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Beyond Linearity: Why Speaker Dispersion Matters Far More Than People Expect

anphex

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Beyond Linearity: My Journey into the World of Speaker Dispersion

Four years ago, I stumbled upon ASR almost by accident, while troubleshooting an Emotiva amp issue. At that point, I had no idea I'd soon be diving headfirst into one of the deepest rabbit holes of my life: SINAD chasing. Before I knew it, I was buying every SOTA amp I could find and selling my old gear. With amps and DACs, it's easy—just compare the measurements.

But speakers? That’s where it got complicated. Thankfully, ASR started reviewing more speakers, helping clarify what to buy next. However, budget and existing gear made it tricky. I already had speakers I believed were excellent because everyone said so—except there were no reliable measurements to confirm it.

Determined to get some clarity, I teamed up with others from the German community and sent a speaker off to the USA for testing. That speaker was this one:


Well, not exactly this model—it was actually my surround speaker from the same NuVero series. Shipping my 70 kg NuVero 170 was obviously out of the question, but since the designs and drivers were very similar, we figured performance would be comparable.

After reading that review, reality hit: my speaker wasn't as perfect as I'd convinced myself. What does a true SINAD and linearity chaser do next? Exactly—I visited my local hi-fi shop, auditioned KEF and Genelec, quickly dropped Genelec (because I wanted passive), and settled on KEF Reference 3 Meta. I immediately sold off my entire Nubert system.

But after living with the KEFs for a year, I noticed something fundamental. Coaxial speakers like the KEFs have limited spatial imaging, especially in smaller rooms. They sound focused and clean, almost like listening directly to near-field studio monitors. Minimal early reflections, yes, but the room never felt truly filled.

This got me thinking about my Nuberts again—especially after looking at their radiation patterns. The magic, it seemed, lay in their incredibly broad horizontal dispersion, filling the room effortlessly even into the high frequencies.

Nubert Nuvero 60 KEF Reference 1 Meta (very similar to Reference 3 Meta)

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To confirm my suspicion, I repurchased my old NuVero 70 speakers (no typo!). With their smaller baffles, dual BMR drivers, and a low 1900 Hz tweeter crossover, they produce a wide, live, and immersive soundstage. It's vibrant, natural, and what my ears instinctively expect. Sure, they're not flawless—they can sound overly bright, a bit undefined, and far from perfectly linear. But hey, that's why we have Dirac, Audyssey, and EQ, right?

Here's my point: chasing absolute linearity in speakers is like obsessing over SINAD in amplifiers—past a certain threshold, it becomes meaningless. What's the use of a laser-focused, super-linear speaker in a cozy living room?

Interestingly, this impression isn't just anecdotal. Research by Floyd E. Toole has shown that speakers with wider and smoother off-axis response tend to be preferred by listeners, especially in typical living rooms. Even when the reflections are uneven, they are still preferred over a narrow but clean reflection profile.

Room size matters a lot. In a smaller room (~18 m²), narrow dispersion speakers like KEF Reference, MoFi, or Genelec may disappoint, while broad dispersion speakers like Nubert truly shine. In larger rooms (30+ m²), the opposite might be true, as wide-dispersion speakers could sound overly reverberant.

Now I'm sitting here with two completely opposite setups: KEF Reference + KEF R3 vs. Nubert NuVero 70 + NuVero 30, both powered by KC92 subs. I'll likely keep both and rotate every few months. Maybe that's exactly the variety we audiophiles need—to keep things fresh, avoid endless gear chasing, and stay grounded.

Thanks for reading!
 
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A related thing I've been wondering lately is whether it's the early reflections off of surfaces which give the impression of width of a sounstage.

Much like if you look into a mirror at an angle sideways your field of view is increased and it "appears" that the image is coming from a wider spot "behind" the mirror. Maybe same thing happens with audio reflecting off the side walls.

Although I do know that direct sound is the most dominant so maybe it's all just a bad analogy which doesn't apply to audio but I'd love to learn if something like this has been explored in the past.

I remember Dr. Toole said that if you remove floor reflections the preference goes down, maybe we have evolved to expect some reflections and when missing they make it sound "unexpected" even if more technically accurate.
 
In a concert hall or a club there are sound sources on the stage and a reflected sound field. Acousticians and the historic architects designed for that sound field that varies by seating location and how filled the hall is by sound absorbing bodies and clothing.

Then we have many kinds of microphones with their nonlinearities and placements that capture that sound field. They are brought into an often live-end/dead-end recording and mix room. With dead walls, floors, side walls, and back walls, no parallel surfaces, and control for bass, the sound is dominated by direct from the speaker. If it is not classical, and even sometimes in classical, the mixers add processing including synthetic reverberation.

It may not be practical in a home, unless someone designed and expensive home theater, or you are listening outdoors, but as you say, once a speaker radiation pattern gets in a specific room, room EQ only goes so far.
 
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Room size matters a lot. In a smaller room (~18 m²), narrow dispersion speakers like KEF Reference, MoFi, or Genelec may disappoint, while broad dispersion speakers like Nubert truly shine. In larger rooms (30+ m²), the opposite might be true, as wide-dispersion speakers could sound overly reverberant.
Interestingly in my also quite small listening room it is exactly the opposite for me, I prefer rather narrow radiating loudspeakers, it would be interesting to now how much that preference depends on the room acoustics, listening distance and individual taste/preference.
 
A related thing I've been wondering lately is whether it's the early reflections off of surfaces which give the impression of width of a sounstage.

Much like if you look into a mirror at an angle sideways your field of view is increased and it "appears" that the image is coming from a wider spot "behind" the mirror. Maybe same thing happens with audio reflecting off the side walls.

Although I do know that direct sound is the most dominant so maybe it's all just a bad analogy which doesn't apply to audio but I'd love to learn if something like this has been explored in the past.

I remember Dr. Toole said that if you remove floor reflections the preference goes down, maybe we have evolved to expect some reflections and when missing they make it sound "unexpected" even if more technically accurate.

In my experience, it's kind of the opposite. Room reflections muck up the illusion of a soundstage in the recording. The illusion of a soundstage requires that we be able to suspend our disbelief that we're in our acoustic space and listening sound sources in the spots where the speaker are and instead feel like we're in the acoustic space of the original recordings and the the instruments we're hearing are spread in front of us at locations forward and backward, left and right.

Most importantly, that requires a recording that is make with the intent to capture the sound of instruments in a specific acoustic space -- that is, a soundstage. Most recordings of popular music don't have a soundstage. They're kind of multi mono iso recordings pan potted into stereo locations with reverb and/or delay added. You can put 'em in a room and listen to the bounces off the wall and imagine a wider "soundstage" or load 'em up with special phase and other effects to create something "immersive" out of just a 2 channel playback of a recording that wasn't make with an intent to capture a soundstage in the first place. In cases of those recordings, you're really doing "heroic" things to impose an illusion of a recorded space the experience, so sound bouncing off walls in the listening space, phase effects processing, the interchannel phasiness of vinyl playback, people do all kinds of things to impose a local illusion of a bigger, wider, soundstage on this iso, multi mono, pan potted "stage" recordings.

If you take a recording where the intent was to capture the sound of instruments and a performance in the original acoustic space and reproduce that in two channel playback -- mostly now we're talking about older and specialty classical recordings, which, when the idea of a "soundstage" entered the audiophile lexicon, were basically the only kind of recordings the then-audiophile community cared much about -- and you play it back in a local acoustic environment full of flutter echo and reflects sound arriving at your ears at relatively high levels in moderately close temporal proximity to the direct sound, and you're in a relatively small space so sound is reaching the right ear from the left channel much quicker than it would have in the original space, etc., you wind up experience a lot of ambiguous localization cues, between the illusory ones on the recording that you're trying to isolated, and all the ones going on in the local room.

It really comes down to what kind of music people like to listen to and what ways they like to listen to it. If you're listening to anything from Miley Cyrus to Led Zeppelin in a common living space, you may wind up with a pretty different set of preferences and even experiences than if you're listening to minimally miked classical recordings in a dedicated listening space.
 
Interestingly in my also quite small listening room it is exactly the opposite for me, I prefer rather narrow radiating loudspeakers, it would be interesting to now how much that preference depends on the room acoustics, listening distance and individual taste/preference.

Yeah, you know, when it comes to preferences, while a preference scatter plot of similar people might have a kind of dense grouping around a particular set of characteristics, it is still really pretty scattered, there are people with preferences that differ from that center group, and there can be a fair number of difference preferences and the sonic characteristics they prefer can be pretty different from the mean.

For a product developer, I understand why quantifying with most commonly preferred characteristics can be valuable in creating a widely popular product. But I don't understand why any of use as individual listeners really cares what is most commonly preferred. It's not really a useful metric for any individual, who might have very different preference from the mean, which, as not note, may relate to anything from room acoustics, musical preferences, cultural differences, whatever. To me as a listener -- and not a product developer -- most commonly preferred isn't very useful information.
 
Thank you all for your input!

What I keep wondering, based on all the responses above: have any of you tried the opposite of your current setup?

I realize this is easy to suggest but harder to implement—getting your hands on such speakers often means jumping €/$1000+ in budget. Still, my point stands: according to Toole’s research, wide-dispersion speakers generally outperform narrow or controlled-dispersion designs in terms of perceived sound quality.

That lingering uncertainty is exactly why I’ve decided to keep both of my speaker systems. In fact, I think I’ll switch back to my KEF Reference 3 Meta from the Nubert nuVero 70 for now, just to long-term test my statement.

At the heart of this thread lies one key question:
What kind of early reflections do people actually prefer?

From where I stand, the evidence points toward early reflections that include high-frequency content being more pleasing. After all, no real-world instrument—or anything our ancestors heard—had narrowly focused dispersion aimed solely at a sweet spot. Environments with suppressed reflections are more akin to dry studio rooms or headphone listening. Some people like that, and that’s totally fine. But for me, it's clear: early reflections with rich frequency content feel more natural and engaging.
 
Here's my point: chasing absolute linearity in speakers is like obsessing over SINAD in amplifiers—past a certain threshold, it becomes meaningless. What's the use of a laser-focused, super-linear speaker in a cozy living room?
Well, yeah.

Not to mention, what are you doing in that room? Do you move around or sit still. Are you alone?

And what are you accustomed to?

Look at it from another point of view: What are your preferences relative to the central tendencies of the published statistical preference tests?

It's complicated. The measurements are useful but we are all subjectivists in the end.
 
It's complicated. The measurements are useful but we are all subjectivists in the end.

Ha ha ha. I feel the same. I’m waiting to see how much barking will happen for the above :)

Back to the topic at hand, somehow i prefer wider dispersion speakers, narrow dispersion not so much. During my shopping period a few years ago, i liked the ATC50/ATC100 that i auditioned, but didn’t enjoy the Perlisten s7t. i realised later that the Perlisten measured pretty flat but had very controlled narrow dispersion.
 
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That lingering uncertainty is exactly why I’ve decided to keep both of my speaker systems. In fact, I think I’ll switch back to my KEF Reference 3 Meta from the Nubert nuVero 70 for now, just to long-term test my statement.
A few questions since you have both.

Nubert is significantly brighter, have you tried EQing Nubert to match the Kef in brightness or vice versa? They are about 2-3 dB brighter that Kef starting from the midrange.

How much have you experimented with placement and orientation. Turing the Kefs outwards should increase the amount of reflected sound vs direct sound. At the same time you might want to get the speakers slightly closer/further to each other to change the amount each of your each hears from each speaker. The Nubert radiating much wider, your left ear probably hears more from the right speaker with the Nubert than with the Kef.

All of this makes me question cardioids since they narrow down radiation in the midrange. But maybe narrower midrange compared to non cardioid but wide treble is the best characteristic. Though I do think there's a large degree of personal preference/use.
 
What I keep wondering, based on all the responses above: have any of you tried the opposite of your current setup?
Of course, I have several 3-way loudspeakers in my collection with wide radiation 2" mid and 0.75" tweeters, commercial and one even designed by myself:

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At the heart of this thread lies one key question:
What kind of early reflections do people actually prefer?

I found an interesting paper titled "Effects of loudspeaker directivity on perceived sound quality - a review of existing studies" by Evans et al (JAES 2009). The paper is a free download. From that paper:

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This is the key take-away from the conclusion:

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FWIW I also re-read what Toole had to say about the matter (Chapter 7.4.2 in his book, which references his 1985 study). It compared 3 speakers - a Rega Model 3, KEF 105.2 (both speakers with broader but uneven directivity) with a Quad ESL63 (narrow but smoother directivity). The speakers were placed in a listening room with absorptive treatment on the front wall, effectively converting the Quad from a dipole to a semi-monopole. Toole does not explicitly point this out in his discussion. Conclusion: listeners preferred the two monopoles over the Quad which he deliberately crippled, even though the directivity of both monopoles was uneven.

However, an even more important determinant was the recording. As he says, "Early lateral room reflections, to the extent to which they were manipulated by loudspeaker directivity, seemed either to be neutral-to-beneficial factors in pop/rock style recordings and in monophonic listening. In classical recordings with substantial uncorrelated left-right information, the effects are not clear".

There is a school of thought on ASR that asserts that "the soundstage is in the recording" and therefore we want narrower directivity speakers with more room treatment to attenuate reflections so that we can hear the recording directly. I can find no evidence for this assertion. In fact, Toole discusses in the same chapter the effect when this school of thought is taken too far - the sound is headphone-like, i.e. sounds like it is in your head rather than around you. If you have evidence for this kind of approach, I would very much like to read it - but for the time being, I am dismissing it as being unsupported by evidence.

My conclusion from reading all this: the question of "listener preference", as always, can be broken into two:

1. What do studies say about listener preference of the general population? My answer: there are no definitive studies that prove that wider directivity is preferred over narrower directivity, although it is fair to say that some reflections are preferred over none (i.e. headphones).

2. What is your actual preference? As JJ keeps saying, your preference is your preference, and it can not be argued with. But your preference is not generalisable to others.
 
1. What do studies say about listener preference of the general population? My answer: there are no definitive studies that prove that wider directivity is preferred over narrower directivity, although it is fair to say that some reflections are preferred over none (i.e. headphones).

2. What is your actual preference? As JJ keeps saying, your preference is your preference, and it can not be argued with. But your preference is not generalisable to others.
There's a third case, that people don't know what they like.
It sounds weird but I'll explain.

Most of us involved in a hobby usually have either strong opinions and views, some have little time, some don't have the means to try or go around listening.
Some have not even been in a venue to hear the real deal.
So there's an internal excluding based on the above which is far, FAR for useful when one wants to form a preference.

Example, me. Would I know my strong preference towards soffit-mounted mains monitors in treated room if I have never been in a studio? Nope.
Do I use this preference to come close at home? Yes and no, as at least for my dedicated I like to play around, and soffit mounting prohibits that.

Regardless, I do know for myself.
And that's my conclusion, people should try anything, go around and listen without prejudices (apart from silly stuff of course)
Narrowing without knowing is working against us.
 
There's a third case, that people don't know what they like.
It sounds weird but I'll explain.

Most of us involved in a hobby usually have either strong opinions and views, some have little time, some don't have the means to try or go around listening.
Some have not even been in a venue to hear the real deal.
So there's an internal excluding based on the above which is far, FAR for useful when one wants to form a preference.

Example, me. Would I know my strong preference towards soffit-mounted mains monitors in treated room if I have never been in a studio? Nope.
Do I use this preference to come close at home? Yes and no, as at least for my dedicated I like to play around, and soffit mounting prohibits that.

Regardless, I do know for myself.
And that's my conclusion, people should try anything, go around and listen without prejudices (apart from silly stuff of course)
Narrowing without knowing is working against us.
I believe that’s true for many of us.

As for me, I’ve reached a point in life where, with all the experiences and baggage I've accumulated, I know for sure that I gravitate towards a dead, dampened sound. I believe this suits my extremely varied taste in music, and in my experience, it makes everything on my playlist sound great to me.

I do recognize that many people prefer the liveliness of a room’s acoustics, and that many love dipole speakers, which can sound really engaging and satisfying, especially with certain types of music that suit it. It can even bring back memories of live music experiences. Personally, I think that kind of sound works well for those specific moments, but I’ve found that I grow tired of everything sounding "live" after a while. And as I mentioned earlier, I don’t think it works well for certain genres that I also enjoy.
 
I believe that’s true for many of us.

As for me, I’ve reached a point in life where, with all the experiences and baggage I've accumulated, I know for sure that I gravitate towards a dead, dampened sound. I believe this suits my extremely varied taste in music, and in my experience, it makes everything on my playlist sound great to me.

I do recognize that many people prefer the liveliness of a room’s acoustics, and that many love dipole speakers, which can sound really engaging and satisfying, especially with certain types of music that suit it. It can even bring back memories of live music experiences. Personally, I think that kind of sound works well for those specific moments, but I’ve found that I grow tired of everything sounding "live" after a while. And as I mentioned earlier, I don’t think it works well for certain genres that I also enjoy.
Yep.
I strongly believe that my "sound" preference has to do with my music.
Environmental clues and venues are often embedded in classical so there's little need for early reflections (dead front wall and treated ceiling is the most improving things ever in my room, sides are far)

But that's narrowed down to me, alone. Can't apply it as a general preference, nor discredit other approaches.
 
Interestingly in my also quite small listening room it is exactly the opposite for me, I prefer rather narrow radiating loudspeakers,
I second this when I listened to your system.
it would be interesting to now how much that preference depends on the room acoustics, listening distance and individual taste/preference.
IMV it depends on the recording. If it contains spatial information then additional room reflections destroy the existing 3D soundstage. In the other case those reflections create an artificial 3D soundstage which sounds better than no soundstage.
 
Yep.
I strongly believe that my "sound" preference has to do with my music.
Environmental clues and venues are often embedded in classical so there's little need for early reflections (dead front wall and treated ceiling is the most improving things ever in my room, sides are far)

But that's narrowed down to me, alone. Can't apply it as a general preference, nor discredit other approaches.
That pretty much sums up how I feel about it. When I listen to live recordings, I don’t feel like I’m missing anything. Sure, would those recordings sound even more convincing with a lively room and a pair of dipole speakers? Probably. But I’d consider it more of a coloration, not something that was originally recorded.

Speaking of room treatment, I’m reminded that I should probably do something about my ceiling to improve the sound even more. Then again, I’m happy with how it sounds now. Given the effort it would take, and I've already renovated the entire house once, I’ll probably never get around to it -unless my wife decides we need to change the ceilings throughout the house. :)
 
By the way I just wanted to say what a lovely, interesting and civilised discussion despite some different opinions, that's how it should be and makes ASR such a great place to be. :)
 
It's about getting back to front refractions ratio to be good which is not possible in the small or medium sized rooms so you instead go for the minimum time value between them (close to the wall behind them). In full treated over dumped room it will sound unnatural same as with closed back headphones but if time domain and delays are kept low you can emulate space reverberation of pretty much any box (which room is). Future more you can adjust bandwidth to the distance which is very old way to do it (and not easy to find as effect today but still manageable). As long as you live on earth minimum is flore refractions to our brain to even remotely consider it as real and you can't beet mileniums of evolution (that's why preference without it goes down).
 
It is easy to experiment and see what a person likes with respect to this issue. Toe speakers out more, more sidewall reflections. Sit closer, fewer, further away, more. I've done this, a lot in the past.

I can get a wider sound stage with more sidewall reflections, no doubt. The cost is more distortion, and more vague placement in the sound stage. I can get wall to wall sound for some recordings in the triangle spot, but I can blow out the walls and image to the ceiling if I bring in more sidewall by toe out AND more distance from the speakers.

For speaker choice, given that my MLP is 2x the distance from the less used triangle position (12' versus 6'), I went with something with narrower horizontal dispersion. This gives me quite accurate triangle results, but keeps the distortion from reflections more under control from 12' away. If I were pulling the speakers 4' further into the room, I would have gone with a wider dispersion design, most likely.

And figuring out dispersion to give me what I wanted in my particular room, that was an issue compared to looking at sweeps of speakers. Definitely. But once figured out, it's pretty easy to do it in the future for any room... for my tastes in playback.
 
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