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omnidirectional loudspeakers = best design available

As I mentioned earlier, I absorb the contralateral reflection from my left speaker, because my right wall is too close. So the idea of directional speakers allowing for a smaller room is rather suspect to me.

I suspect the asymmetry of your room is your issue, not contralateral reflections in general. I've yet to encounter an issue with them, but I've yet to try it in a room like yours. And it sounds to me like you've found an effective solution.

This Subject and subsequent conversation applies to some degree to Electrostatic Speakers as well, correct?

The short answer is, I think so. And as you can already tell, I have a longer answer in mind.

You see, imo yours is an excellent question because its implications reach far beyond electrostatics: Just how widely applicable is this subject and the subsequent conversation?

I think there is potentially significant common ground among omnis, dipoles, bipoles, other polydirectionals, cardioids, constant-directivity narrow-pattern monopoles, well-behaved wide-pattern monopoles, Live-End/Dead-End, Reflection Free Zone, multichannel upmixing, and doubtless other approaches.

Their conceptual common ground, subject of course to appropriate set-up, is imo articulated well by oivavoi:

FWIW, my own preference is to listen to wide-dispersion speakers (in the future possibly omnis) in the near-field. That way one gets much late indirect sound which is similar to the direct sound, but the direct sound still dominates the perception and creates good stereo images. [emphasis Duke's]

Imo what all of these different approaches have in common is the pursuit of “much late indirect sound which is similar to the direct sound, but the direct sound still dominates the perception and creates good stereo images.”
 
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I don't see any inconsistency with what I've previously said. I interpret Toole as basically making the same point, albeit more eloquently. I'll counter your take with my own emphasis.

"Which, of course, is quite impossible with only two channels! What we hear is only hints of what might have been, as tweaked by recording and mastering engineers. Nothing approaching the original sound field is captured, stored or reproduced. An active imagination is required, and that very likely is strongly individualistic. The problem is the "system" (stereo), not the loudspeakers. This does not mean that music cannot be extremely pleasurable, but the expanded "circle of confusion", if reality is the goal, is not a circle at all. It is a dead end, so long as we stick with two channels. Let the flames begin . . ."

My point is that Omni speakers can't take music recorded and mastered for conventional stereo reproduction and recreate or "restore" it accurately to the original live performance. No speakers can, including conventional forward firing loudspeakers.

Right, we both just got done saying that. Not sure why it would have to be repeated. Seems we are essentially on the same page there.

That is if we are agreeing on that basic, academic point.

But though "perfectly accurate recreation" may be impossible, it seems we can still talk about "closer" and "further" from recreating the original sound of instruments and voices contained on a recording. Remember, breaking the original sound down in to tiny microphone vibrations, on to electrical signals, then to digits, to an analog signal to speaker drivers...it's all an illusion, right? It's never actually "real" so we can talk about which version of the illusion gets closer to the effect of hearing the live sound. And then we are right back to the pertinence of whether an omni can do as well, or better, in any sense, than the average front firing speaker. As I've said, in my experience, the omnis did it better.

And it gets down to niggly details as to what one would accept as getting closer to "reproducing the experience produced by the original live instrument/voice." I recorded myself playing acoustic guitar parts that me and my other musician pals always loved. So when one of my musian friends would come over sometimes I'd take the opportunity to do the live vs reproduced test with the speakers I had at the time - he'd play the part I'd recorded, sitting between the speakers with me at the listening position eyes closed, and then I'd play the recording, just to compare and analyze the difference between live vs reproduced. The guitar recording played through the omnis sounded most like the real guitar in the room.

Further, my son used to practice sax both in the basement and sometimes in my listening/multi-purpose room. So I was used to hearing that sax playing from outside the room, just a little down the hall. I wanted to see how close I could re-create that and recorded him practicing. I'd play it back on every speaker I owned over the years and NOTHING sounded more like the real thing coming out of that room than the omnis. It just sounded like it did, indeed, recreate the "live performance" that I was so used to hearing. And as I mentioned, I fooled a few people who thought it was my son playing sax in another room.

So if we are talking about whether a speaker can "recreate the live performance" - the sound of the live instrument being played in front of the mics, rather than what the mic heard - I don't see how my direct experience testing this phenomenon doesn't bear on the question. The omni I owned did better than all the forward firing speakers I owned. Doesn't mean a forward firing speaker doesn't exist that might do better. But the omni sure seemed to get there more effortlessly than the many speakers I've owned.


People who state that this magic is somehow possible either don't understand what they're talking about or are drinking their own cool aid.

Possible like what? Like being able to recreate such a close approximation of the live sound that it sounds live, and can even fool people?
Actually: been there, done that. No cool-aid was necessary; only experience testing the hypothesis. From outside the room it was close to perfect. From inside my room at the seated position it was less perfectly convincing, but BETTER than the forward facing speakers. And since no one is arguing about "perfect" but rather if one may get "closer" to the live sound, that is pertinant. Have you actually tested these things yourself? I do get the feeling you are speaking more from theory than experience (?)


Alternatively, the benefit of conventional forward firing loudspeakers is that you get to listen to the music through the same type of setup that it was mastered and approved on by the artist who created it. Being that most music is made in a studio this way you have a much higher chance of hearing it as it was intended to be heard by the artist who created and released it. Throwing Omni into that chain adds permanent embellishment to the entire system.

Again: That's a sweeping generalization. There's nuances here.

The "embellishment" you credit to the omni no doubt are the room reflections. But in the big picture, that's the case with virtually ALL speakers, which interact with the room.

And rooms are different. So it's going to depend on the speaker type, the type of room (size, how live/dead surfaces), listener position to the speaker (far or nearfield for direct sound?).

You could play an omni in an acoustically "dead" room, and even include listening more in near-field, and you'll be percieving predominantly direct sound. Whereas you could take a forward firing loudspeaker in a very "live" room, sit further and soak in much more "embellishment" by way of room reflections than the omni set up described.

In fact...I've done just that. I can make my room much more dead than the average room, and I often sat very close to my omnis, and the sound was more precise, direct and accurate sounding than plenty of forward firing speakers I've listened to in big, live rooms with lots of room sound.

So this sweeping "omnis do this/forward firing speakers don't" thing you've got going in terms of coloration is, I suggest, just too simplistic.

And as I said, your claim the omnis won't sound "as the artist heard it" 1. goes down the rabbit hole, since you don't have the room and speakers the artist used. 2. Is someone's forward firing speaker set up in their live room listened at a distance automatically "less embellished" than my omni in my more dead room listened nearfield? Is he in a position to say "YOU opted for embellishment of the sound by choosing omnis. I chose an accurate pair of forward firing speakers, so I'm the one hearing the signal with the least embellishment!" ? I don't see how, if by "embellisment" one is simply referring to the audible addition of room sound. And, as I mentioned, having actually compared the omnis many times to forward firing speakers, I did not hear any major departure in the details of the mix or any of the artistic elements.
 
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He [Toole] has certainly used both stereo and multichannel in his own listening setups over the years, so why do you think he would not have formed a comparison-based opinion? And of course he can turn off an upmixer any time he wants.

Yap, of course. What I meant was that he hasn't performed systematic blind listening tests with others on stereo vs multichannel. So in that way his preference for multichannel over stereo is based on his own subjective listening impressions, just like Linkwitz' preference for the reverse is based on his subjective impressions. The difference is that Toole's preference is broadly in line with what subjects have reported in blind tests (with exceptions, as always). But like the discussion here shows, there is no guarantee that one's own indvidual preference will be in line with the statistical average in such listening tests.
 
BTW, I'm somewhat shopping for a decent omni for my garage setup, but nothing super expensive. The Revel M105s are oddly not wide enough dispersion for the amount of pacing around I do while working out. Any measurements out there of reasonably priced omnis? I was looking at Ohm, but it seems they're not well regarded here. I've heard and enjoyed the giant $200,000 MBLs, but no way can I afford even 1/10th of that for a secondary system. Morrison audio has been brought up a few times, but they're still too expensive(from what I've seen). Maybe if I can find a really good used price, but still, I can't find good measurements, and I'm super hesitant to buy speakers sans measurements these days.

Never heard them, but for such a setup I would probably look for a set of Linkwitz plutos with subwoofers. Either used, or attempt to build a set yourselfs. Plans are now available for free. Measurements are available, decently omni up to a certain frequency. Alternatively a pair of Apple homepods or Samsung R7s for simplicity.
 
I would say no. At least with the electrostats I've heard(ML), they have more in common with a narrow dispersion horn speaker than they do an omni speaker. The electrostats I've heard throw a super clear and precise, yet super unstable image, which is the same as what my JTRs do, and it's the exact opposite of what a good omni will give you.

I get why you asked that, though. They do seem to be getting somewhat lumped together here, and I'm not sure I totally understand why. I think @Duke has actually made some really great points re: min/maxing early vs late arriving reflections, but (at least based on what I've heard) his points are good arguments in favor of dipoles, not omnis.

BTW, I'm somewhat shopping for a decent omni for my garage setup, but nothing super expensive. The Revel M105s are oddly not wide enough dispersion for the amount of pacing around I do while working out. Any measurements out there of reasonably priced omnis? I was looking at Ohm, but it seems they're not well regarded here. I've heard and enjoyed the giant $200,000 MBLs, but no way can I afford even 1/10th of that for a secondary system. Morrison audio has been brought up a few times, but they're still too expensive(from what I've seen). Maybe if I can find a really good used price, but still, I can't find good measurements, and I'm super hesitant to buy speakers sans measurements these days.
https://teenage.engineering/products/od-11
 
I actually proposed to Don Morrison to send one of his speakers to Amir. Still waiting on my pair to get finished, but when they do get finished I have thought about making Amir a stopgap, if he's interested and they haven't been measured by then.

Should be so very useful to have a full set of measurement for those speakers!
 
Thanks! Never would have found that on my own.

Not omni ofc, but the BMR Philharmonic has c. 160° dispersion out to 20kHz. Could be one to consider?

1610199775739.png
 
The most important aspect of home audio reproduction, is the role of the loudspeaker. Omnidirectional loudspeakers produce the most realistic musical soundstage in the home; however they remain the least understood by the public and audiophools alike. The superiority of the design is easily heard when in person, and when measured, particularly in the off-axis domains both vertically and horizontally. Live music and therefore sound propogation happens omnidirectionally, and is how our ear-brain mechanisms have evolved to understand sound. 98% of loudspeakers are designed incorrectly; yes you read that right and it's easily verifiable w/ measurements. Most loudspeakers beam the sound toward the listener in a totally unnatural way, and suffer what are called 'lobing effects' and again, are easily measured particularly when you start to move off-axis. (marketing department of companies don't measure nor publicize these measurements once out of the sweet spot, because they are horrible). These concepts have been substantially explored by the late Sigfried Linkwitz of Linkwitz Labs; I believe all his research and papers are available at the website. Further explanation is available at the website of Morrison Audio loudspeakers, highly recommended. It is important to note, that there is major distinction between polydirectional speakers, and omnidirectional.

Makers of omnidirectional loudspeakers include:

Ohm Acoustics
German Physiks
MBL
Mirage (out of business; still available used)
Linkwitz Labs (LX Mini is a hybrid omni)
Duevel
Morrison Audio

I would encourage anyone who is serious about music, and wants the most realistic soundstage in their home, to pursue omnidirectional loudspeakers. Contrary to audiphool misunderstanding, they actually excite the listening room LESS than conventional speakers, and require LESS or no special room treatments.

Rules for making a great omni:

-design should be 2-way. Single driver is inadequate; 3-way is unnecessarily complicated
-woofer driver should face UP, with lots of room behind it to reduce or eliminate back wave from radiating back out the cone
-tweeter should also be facing UP
-both woofer and tweeter should be place immediately together, and with dispersion caps or guides to disperse the outgoing sound both vertically and horizontally
-cabinet should be totally inert, as measured by accelerometer
-speaker should be able to be driven using either a passive or active crossover
-inputs should be Neutrik Speakons; Benchmark Media has measured conclusively the lowered distortion of Speakons compared to binding posts (spades or bananas)
-listening height of drivers should be at listener's seated ear level OR LOWER

This considered, the 2 best omni designs, and therefore the 2 best loudspeaker designs in the world right now, are from Duevel in Germany, and Morrison Audio in Canada. All others on the list are "honorable mention".
Responding as someone who just dove into the market for hi-fi audio, I was stunned and perplexed that all the speakers I listened to sounded so artificial in how they inhabited space - yet, all of the speakers I listened to were highly reviewed by so-called experts. I just felt like the sound and experience of the music was colored by the speakers themselves, and was missing (without knowing it) I guess a more psychoaccoustically natural reproduction. The other day though, frustrated with my experiences so far, I went to a local big box store, and when nice young lady let me hear some deftech dipole speakers - it was an instant revelation. The music extended out into space in a way that felt far more natural to my ears, it was not just flavored sound coming from a box as much anymore. It felt like the music enveloped the space I was in, uniformly and much more coherently. Very cool indeed. And then I came across this post somehow, which helped me to connect the dots of what that experience was probably about... It explains why all the (directional) speakers I have listened to for music so far sound fundamentally flawed to me unless they have been in- or over-ears. For creating music with my electric guitar for example, directional speakers are great and the right choice, but not for open-space music reproduction, not to my ears at least.

I would like to audition or even purchase w/out audition a pair of Duevels, but it doesn't seem like there are any dealers at all in the US?! Could anyone provide some guidance on US dealers of omni speakers (besides Ohm, which I already about)? TY
 
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Responding as someone who just dove into the market for hi-fi audio, I was stunned and perplexed that all the speakers I listened to sounded so artificial in how they inhabited space - yet, all of the speakers I listened to were highly reviewed by so-called experts. I just felt like the sound and experience of the music was colored by the speakers themselves, and was missing (without knowing it) I guess a more psychoaccoustically natural reproduction. The other day though, frustrated with my experiences so far, I went to a local big box store, and when nice young lady let me hear some deftech dipole speakers - it was an instant revelation. The music extended out into space in a way that felt far more natural to my ears, it was not just flavored sound coming from a box as much anymore. It felt like the music enveloped the space I was in, uniformly and much more coherently. Very cool indeed. And then I came across this post somehow, which helped me to connect the dots of what that experience was probably about... It explains why all the (directional) speakers I have listened to for music so far sound fundamentally flawed to me unless they have been in- or over-ears. For creating music with my electric guitar for example, directional speakers are great and the right choice, but not for open-space music reproduction, not to my ears at least.

I would like to audition or even purchase w/out audition a pair of Duevels, ....
Hi and welcome -- to both ASR and hifi! Let's hope you have some fun and learning in both realms.

Assuming 'deftech' is Definitive Technology, the only 'dipole speakers' of theirs, to my knowledge, are those two-faced, wall-mount surround sound speakers from a bygone era,

sr9040-rectangle-376.png


that are not actually appropriate for modern discrete multichannel music, but still sell well so guess what, they will still make them.


If they played those for you in dipole mode, not bipole, then they did you a disservice. You would have been hearing almost no direct sound whatsoever.

As for Duevels, I suggest you don't get carried away with dubious notions. Here is some information from earlier in this thread about what sort of dispersion from a loudspeaker is 'natural' in terms of resembling musical instruments and voices. It is NOT omni. https://www.audiosciencereview.com/...akers-best-design-available.19024/post-628313 I am not sure how technical you are: let me know if you get lost in translation.

The OP opened this thread with, “Omnidirectional loudspeakers produce the most realistic musical soundstage in the home” .... “The superiority of the design is easily heard” .... “Live music and therefore sound propogation happens omnidirectionally, and is how our ear-brain mechanisms have evolved to understand sound” .... “Most loudspeakers beam the sound toward the listener in a totally unnatural way” .... “they actually excite the listening room LESS than conventional speakers” ....

A lot of those claims don't hold up to scrutiny: omni speaker reproduction is only ‘natural’, if live music is omnidirectional. It isn't. So omnidirectional speakers are not doing it ‘the natural way’.

cheers
 
Might as well kill 3 birds with one stone.

If I stand in front of you and talk, my voice is not anything like omnidirectional, and if I play a violin or guitar or clarinet while standing there, its music is also not omnidirectional, not even close. So, if an omnidirectional speaker is placed where I am standing and plays a recording of my speech and instrumental playing, and redirects all the sound omnidirectionally, that loudspeaker is performing a gross reproductive inaccuracy. An act of high unrealism.

The whole idea that omnidirectional playback is correct, or ideal, is a myth.

Here are the actual directivity vs frequency plots of voice and various instruments, © Toole:

View attachment 104251

The fact that they are not all the same means that no one loudspeaker can be perfect at reproducing all their directionalities. However, in broad and general terms, the speaker type that does best at reproducing the directionality of some of the most critical original sources such as voice, string and wind instruments, is ..... your typical front-firing loudspeaker that trends to omnidirectional in the bass!

(P.S. An omnidirectional speaker is a flat line on the zero axis at the bottom of the above chart. Pretty bad eh?)

So, if we compare the human voice directivity curve, above, to some forward-firing loudspeakers © Toole:

View attachment 104252

Again, imagine an omnidirectional loudspeaker on the above graph as a flat line on the zero axis. We can easily see that various conventional loudspeakers on the graph are far superior to an omnidirectional at reproducing something approaching the directivity of a human voice in a natural way. Furthermore, if we imagine adding the various other instruments from the top graph onto the bottom chart, we see the conventional loudspeakers even better at matching their directivities, and the omnidirectional even worse again. In fact, the omnidirectional is completely uncompetitive at the one feature that has been promoted as its natural advantage.

Thus we see that all the above arguments that idealise the directivity of omnidirectional loudspeakers, are based on a false premise, which changes all your conclusions.

Cheers

I know this is an old post, but it's a really good one. I've seen it mentioned many times on many forums that real instruments radiate omnidirectionally, and that's why omni speakers sound so natural. I don't know where this idea got started(one of the omni speaker companies?), but it seems to somehow be a very commonly held belief. Unfortunately, it's almost the exact opposite of the truth. Of all the radiation patterns, omni is without a doubt the least similar to the way most real sounds and real instruments in real life radiate.

Not saying omni speakers can't sound great. They can, and I hope to own a pair at some point for one of my systems. Omni speakers provide an unrivaled sense of spaciousness. Image is too diffuse, but that's countered by it being super stable. I could see them being the best for reproducing certain experiences (like being at a live symphony in one of the rear rows). They also work great when you want a good experience while being free to move around the room, and not be tied to a sweetspot.
 
I know this is an old post, but it's a really good one. I've seen it mentioned many times on many forums that real instruments radiate omnidirectionally, and that's why omni speakers sound so natural. I don't know where this idea got started(one of the omni speaker companies?), but it seems to somehow be a very commonly held belief. Unfortunately, it's almost the exact opposite of the truth. Of all the radiation patterns, omni is without a doubt the least similar to the way most real sounds and real instruments in real life radiate.

Not saying omni speakers can't sound great. They can, and I hope to own a pair at some point for one of my systems. Omni speakers provide an unrivaled sense of spaciousness. Image is too diffuse, but that's countered by it being super stable. I could see them being the best for reproducing certain experiences (like being at a live symphony in one of the rear rows). They also work great when you want a good experience while being free to move around the room, and not be tied to a sweetspot.

And yet some of the most uncannily real vocal reproductions came from my omnis. The ones where I could close my eyes and require very little effort to imagine real people are singing.

I agree there is some sloppiness in the idea that "voices and instruments radiate omnidirectionally." They do, but not with the same frequency balance at all angles.

Nonetheless...damn!...omnis are doing *something* right, to my ears.

As I mentioned before, I've got a recording I made of my acoustic guitar being played and no speaker has reproduced the sheer realistic sensation of my guitar manifesting in front of me in the room, than the MBL omnis I had. It was doing *something* realistic that no other speaker I owned is quite managing.
 
I know this is an old post, but it's a really good one. I've seen it mentioned many times on many forums that real instruments radiate omnidirectionally, and that's why omni speakers sound so natural. I don't know where this idea got started(one of the omni speaker companies?), but it seems to somehow be a very commonly held belief. Unfortunately, it's almost the exact opposite of the truth. Of all the radiation patterns, omni is without a doubt the least similar to the way most real sounds and real instruments in real life radiate.

Not saying omni speakers can't sound great. They can, and I hope to own a pair at some point for one of my systems. Omni speakers provide an unrivaled sense of spaciousness. Image is too diffuse, but that's countered by it being super stable. I could see them being the best for reproducing certain experiences (like being at a live symphony in one of the rear rows). They also work great when you want a good experience while being free to move around the room, and not be tied to a sweetspot.
Thanks Richard.

On the bit I made bold above, it might be worth mentioning that omnis create maximum playback of the sound of your room, so the spaciousness they create is the sense of the space of your room. If you want that in extremis, then they are a great choice!

But if we want a sense of the space of the performance venue, then we don't want that swamped by extreme playback of your room, and multichannel playback using speakers with prominent direct sound is a better choice. Backed up by good recording technique.

cheers
 
And yet *to my ears* some of the most uncannily real vocal reproductions came from my omnis. The ones where I could close my eyes and require very little effort to imagine real people are singing.

Only "real" omnis I've ever heard are the giant MBLs. My impressions were unfortunately almost exactly opposite of yours. I thought they sounded totally unnatural(and not like the real thing), but at the same time intoxicating and pleasurable in a weird way, as it was like being surrounded in the music. My brain found it totally weird that it was coming from 2 speakers in front of me. Totally unnatural sounding, but at the same time really cool :D. Erin's description of the Bose 901(not the bad tonality part) kinda reminded me of my experience with the MBLs. It's a sound that's hard to dislike, even though it sounds far from "real"(imo). I've heard Ohms too, but supposedly they're not true omnis.

That's the problem with subjective impressions, though. We hear the *same* speakers(not sure which MBLs you owned), but leave with totally opposite(though both positive) impressions :D.

Looking at the data, almost nothing in real life (man made instruments or in nature) radiates its full range omni-directionally. Likewise, from what I've seen, objects/instruments that only radiate high frequency are almost always more directional than objects/instruments that only radiate low frequency. Without changing the way we record and mix, and jumping to like 20+ speakers, it's simply not possible to get a setup that matches the radiation pattern of all objects and instruments. If your goal is to get something that is most natural(close to real life) "on average", you are going to want a speaker that gets more directional as frequency increases. Omni is the worst radiation you can choose, as it's the least similar(maybe something like Kii that beams down to 50Hz?) to real life "on average".

I'm still very interested in omnis though(never heard a Morrison, but want to), as I'm not always looking for what sounds closest to real life, but rather what sounds best for the material. A bit of both tbh. For me, I think it depends on the type of music I'm listening to as to whether or not I want a "most real" sound, or a "best" sound. For a lot of the music I listen to, there isn't really a most real sound, and the sound in my home sounds much better than it does live.

I do think there are situations where an omni speaker will give you the sound that most closely approximates a live event, but not because of the way the instruments themselves radiate, but rather the ratio of direct/indirect sound that reaches your ears in the live setting. For example, sitting at the back of a symphony hall, most of the sound you hear is indirect sound. If you're listening to a close miked symphony performance reproduced by speakers 10 feet away from you, an omni speaker will probably give you the sound that most closely approximates what you hear in the actual hall. Other performances where more of the venue is already in the recording, "real" will be most closely approximated by more directional speakers.
 
I had Magnepans for a few years. I kept getting annoyed/irritated with the way they sounded when I sat to listen critically. And I didn’t find the image stable at all. It shifted around with the frequency content in my recordings. Got on my nerves. But they sound cool when you play rock and are milling around the room.
 
@richard12511 I, too have multiple in-home, fully-set-up experiences of what you call "giant MBLs". Nothing special happened.
 
... all the speakers I listened to sounded so artificial in how they inhabited space - yet, all of the speakers I listened to were highly reviewed by so-called experts. I just felt like the sound and experience of the music was colored by the speakers themselves, and was missing (without knowing it) I guess a more psychoaccoustically natural reproduction. The other day though, frustrated with my experiences so far, I went to a local big box store, and when nice young lady let me hear some deftech dipole speakers - it was an instant revelation. The music extended out into space in a way that felt far more natural to my ears... It felt like the music enveloped the space I was in, uniformly and much more coherently.

Many year ago THE MOST universally respected researcher on this site, Dr Floyd Toole, chose bipolar Mirage M1 loudspeakers based on a) the results of controlled blind listening test conducted while he was Director of the National Research Council (NRC) in Ottawa; and b) how these particucular speakers sounded to his ears in his room. Quoting from page 190 of the Third Edition of his book, "Sound Reproductio: The Acoustics and Psychoacoustics of Loudspeakers and Room":

"Over the years, a parade of loudspeakers went through that room [his large listening room in his home]. and all disappointed. The room was an unforgiving critic of loudspeakers in which the direct and reflected sounds exhibited different spectra, and conventional forward-firing loudspeakers drew attention to themselves.... Then, in 1989, a new loudspeaker came onto the scene: the almost omnidirectional, bidirectional-in-phase "bipolar" Mirage M1. They performed well in double-blind listening test in the small NRC room, and also in this large one. They simply "became" the orchestra."

Dr. Toole subsequently became Vice President of Acoustical Engineering at Harman International and oversaw years of even more in-depth investigation into the relationship between loudspeaker measurements and listener preference. He is now retired and his home audio system consists of Revel Salon 2 loudspeakers plus rear-channel speakers, as he employs "tasteful upmixing of many recordings to embellish the sense of space" (page 193). One of the similarities between "tasteful upmixing" and bipolar (and omnidirectional) loudspeakers is that both approaches done well result in a spectrally-correct and relatively well-energized reverberant field. In other words, what Dr. Toole's system is doing today shares that common ground with what his Mirage M1's did back in the day.

Many of Dr. Toole's followers would be surprised to learn that he is quite open-minded towards bipolar and other multi-directional loudspeakers. Quoting from a fairly recent post of his on this forum:

"The well-behaved multi-directional speakers I have heard sound just fine, and are a viable alternative to forward firing designs."

So I suggest you not be dissuaded by those who tell you that the science is against bipolar and/or omnidirectional loudspeakers, because their favorite scientist is not.

Disclaimer: I used to manufacture (award-winning) bipolar loudspeakers, and may build bipoles again some day, and currently manufacture what might be called a variation on the theme.

I've seen it mentioned many times on many forums that real instruments radiate omnidirectionally, and that's why omni speakers sound so natural. I don't know where this idea got started(one of the omni speaker companies?), but it seems to somehow be a very commonly held belief. Unfortunately, it's almost the exact opposite of the truth. Of all the radiation patterns, omni is without a doubt the least similar to the way most real sounds and real instruments in real life radiate.

Imo a better argument for omnidirectional (and other multidirectional) loudspeakers would be that they do a better job of recreating the kind of reverberant field we would experience at a live performance. More specifically, that such speakers create a reverberant field with a more natural spectral balance, a more representative direct-to-reverberant sound ratio, and with the reflections arriving from directions and at arrival times which better support the illusion of a live event. Imo the "real instruments radiate omnidirectionally" sales pitch was probably the marketing department dumbing it down.
 
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I had Magnepans for a few years. I kept getting annoyed/irritated with the way they sounded when I sat to listen critically. And I didn’t find the image stable at all. It shifted around with the frequency content in my recordings. Got on my nerves. But they sound cool when you play rock and are milling around the room.

Not sure if you're responding to my point, but if you are, I don't disagree about your stability point. My point about image stability applies to omni speakers, not Maggies. Maggies ime are very much sweet spot speakers, but I can also understand why some might really like them.
 
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