?
 

Thomas_A

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Ok, but how is that related to flat on-axis and smooth off-axis response?

As mentioned the measured ”flat” on axis may not be the one that is preferred for stereo but one that is adjusted within +/- 1 dB at given frequency regions. Although the data is there in Tooles work, I don’t think the experiment has been done but he (Toole) both admits and hears the stereo system flaws.
 

Thomas_A

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And when it comes to directivity I think that it should be smooth and mimic the direct response. But the amount of dispersion is a question more complex in relation to room size and the reflective surfaces close to the listening position.
 

MRC01

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Eg the timbral difference of a phantom centre of two stereo speakers compared to a true centre mono source.
And how would you correct that?
With a slight increase in the 1-2 kHz region and a dip in the 3-4 and 7 kHz region.
My Magnepan 3.6/R show this characteristic when measured from the listener position. I don't know whether they did that intentionally; I thought it was an anomaly and EQed it out. Listening to it both ways, I prefer the EQed version, sounds more natural & realistic with most recordings of acoustic music.
However, this could be because it's not uncommon for classical music recordings to be mastered with a touch of artificial emphasis in the upper midrange (1-2 kHz).
 
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napilopez

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Technically correct speakers make good references for evaluating recordings but they are not necessarily the most musically enjoyable speakers to everyone. Yes, average listeners in laboratory settings prefer a flat and smooth frequency response, but many audiophiles see the sound produced by their system as something which they have built to explore music according to their taste and understanding. Musical taste has a lot to do with it - how can one 'correct' speaker be ideal for everything if recordings vary so much? In this sense, a technically perfect speaker becomes a jack of all trades and a master of few. If you listen to ancient jazz and blues recordings, or solely to classical, or modern electronic music, the ideal speaker will vary. A speaker with low distortion, flat FR and smooth directivity transitions will probably not sound terrible on many recordings, but we can't really blame people for liking the sound of dipoles, or harbeths, or horns, altec coaxials, line arrays, and any other number of fundamentally compromised but beloved speakers.

It is not simply an issue of marketing or the incompetence of the designers. Audiophiles simply have different goals than neutrality, and speaker designers provide them with options.

You bring up some good points. Though to your point about different speakers being better for different genres, I can see this being true to a certain extent, but I feel there's enough variation within the confines of "flattish" response and "smooth" dispersion to accommodate for genre differences and individual preferences. The NRC and Harman studies seem to suggest these qualities are largely beneficial irrespective of genre (along with bass extension, not to be ignored).

Certain genres seem to 'dampen' the difference between speakers, but I've not seen anything to suggest a specific type of music will cause people to prefer a speaker with a particular idiosyncratic sound over the flattish one. If anyone has research suggesting otherwise, I'd love to read it! I've seen individual manufacturers claim their speakers perform better in blind tests... but not seen the data to back it up.

Of course, there will be outlier individuals, but that doesn't seem to be a good demographic for a speaker company to base its income on...

Moreover, I rarely see speaker companies themselves claim their speakers are better for specific genres or designed with a particular type of music in mind. Maybe there's a speaker that's perfect for jazz-infused k-pop with a smokey vocalist, but marketing materials are more likely to say something like "hear music as the artist truly intended!", (something studio monitors and neutral speakers seem closer to replicating than esoteric designs.)

Again, don't get me wrong. I'm fine with listener preferences. Speakers shouldn't sound exactly the same. Buy what you like! Heck, make your choice purely on aesthetics if that's paramount to you - aesthetics factor strongly into my own choices. But to me, the value of the Toole/Harman research is... well, value.

Much in the same way Amir has shown you don't have to spend a fortune to get an audibly transparent DAC, the Harman research shows the point of diminishing returns among speakers can begin a lot cheaper than people assume.
You'll often hear audiophiles say they make their choices purely on sound quality, but blind tests appear to reveal this is often not the case.

Measurements that correlate with listening preferences keep us honest.They ask people to reconsider why they're spending multiple grand on a pair. And they suggest that if a speaker company is charging out the wazoo primarily on promises of sound quality (rather than design, build quality, or features), it better have some state of the art performance to match.
 

amirm

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Controlled directivity as chief design trait
- Revel Salon 2
- KEF reference 5 (uni drivers)

Non controlled directivity as chief design trait
- ATC scm 100 (low distortion)
- Dunlavy (phase accuracy, perfect step response).
- B&W (?)
B&Ws are a fixture in Harman studies. It is often disguised as speaker "B." Indeed it was among the pool of speakers when I participated in the blind tests:

harman speaker test blind.jpg


It is the one to the left.

I scored the JBL the highest (on the right), then B&W and finally Martin Logan in the center.
 

617

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Amir, I find it pretty amazing that they're doing blind tests of speakers this different. Could you tell that one speaker was a dipole?
 

amirm

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Amir, I find it pretty amazing that they're doing blind tests of speakers this different. Could you tell that one speaker was a dipole?
I had no idea it was dipole. But I gave it poor scores. At first I thought it was a control speaker that was designed to sound bad. I was shocked to find it was the Martin Logan. Vocals sounded especially strange, hollow.
 

Thomas_A

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My Magnepan 3.6/R show this characteristic when measured from the listener position. I don't know whether they did that intentionally; I thought it was an anomaly and EQed it out. Listening to it both ways, I prefer the EQed version, sounds more natural & realistic with most recordings of acoustic music.
However, this could be because it's not uncommon for classical music recordings to be mastered with a touch of artificial emphasis in the upper midrange (1-2 kHz).

Hmm well the Magnepans differ quite much more than +/- 1 dB on axis according to Stereophile so I don’t think it is strange that you prefer EQ.
 

Kal Rubinson

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Eg the timbral difference of a phantom centre of two stereo speakers compared to a true centre mono source.
Well, the use of a center channel inherently corrects for that. :facepalm: Of course, there still are always "phantom images" between adjacent speakers in stereo and multichannel.
 

digitalfrost

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I like my MartinLogan reQuests, the design of which which rates poorly on the Harman/Toole/Olive preference scales, but after 21 years with them, and despite having a set of "approved" speakers right next to them for easy comparison and daily casual use, don't feel a need to take them to the dump.
A friend of mine auditioned Martin Logan Motion 20 vs. KEF R500 a couple of years ago. We had both in his living room side by side. We ended up deciding on the R500s, mostly because they did a much better job of sounding real with movies and real sounds like walking down stairs. But what the Motion 20 did with music was magic. Their measurements are horrible:



(Motion 40 shown here)

I'd still like to own them. That said. I think designers that do not go for neutral should be honest about it. Anyone who isn't only contributes to
[URL='http://seanolive.blogspot.com/2009/10/audios-circle-of-confusion.html']Audio's Circle of Confusion
:

Circle+of+Confusion.png
[/url].
 

amirm

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But what the Motion 20 did with music was magic.
It is. Problem is, the magic is inserted into everything you play. A lot of music should NOT sound diffused, open or whatever you call it. But they all do with some speakers like these.
 

daftcombo

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A friend of mine auditioned Martin Logan Motion 20 vs. KEF R500 a couple of years ago. We had both in his living room side by side. We ended up deciding on the R500s, mostly because they did a much better job of sounding real with movies and real sounds like walking down stairs. But what the Motion 20 did with music was magic. Their measurements are horrible:



(Motion 40 shown here)

I'd still like to own them. That said. I think designers that do not go for neutral should be honest about it. Anyone who isn't only contributes to
Audio's Circle of Confusion:
.

+10 dB between 600 kHz and 1.4kHz??!
 

Ron Texas

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Some interesting nuggets here. I get the impression Dr, Toole's work was about preference. That word may mean different things to different people, but the research produced statistically significant results. If you want to be in the business of making speakers then you want your speakers to be preferred. As for accuracy or fidelity to the original performance, there are endless discussions of what that means, and it will never end.
 

amirm

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That word may mean different things to different people, but the research produced statistically significant results.
I took the test on two different occasions and my results matched the larger population.
 

617

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I think panel speakers exaggerate treble to make up for the very narrow directivity in this region, just to get some HF into the room.

Panel speakers really damage the reputation of dipoles. Dipole dynamic speakers can do things no other speakers can. RIP Siegfried.
 

RayDunzl

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It is. Problem is, the magic is inserted into everything you play. A lot of music should NOT sound diffused, open or whatever you call it. But they all do with some speakers like these.

Just for the record, in case there is some confusion, the Motion 20 isn't a panel...

1563313722461.png
 
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