Omnidirectional speakers

[tmuikku]

Yeah changing listening distance further / closer from speakers is kind of positioning adjustment on steroids in a way that all reflections change and their level to direct sound reduces. This is important listening experiment in multiple ways, first of it shows kind of "maximal" effects so that you can quickly scan the potential of the system in the room just by walking around, which also builds up listening skill. This could of course be further refined by changing speaker positioning as well for which you need the listening skill. Second, which I'm currently speculating, it ought to teach us about our hearing system, allow to understand it better. My speculation is about the transition I think you might have touched there, where perception of stereo sound changes from "flat" to "3D" thing, which seems to be what David Griesinger has been writing about in his studies as Limit of Localization Distance, and I've called it as audible critical distance on forums before knowing better. Mentioning this to avoid writing too long post here, you can search with that if you are interested

Point is, there seems to be a listening distance where perception changes and whats important it doesn't seem to be a sliding concept perceptually but quite distinct on/off phenomenon which makes it easy and reliable to detect, and it doesn't seem to be room or speaker dependent, but a property with our hearing system. Room and speakers are involved of course, but it seems to only change distance where the transition happens, and perhaps how stark the change is, if there is some sliding with it. On my setup, it happens within about one step.

Anyway, if it's the LLD and what Griesinger writes is true it is very powerful tool. First: it's relatively easy to detect in many situations, two: it should be common between all of us as we've evolved together, three: communication about stereo perception is meaningless/confusing unless everyone communicating knows about the transition and which side are we talking about, it's a connecting factor between unknown rooms and speakers anyone could relate to. Four, it helps you to understand better what you want to hear and if you know where the transition is you can change at will, or example some recordings work better on either side and personal state could want either. If you read Griesinger papers there is a lot of implications with the transition, which you can then utilize as logical tool to help understand what is it that you are hearing. This will tremendously improve listening skill, help you to connect written concepts to your perception of sound in your room. This is very serious stuff in a way, and very little talked about on forums or in general it seems. Saw a chance here to post about it so I took it

ps. this is mostly speculation by me based on limited set of circumstances including few stereo systems in few rooms and few friends, also some forum members in their own circumstances. So, I'd be delighted if you posted what's your stereo listening triangle size and your room size? Rough estimates fine. Thanks!

 

[Flaesh]

$500, what the heck.

It's 1/3 of Visaton Fontana kit https://www.visaton.de/de/produkte/hifi-surround-bauvorschlaege/2-wege-boxen/fontana/bauanleitung

Or about one pro coax like

Can’t do “soundstage and immersion” or whatever tests without lab supplies

Why not?
For example https://www.audiocheck.net/audiotests_index.php

 

[tmuikku]

I mentioned envelopment with respect to the Omni “sound”, but the initial more noticeable characteristic was the soundstage expansion in width and depth.



I just now moved the Omnis further out into the room, increasing distance from the rear wall, and first reaction was more envelopment—that’s what would be expected if I understood correctly.

Since the room is more long and narrow shape, maybe moving them closer together would add even more by reducing early side reflections? Obviously, there would be a trade-off in spatial imaging as left and right channels got closer together. I’ll try that next. I have been lax in trying more positions within the room.

Hi, sorry I just now noticed Duke was already on to it! When you are too far from speakers there is no envelopment as it's only one neural stream, a flat sounding "noise" as brain isn't picking the direct sound out from all sound in the room but handling them to you as one, doesn't think its important but just noise basically. When you get closer to speakers and notice the shift in perception, brain just picked up the direct sound out from the noise as to it's own neural stream, and now you have two neural streams: one your brain makes attention to, the foreground stream, and another as background stream, the envelopment. As the brain now listens to the direct sound you'd hear spatial cues from the recording you are listening to making it appear more wide and deep soundstage for example, while most of the local room sound is held back by your auditory system. Listening further out the brain doesn't hear the cues but localizes the "noise" into your local room, somewhere around the speakers.

Power with this is, that since you know where the transition happens, you can be sure that closer than this you ought to perceive envelopment and the spatial stuff from the recording, and beyond you cannot. Also engagement, and what not. Now it is possible to evaluate quality of the envelopment for example, as you can turn it on/off using the transition, moving a bit further or closer, it's like AB test in a way. You can now listen how wide your speakers need to be at for natural sound stage, too narrow can be too narrow, too wide can be too wide and so on. Take notes, change speaker position and do it again, compare notes to previous positioning. Fun stuff! It is possible to achieve just right "natural" kind of stereo representation: mono recordings can be very mono narrow and precise while your local room can seem almost muted, while big modern production very big and also enveloping and so on. If you listen far away everything would be kind of the same wide but hazy sound, not much spatial cues from the recording itself.

Similarly, if you wanted to listen effect of speakers being closer or further from front wall I think it is not possible to hear the difference if you listen beyond the transition because it's just noise basically, average of all early reflections in the room and it is a hazy blob of sound, direct or any individual reflection is not discernible from it by definition. It could change a bit, but not as much as happens when you just get closer to speakers. Basically, in order to evaluate what difference it makes to have speakers closer or further from a wall, you must know that there is the audible transition and always listen closer than that so that you are actually able to hear effects on direct sound, or effects on envelopment. If you listen further away, or do not know which side the transition you are listening at, it is not possible to draw conclusions about what you hear, it's just average sound, all reflections combined, you can't be quite sure what you are listening at and perhaps not hear a change as it's just averaged out. It is also easy to draw wrong conclusion.

Anyway, it is easy to have a speaker setup where the sound is hazy, so that listening position is beyond the transition, and there is nothing wrong with it, some people find it fine and the sound they are looking for. It's relaxing sound without too much details to it, your brain is not paying attention to it. It is also quite obvious some recordings were mixed this in mind and those can be quite annoying listened close up, with wild panning and stuff like that and can sound fabulous bit further away. As already said it is very advantageous to know the transition and then utilize for your benefit, listen either side as you feel like.

My text is a bit over emphasized to make good effect on reader. I hope everyone tried listening the stuff with their own setups, read some Griesinger papers and make their own conclusions about things. If anyone finds this interesting, or just crap then please comment, hopefully there will be discussion about the stuff. I think this is core to everything, key to be able to develop listening skill and to gravitate toward hifi sound at home, what ever it is to you with what ever room our speakers you have. Not just that but it is also core to discussion about things, a root so to speak, a key to common understanding: if not understood it is not possible to communicate about stereo hifi sound at homes without confusion as any participant could be talking the same thing but from either side of the transition and no-one understood each other and only confusion would ensue.

 

[jim1274]

Yeah changing listening distance further / closer from speakers is kind of positioning adjustment on steroids in a way that all reflections change and their level to direct sound reduces. This is important listening experiment in multiple ways, first of it shows kind of "maximal" effects so that you can quickly scan the potential of the system in the room just by walking around, which also builds up listening skill. This could of course be further refined by changing speaker positioning as well for which you need the listening skill. Second, which I'm currently speculating, it ought to teach us about our hearing system, allow to understand it better. My speculation is about the transition I think you might have touched there, where perception of stereo sound changes from "flat" to "3D" thing, which seems to be what David Griesinger has been writing about in his studies as Limit of Localization Distance, and I've called it as audible critical distance on forums before knowing better. Mentioning this to avoid writing too long post here, you can search with that if you are interested

Point is, there seems to be a listening distance where perception changes and whats important it doesn't seem to be a sliding concept perceptually but quite distinct on/off phenomenon which makes it easy and reliable to detect, and it doesn't seem to be room or speaker dependent, but a property with our hearing system. Room and speakers are involved of course, but it seems to only change distance where the transition happens, and perhaps how stark the change is, if there is some sliding with it. On my setup, it happens within about one step.

Between my experimenting with Omni placement and just this morning watching a video of a Griesenger lecture Duke sent me, a lot of the pieces of the puzzle fell into place and had a major “ah-ha” moment. I realized why the smaller Planet Omnis, that had been moved into the kitchen, sounded so bad. A long narrow (approx 10’ by 26’) highly reflective room was about the worst possible for Omni (too reflective overall and no way to minimize side reflections sufficiently). The best option there would seem to be a speaker with lower horizontal dispersion—my BMR Monitors with the wide horizontal dispersion ribbon tweeter is a bad match.

Anyway, if it's the LLD and what Griesinger writes is true it is very powerful tool. First: it's relatively easy to detect in many situations, two: it should be common between all of us as we've evolved together, three: communication about stereo perception is meaningless/confusing unless everyone communicating knows about the transition and which side are we talking about, it's a connecting factor between unknown rooms and speakers anyone could relate to. Four, it helps you to understand better what you want to hear and if you know where the transition is you can change at will, or example some recordings work better on either side and personal state could want either. If you read Griesinger papers there is a lot of implications with the transition, which you can then utilize as logical tool to help understand what is it that you are hearing. This will tremendously improve listening skill, help you to connect written concepts to your perception of sound in your room. This is very serious stuff in a way, and very little talked about on forums or in general it seems. Saw a chance here to post about it so I took it

The parts in The Griesinger lecture video where he plays the various combinations of reflected and direct sound was very instructional. I think he used the term “muddy” at one point. That’s the one thing I’m still struggling with—why am I still getting excellent detail and timbre with the Omnis (equal to monopoles I compared) when you get the Omni location just right into their own “sweet spot”? Muddy it ain’t. Other than a less precise instrument localization than with monopoles, I’m still struggling to find the Omni flaws. The added 3-D, immersion, wide and deep soundstage, or whatever term you choose, more than offsets the “flat” by comparison from monopoles. I’m about half way through this Tidal playlist of reference demo test type tracks, a good one to find flaws:

TIDAL - High Fidelity Music Streaming

TIDAL is the first global music streaming service with high fidelity sound, hi-def video quality, along with expertly curated playlists and original content — making it a trusted source for music and culture.

tidal.com

ps. this is mostly speculation by me based on limited set of circumstances including few stereo systems in few rooms and few friends, also some forum members in their own circumstances. So, I'd be delighted if you posted what's your stereo listening triangle size and your room size? Rough estimates fine. Thanks!

Let me take some measurements before I reply to this part, also including my prior comments on general reflective properties of the room—I think that is relevant here too. That may be a big factor why they seem to perform so well, relatively speaking, compared to more typical room with more reflective drywall walls.

 

[jim1274]

Hi, sorry I just now noticed Duke was already on to it! When you are too far from speakers there is no envelopment as it's only one neural stream, a flat sounding "noise" as brain isn't picking the direct sound out from all sound in the room but handling them to you as one, doesn't think its important but just noise basically. When you get closer to speakers and notice the shift in perception, brain just picked up the direct sound out from the noise as to it's own neural stream, and now you have two neural streams: one your brain makes attention to, the foreground stream, and another as background stream, the envelopment. As the brain now listens to the direct sound you'd hear spatial cues from the recording you are listening to making it appear more wide and deep soundstage for example, while most of the local room sound is held back by your auditory system. Listening further out the brain doesn't hear the cues but localizes the "noise" into your local room, somewhere around the speakers.

Power with this is, that since you know where the transition happens, you can be sure that closer than this you ought to perceive envelopment and the spatial stuff from the recording, and beyond you cannot. Also engagement, and what not. Now it is possible to evaluate quality of the envelopment for example, as you can turn it on/off using the transition, moving a bit further or closer, it's like AB test in a way. You can now listen how wide your speakers need to be at for natural sound stage, too narrow can be too narrow, too wide can be too wide and so on. Take notes, change speaker position and do it again, compare notes to previous positioning. Fun stuff! It is possible to achieve just right "natural" kind of stereo representation: mono recordings can be very mono narrow and precise while your local room can seem almost muted, while big modern production very big and also enveloping and so on. If you listen far away everything would be kind of the same wide but hazy sound, not much spatial cues from the recording itself.

Similarly, if you wanted to listen effect of speakers being closer or further from front wall I think it is not possible to hear the difference if you listen beyond the transition because it's just noise basically, average of all early reflections in the room and it is a hazy blob of sound, direct or any individual reflection is not discernible from it by definition. It could change a bit, but not as much as happens when you just get closer to speakers. Basically, in order to evaluate what difference it makes to have speakers closer or further from a wall, you must know that there is the audible transition and always listen closer than that so that you are actually able to hear effects on direct sound, or effects on envelopment. If you listen further away, or do not know which side the transition you are listening at, it is not possible to draw conclusions about what you hear, it's just average sound, all reflections combined, you can't be quite sure what you are listening at and perhaps not hear a change as it's just averaged out. It is also easy to draw wrong conclusion.

Anyway, it is easy to have a speaker setup where the sound is hazy, so that listening position is beyond the transition, and there is nothing wrong with it, some people find it fine and the sound they are looking for. It's relaxing sound without too much details to it, your brain is not paying attention to it. It is also quite obvious some recordings were mixed this in mind and those can be quite annoying listened close up, with wild panning and stuff like that and can sound fabulous bit further away. As already said it is very advantageous to know the transition and then utilize for your benefit, listen either side as you feel like.

My text is a bit over emphasized to make good effect on reader. I hope everyone tried listening the stuff with their own setups, read some Griesinger papers and make their own conclusions about things. If anyone finds this interesting, or just crap then please comment, hopefully there will be discussion about the stuff. I think this is core to everything, key to be able to develop listening skill and to gravitate toward hifi sound at home, what ever it is to you with what ever room our speakers you have. Not just that but it is also core to discussion about things, a root so to speak, a key to common understanding: if not understood it is not possible to communicate about stereo hifi sound at homes without confusion as any participant could be talking the same thing but from either side of the transition and no-one understood each other and only confusion would ensue.

I had not listened to the Omnis from the opposite side since moving them well into the room and closer to my listening position. Since they were out enough now, I went “behind” them and listened near what was previously the front wall. Now, THAT was an eye opener. Just by chance, a couple orchestral songs had come up on my demo/test list:

“Ride of the Valkyries” (LSO version)
“Theme from Jurassic Park” (John Williams)

Well, the soundstage became even bigger, actually too much. I may need to move some furniture around and experiment with front to back ratio and listening position from speakers within that ratio.

“In The Air Tonight” (Phil Collins) just came up, a good test track for a number of speaker characteristics, and was just stunning on the Omnis now in more optimal position.

 

[tmuikku]

Yeah, few listening experiments like that and you'll have quite many perspectives to sound of your system in your room, which basically is listening skill, and no you are able to gravitate toward what you actually want with the system, nice!

The parts in The Griesinger lecture video where he plays the various combinations of reflected and direct sound was very instructional. I think he used the term “muddy” at one point. That’s the one thing I’m still struggling with—why am I still getting excellent detail and timbre with the Omnis (equal to monopoles I compared) when you get the Omni location just right into their own “sweet spot”? Muddy it ain’t. Other than a less precise instrument localization than with monopoles, I’m still struggling to find the Omni flaws. The added 3-D, immersion, wide and deep soundstage, or whatever term you choose, more than offsets the “flat” by comparison from monopoles. I’m about half way through this Tidal playlist of reference demo test type tracks, a good one to find flaws:

I had not listened to the Omnis from the opposite side since moving them well into the room and closer to my listening position. Since they were out enough now, I went “behind” them and listened near what was previously the front wall. Now, THAT was an eye opener. Just by chance, a couple orchestral songs had come up on my demo/test list:

One more post, I'll help you thinking with it. Hopefully clears any confusion if there is one. I'm not trying to say omnis, or any speakers for that matter are good or bad, and there is also a lot of assumptions in my posts, which you can confirm for yourself.

Alright, based on your posts I'm assuming you like the close sound where you hear detail and envelopment, and not much the far sound the one you hear in your kitchen.
I'm assuming this, because it is not clear what people like as almost nobody talks about this stuff, and in fact looking pictures and posts by people many seem to like the far sound. Also on local hifi show I went to pretty much all listening seats were beyond the transition... Perhaps they want your brain pay attention to the flashy golden lining and pricetags rather than sound?

Ok, assuming it's the close sound that you want. Also, assuming the audible transition between close and far sound is due to hearing system as Griesinger explains, and that good sound is when the foreground stream is separated by the auditory system, when brain actually pays attention. This is something you would personally always want no matter which room, or which speakers. At least this is something I would want no matter which room and speakers, I'd want this in live music venue and talking with my family members, taking a lecture, and so on, I'd want my brain pay attention to what is important. So, first step with any room and any speakers should be to find the transition, take note how far from speakers you can be, or in other words how big of a stereo listening triangle you can setup with the given circumstances.

Now that you roughly have your listening triangle size you can now setup your setup anywhere in the room to affect envelopment (and perhaps the transition distance), and adjust distance between speakers to make natural sound stage width, what ever feels natural to you, just maintain your distance from speaker in order to stay within the transition. Having speakers 90deg out, side of your head, is sure way to make too big image But, having heard that you can now comfortably play with how far the speakers are apart and find a setup where the image is natural to you, just how you like it. I'm having speakers perhaps 40deg out from median plane for what makes natural big image with my setup for me, so it's bit wider than equilateral listening triangle.

Now that you've found out proportions of your listening triangle by listening the direct sound, you could still try and enhance the envelopment by moving the whole setup within your room, maintaining the current proportions. You'd likely want envelopment as loud as possible, but not too loud in order to be inside the transition. I don't know what goes into the transition, but everything must be contained with the listening triangle size and likely has to do with delays and level of various if not all early reflections. Basically, one would want to delay and perhaps attenuate earliest reflections in order to balance the room sound from early and frontal to later and more surrounding, enveloping. Also the listening position should be as far as possible, but not too far in order to be within the transition, to have lowest possible D/R ratio. Also consider how low end works, due to room modes an also their great contribution to envelopment.

Directional speakers add another dimension to this adjustability, which includes "quality" of the DI and also edge diffraction, some trendy topics. When DI is smooth one can tailor the toe-in just for the envelopment, reduce sound toward "bad" early reflections, without ruining balance of direct sound. If there was only one good listening angle, as with most fullrange driver speakers for example, or with bad edge diffraction, then the toe-in must be set for good direct sound, listening distance is now locked in, and the envelopment ends up being what it is. Whether any of this matters depends only on your listening skill, knowing what is it that you like and how far you are from it and whether you can get there and how.

The above is practical intuition and auditory system based method for positioning speakers that works for me at least. I think this is nice way to find good sound as it is logic applied to perception and ought to work with most rooms and speakers and most importantly doesn't get into technical details like calculating exact milliseconds and azimuths of reflections, IACC and what not, which are relatively hard or impossible to listen to on their own. Such details you should be able to find from literature if you wanted but concentrating on details like this, in my opinion, can prevent you finding good listening setup as at least I would be constantly questioning what I hear, how should this IACC sound like, what I'm supposed to be listening to, what I'm actually hearing? I'd say better results ensue finding positioning based on hearing system using listening skill, and then perhaps look into details to further refine and experiment around.

ps.
for completeness some more thoughts. I'll think that any reasonable room and any reasonable speakers and any average hearing system should have the transition audible. It might be possible that a poor speaker loses original harmonics so bad, that it's not possible to hear it. Room acoustics would affect be it closer or further, really bad acoustics and it could be really close, perhaps non existent as well. Also, it might be not all people can hear it, either by listening skill not detecting before some practice, or perhaps there can be some physical differences although small sample of my friends and relatives all have noticed it pretty much the same as me after talking about it. When one has different room and different speakers, the distance where the transition happens would likely change but this shouldn't matter if you can listen to the transition you could always find where it happens and set your listening spot where you want in relation to the transition. Speakers and room acoustics would affect if and how the direct sound and envelopment can be adjusted further, and your listening skill of course, with prerequisite one is listening within the transition.

If one likes only the far sound, then all above is not very important, just setup the way you like it, splash the walls with sound for maximal bigness

Point with this post is, that in a practical situation like I have, speakers in a family living room, the main issue with the system boils down to how to get the transition distance extend all the way to sofa? Problem is that speaker and sofa position is dictated in which case either acoustics and/or speakers need to be so that the transition extends all the way to the listening position, if that is what is wanted. In my case an omni speaker possibly was not a good choice but something with higher DI. Secondary problem is then to make sure the speaker DI is good so that toe-in can be utilized to tailor some of the envelopment, which likely stays quite poor but as good as it gets. At least there now is some, right perhaps it could be better with omnis or dipoles, but since it is impossible in the particular reality then this is best one can do. Perhaps additional speakers could add envelopment.

Anyway, hopefully this post helps you and anyone else to think about the stuff, try and experiment listening their systems and reason about how to adjust positioning for their liking given the circumstances. It is likely I'm overlooking something and perhaps generalizing too much so if there is some thoughts please share. Have fun!

 

[jim1274]

Lots to chew on with last few replies (plus still absorbing everything that came before).

I’ll describe the “final” positioning shortly, at least “final” as in some fine tuning left yet. Before that, I had already mentioned the change in sound as I leaned forward to get up, shortening the listener to speaker distance. Well, the listening position height as in vertical distance to the ears also impacted sound more than realized. I noticed laying on the couch partially upright , lowering the ear position about a foot or so, changed the sound quite a bit. I was listening and thought “this doesn’t sound right—am I off that much from final speaker position last night?” Just a foot or so higher listener position changed the character (in a good way).

So here is where I ended up in search for best speaker placement:

The room is 15.5’ wide by 25’ long.

Both speakers are 56” from side walls, 72” from front wall, and 102” from listening position. That leaves 74” between the speakers, so not quite an equilateral triangle of speakers and listeners. (I used centerline of the speakers for all measurements)

 

[jim1274]

Lots to chew on with last few replies (plus still absorbing everything that came before).

I’ll describe the “final” positioning shortly, at least “final” as in some fine tuning left yet. Before that, I had already mentioned the change in sound as I leaned forward to get up, shortening the listener to speaker distance. Well, the listening position height as in vertical distance to the ears also impacted sound more than realized. I noticed laying on the couch partially upright , lowering the ear position about a foot or so, changed the sound quite a bit. I was listening and thought “this doesn’t sound right—am I off that much from final speaker position last night?” Just a foot or so higher listener position changed the character (in a good way).

So here is where I ended up in search for best speaker placement:

The room is 15.5’ wide by 25’ long.

Both speakers are 56” from side walls, 72” from front wall, and 102” from listening position. That leaves 74” between the speakers, so not quite an equilateral triangle of speakers and listeners. (I used centerline of the speakers for all measurements)

A couple more thoughts:

The Enterprises seem to be more tolerant of too high a listening position (ears) than too low—less “sonic penalty” above then below optimal height.

Also, the 6’ distance to front wall was to the highly reflective TV screen. The rest of that 6’ plane is well broken up reflections, and the actual physical front wall is almost 2’ further back than the front plane of the TV screen, so maybe the “effective” distance to front wall is more like 7’?

Lastly, here is the general reflective characteristics of the room as mentioned much earlier in the thread:

“I wonder if my living room acoustics are particularly well suited for Omni? It’s not overly damped, but probably better than 99% of living rooms at breaking up reflections. I could go into detail, but wood (redwood) paneling walls are less reflective than drywall, my sloped ceiling is redwood 2 bys on edge, so a groove every 1.5”, large windows across the whole left wall but wood blinds to break that up, huge limestone fireplace on the right wall that is very non-reflective, the front wall filled with AVR rack, a big bookshelf type TV stand with built in center speaker, SVS cylinder sub with fuzzy cover—only reflective surface is my TV.”

 

[jim1274]

I just happened to see a mention in https://www.audiosciencereview.com/...h-active-bass-help-needed.51120/#post-1840564
The user has some freedom in choosing the rear sound - either all or half))
Of course all deftechs are bipolar, not true omni.

The Definitive Technology 9020BP you linked arrived, so the bipolar comparison to Omnis in my room is coming soon. I saw a mention of Axiom “Omnis” (bipolar) over in the other “best design” Omni thread, but also over 10 times the price, so Def Techs are much cheaper “lab supplies” to get a general idea of the design.

 

[jim1274]

The Definitive Technology 9020BP you linked arrived, so the bipolar comparison to Omnis in my room is coming soon. I saw a mention of Axiom “Omnis” (bipolar) over in the other “best design” Omni thread, but also over 10 times the price, so Def Techs are much cheaper “lab supplies” to get a general idea of the design.

I did a brief test of the Def Tech bipolars—initial very prelim report:

Started out 3.5’ from side walls and 4’ from front wall; there was definitely an increase in soundstage depth and “immersion” compared to front firing unipoles, but not even approaching the Omnis. Also, the effect was lost as one moved away from the sweet spot, and almost gone when I moved too far off axis.

When I moved them closer to the listening position and 6’ from the front wall, much of the soundstage collapsed and sounded closer to a conventional box speaker.

I need to do more testing, but don’t think these like being too far into the room. Maybe try even closer to the front wall and also angled to corner to get some side reflection. These seem like they might work better in a much wider room.

The speakers seemed well made and packaged at their price point. Don’t want to comment yet on other sonic quality and attributes, but at $500/pair I’m not sorry I bought them. At the original $629 each price I saw elsewhere, $1258/pair would be another story.

 

[Sir Sanders Zingmore]

the owner I spent time with had been retailing washing machines, he had no knowledge of hi-fi ( or consumer electronics ) whatsoever .

You say that like it's a bad thing

 

[Duke]

I did a brief test of the Def Tech bipolars—initial very prelim report:

Started out 3.5’ from side walls and 4’ from front wall; there was definitely an increase in soundstage depth and “immersion” compared to front firing unipoles, but not even approaching the Omnis. Also, the effect was lost as one moved away from the sweet spot, and almost gone when I moved too far off axis.

When I moved them closer to the listening position and 6’ from the front wall, much of the soundstage collapsed and sounded closer to a conventional box speaker.

What is your impression of the sound quality (rather than the spatial quality) of the Def Techs? Imo the wider the pattern the more important something approaching "constant directivity" becomes from the standpoint of timbre, because in general as the direct-to-reflected sound ratio goes down, the influence of the reflections on perceived timbre goes up.

 

[jim1274]

What is your impression of the sound quality (rather than the spatial quality) of the Def Techs? Imo the wider the pattern the more important something approaching "constant directivity" becomes from the standpoint of timbre, because in general as the direct-to-reflected sound ratio goes down, the influence of the reflections on perceived timbre goes up.

I was planning to comment on that, but wanted a longer listening session first. I do not know if there is any scientific basis to speaker driver “break-in”, but they do seem just a bit better sounding today after maybe 12 hours of use, some at some pretty good SPLs.

My VERY prelim early observation reaction is the Def Techs trailed the Enterprise on almost every front except low frequency extension and output (8” powered sub vs 6” woofer/tweeter, so expected), inferior in things like timbre and low level detail resolution, I’m guessing the opposite of what you expected to hear. These are pretty modest bipolar towers, with only a single midrange rear firing driver—the up-models in the series all add at least a rear tweeter too. Given the low price point, they can hardly use premium drivers—5 total drivers and a built in sub amp must have trade-offs at the price point. The main sonic flaw in these Def Techs is too hot a high end with too bright a sound, shrill at times. It was only bad on some songs with a lot of high end energy. That may be something that EQ would clean up, but never experienced that with the Enterprise Omnis or particularly noted it on the other unipolar speakers I rotated in earlier for a short comparison. Maybe just the crossover design and tweeter used?

I’ve just been playing off a playlist (put together a while back) of prospects to add to my “jukebox” rotation, a wide variety of types since my tastes are pretty wide ranging. A few songs that came up caught my attention as sounding more spacious, but the speakers never disappeared like the onmis did. For lack of a better description, the soundstage became sort of a “triangular” effect at times, with a big deep center image flanked by instruments coming from the front speakers position. That may not make sense—hard to describe. I noticed it particularly on two live songs “Shaft” and “Use Me” from Isaac Hayes Live at the Sahara Tahoe then again on “Belle Isle Daze” from The Lyman Woodward Organization - Saturday Night Special album. At times these bipolars give the Omni a decent run for the “soundstage” money, getting close at times. The one huge advantage of the Omnis is the wide listening area where they sound almost as good as the sweet spot, something the bipolars are crushed on.



Like I’ve said all along, I’m still trying to figure out what I’m losing to get that big immersive sound of Omnis. These Def Techs are not going to achieve that, but this was more to compare the soundstage aspects of Omni vs bipoles. I will say that while flawed, for $500 these Def Techs are a lot of speaker for the money and very listenable. Since the Enterprise is a circa $3500 speaker, it’s hardly a fair fight. Something like the Axiom bipolars ive seen mentioned on the forum might be a whole different story, but those also are quite a bit more than these Duevels. I could easily live with a good bipole, capturing some of the magic of an Omni and maybe besting it in some areas with a higher quality bipolar tower design. The soundstage gap to an Omni is less than how much it outdistances a monopole—did that make sense?

Got a little long-winded and rambling…sorry…the thoughts and impressions are just forming, so kinda thinking out loud here.

 

[jim1274]

Before giving a quick update of the Omni journey, thanks much again for everyone who has generously responded to my posts. I’ve learned a lot more than just about Omnis here, of benefit to using other speaker types and placement strategies, developing critical listening skill along the way (and really making me think hard about what constitutes “good sound”). Anyway..

Late last night, I replaced the Def Tech bipoles (used to compare against the Duevel Omnis) with a pair of dipoles I own, primarily to compare the soundstage vs the Omnis, but getting more in the process. The speakers are Heil ESS AMT 1b, a dipole with wide horizontal dispersion front and back from the 700hz crossover point and up. They worked better than the Def Tech bipoles in all aspects of the soundstage, giving a wider and deeper soundstage, better instrument localization, disappearing, and much better performance off axis from the sweet spot. While not qiite the immersion and huge soundstage of the Omnis, enough to satisfy. The “more” part was the AMT amazing resolution, detail, and clarity. The Duevels didn’t seem lacking in that area, but these were on another level it seemed. I’m going to do a direct A/B to compare that characteristic. These AMTs are flawed speakers in some ways, but made me think another speaker that provides a good part of the Omni soundstage aspect but improves on the other sound characteristics, may be better overall. Specifically, I’m thinking the Soundlabs may fit the bill, not that there aren’t potentially other dipole options that might do the trick.

 

[jim1274]

As you persist with omni speakers, the phenomenon of personal adaptation will take hold, and you will care less and less about their shortcomings. But they are, indeed, a lower-tier solution for sound reproduction generally, while still capable of being very satisfying. The “omnidirectional loudspeakers = best design available” thread starts with a post full of classic omni fan misconceptions and misdirections. Over hundreds of posts and much disputation, a more balanced view emerges of their real place in the audio pantheon.

cheers

I’ve been revisiting the earlier posts now that I’ve had more listening and comparisons to a bipolar type and just recently the dipoles with the AMT tweeter, both affording some of the soundstage enhancements of the Omni.

Your older post here hit home, both the “adaptation” phenomenon as well as the compromises that the AMT tweeter exposed with its fine detail resolving capability (yet to be directly compared—the onmis were pretty good on that). If these AMTs didn’t have other sonic flaws, good chance these would provide enough in the soundstage aspect to be preferable to the Omnis. I’m still not ready to abandon the soundstage enhancements of other speaker types compared to the strengths of forward firing speakers.

 

[MattHooper]

I’ve been revisiting the earlier posts now that I’ve had more listening and comparisons to a bipolar type and just recently the dipoles with the AMT tweeter, both affording some of the soundstage enhancements of the Omni.

Your older post here hit home, both the “adaptation” phenomenon as well as the compromises that the AMT tweeter exposed with its fine detail resolving capability (yet to be directly compared—the onmis were pretty good on that). If these AMTs didn’t have other sonic flaws, good chance these would provide enough in the soundstage aspect to be preferable to the Omnis. I’m still not ready to abandon the soundstage enhancements of other speaker types compared to the strengths of forward firing speakers.

I enjoyed my omnis for at least ten years. A pretty good run in my book!

 

[MattHooper]

Something to remember when reading the more negative-omni posts, in which people will quote an off-handed Toole remark like "they are effects generators."

First: while some generalizations are available, not all rooms are the same, so the amount, type and character of the reflections will vary in terms of emphasis and sonic character.

I had MBL omnis in a room which has quite a bit of acoustic treatment and reflectivity control. I could make it relatively "dead" or "alive" and anything in between. Contrary to those who tend not to speak from actual experience owning such speakers, they were not throwing vague imaging or artificially enlarging the soundstages. The soundstages would shape shift just as with any of my direct radiating speakers, and the imaging was similarly focused. As with my front firing box speakers, I could add or subtract wall reflections to alter the effect.

What people also tend to miss, when dissing omnis as lower tier options, is that it's not JUST that they can please with specious reflections. Remember that Toole has pointed out how we don't like resonances. These can come from drivers, or speaker cabinets etc. But Toole points out that when the sound seems to glom in to a speaker, seems coming from or stuck in the speaker, this is often due to a resonance cuing our ears. When resonances are sufficiently removed or controlled, the effect is that the sound no longer seems "stuck" in the speaker and floats more free of the speaker. The best speakers, in this regard, can have this character of the sound detached from the speaker even in hard panned instruments or even in mono speakers, the sound seems to "float" free of the speaker rather than sound stuck in the speaker. And this is a sign of a good design, and something we find pleasing.

Well...omnis like the MBLs do just this, almost by nature. There's no box (at least with mine in the critical midrange) to resonate. Even in mono, a hard panned sound easily floats free from the structure of the speaker. They eat many speakers for lunch in this regard. So it's not JUST a party trick of spraying sound around the room (you don't HAVE to exaccerbate those reflections if you don't want to), but they also are very good at fulfilling one of the functions of a well designed speaker in terms of "disappearing" as a sound source and not giving a "speakerly' coloration to the sound.

So in a well damped room the effect I was getting from the MBLs was both very well focused imaging, soundstaging that was similar to my box speakers and which changed with each recording, but also a particularly "box free sound" which helped reduce the mechanical nature of the playback and often sounded more "natural" to my ears. I would compare my box speakers with the omnis, against my wife's speaking voice in the room, and it was the omnis that captured the essence of a "voice in free space" the best, IMO.

 

[jim1274]

Something to remember when reading the more negative-omni posts, in which people will quote an off-handed Toole remark like "they are effects generators."

First: while some generalizations are available, not all rooms are the same, so the amount, type and character of the reflections will vary in terms of emphasis and sonic character.

I mentioned earlier that my room acoustics may be well suited to Omnis in being a much less reflective room than most, maybe getting much better results than others have had in their rooms

I had MBL omnis in a room which has quite a bit of acoustic treatment and reflectivity control. I could make it relatively "dead" or "alive" and anything in between. Contrary to those who tend not to speak from actual experience owning such speakers, they were not throwing vague imaging or artificially enlarging the soundstages. The soundstages would shape shift just as with any of my direct radiating speakers, and the imaging was similarly focused. As with my front firing box speakers, I could add or subtract wall reflections to alter the effect.

What people also tend to miss, when dissing omnis as lower tier options, is that it's not JUST that they can please with specious reflections. Remember that Toole has pointed out how we don't like resonances. These can come from drivers, or speaker cabinets etc. But Toole points out that when the sound seems to glom in to a speaker, seems coming from or stuck in the speaker, this is often due to a resonance cuing our ears. When resonances are sufficiently removed or controlled, the effect is that the sound no longer seems "stuck" in the speaker and floats more free of the speaker. The best speakers, in this regard, can have this character of the sound detached from the speaker even in hard panned instruments or even in mono speakers, the sound seems to "float" free of the speaker rather than sound stuck in the speaker. And this is a sign of a good design, and something we find pleasing.

Well...omnis like the MBLs do just this, almost by nature. There's no box (at least with mine in the critical midrange) to resonate. Even in mono, a hard panned sound easily floats free from the structure of the speaker. They eat many speakers for lunch in this regard. So it's not JUST a party trick of spraying sound around the room (you don't HAVE to exaccerbate those reflections if you don't want to), but they also are very good at fulfilling one of the functions of a well designed speaker in terms of "disappearing" as a sound source and not giving a "speakerly' coloration to the sound.

So in a well damped room the effect I was getting from the MBLs was both very well focused imaging, soundstaging that was similar to my box speakers and which changed with each recording, but also a particularly "box free sound" which helped reduce the mechanical nature of the playback and often sounded more "natural" to my ears. I would compare my box speakers with the omnis, against my wife's speaking voice in the room, and it was the omnis that captured the essence of a "voice in free space" the best, IMO.

My next step is to do a proper instantaneously switching A/B of the Omnis compared to the other “box” speakers, dipoles, and such on hand. This evening when I moved the AMT dipoles out and the Omnis back in, I immediately preferred the more pronounced immersive soundfield of the Omnis. I had flagged a few songs to compare the detail resolving, a strong suit of the AMT, expecting the Omni to lag a bit, but did not find that to be the case. I need to get this A/B going to really compare the various sonic characteristics directly in real time.

I’m still not yet finding what the Omnis “leave on the table” vs all the other speakers I’ve moved in and out.

 

[tmuikku]

It's gonna be a tough test! They all cannot be located at same physical location so I think it's better put them to ideal positions in room what ever those are for each, while keeping listening position static. Hopefully they do not interfere with each other too much, meaning that sound of a speaker is not affected too much by another speaker in close proximity, as it would diffract and reflect sound. Then their frequency response and power response varies so not sure how you could isolate these effects in order to compare just the "ideal radiation pattern", which I've understood is your current quest. I mean, you could have two different omni speakers and prefer the other one over the other, perhaps two pairs of same speaker would differ because they cannot colocate.

It's a tough mental task to try and ignore frequency response issues, resonances and all little things that differ between the speakers, in order to concentrate on directivity and effects of room in order to be able to generalize which is better type of speaker. For example bandwidth of all speakers could be shrunk to the worst one, perhaps try do something to frequency responses if wildly different, but this is not possible due to very much varying directivities so it'll heavily affect impression. At least you should level match them if nothing else, louder ranks better.

Anyway, I think you might be able to compare the speakers in a way that makes sense to you and get some results that make sense to you, pick the best pair from those you have there that you like most, for what ever combination of reasons you like them most. I'm afraid it is not just due to radiation pattern, but combination of multiple things. Anyway, comparison between various radiation patterns could be done in virtual reality, where most of these issues can be eliminated and situation simplified with ideal sound sources that can be A/B tested with click of a button, something that is not possible in reality. I've got impression that this is not possible yet though, perhaps in near future. Recently tried treble.tech app as it is low entry, but auralization seems to be compromized to enable realtime AR or something, it's not accurate enough to do this kind of comparisons at this point in time.

 

[jim1274]

It's gonna be a tough test! They all cannot be located at same physical location so I think it's better put them to ideal positions in room what ever those are for each, while keeping listening position static. Hopefully they do not interfere with each other too much, meaning that sound of a speaker is not affected too much by another speaker in close proximity, as it would diffract and reflect sound. Then their frequency response and power response varies so not sure how you could isolate these effects in order to compare just the "ideal radiation pattern", which I've understood is your current quest. I mean, you could have two different omni speakers and prefer the other one over the other, perhaps two pairs of same speaker would differ because they cannot colocate.

Yeah, I’ve thought of that. I think it will be good enough to get a general idea. I’ve been having a similar discussion on the “dipole vs box speakers” thread,

Blumlein88 made a good point there recently that you mention later in your post here:

“Really you need to EQ to at least similar response. You cannot do much about off axis, but direct sound you can get close. Otherwise everything is murky due to the FR differences. FR is the most obvious thing we hear.”

That’s gonna be tough to do, but am mulling over a scheme that might work using 2 Roon zones and EQ capability.

It's a tough mental task to try and ignore frequency response issues, resonances and all little things that differ between the speakers, in order to concentrate on directivity and effects of room in order to be able to generalize which is better type of speaker. For example bandwidth of all speakers could be shrunk to the worst one, perhaps try do something to frequency responses if wildly different, but this is not possible due to very much varying directivities so it'll heavily affect impression. At least you should level match them if nothing else, louder ranks better.

Anyway, I think you might be able to compare the speakers in a way that makes sense to you and get some results that make sense to you, pick the best pair from those you have there that you like most, for what ever combination of reasons you like them most. I'm afraid it is not just due to radiation pattern, but combination of multiple things. Anyway, comparison between various radiation patterns could be done in virtual reality, where most of these issues can be eliminated and situation simplified with ideal sound sources that can be A/B tested with click of a button, something that is not possible in reality. I've got impression that this is not possible yet though, perhaps in near future. Recently tried treble.tech app as it is low entry, but auralization seems to be compromized to enable realtime AR or something, it's not accurate enough to do this kind of comparisons at this point in time.

I’m thinking maybe it can be done using my AV receiver, using digital outs of 2 Roon endpoint devices to 2 seperate digital inputs on the AVR, then EQ and level match each zone in Roon, just switching between digital input source inputs on the AVR. That way the DAC and amp would be consistent and not a variable. This is getting complicated…

I hope that made sense….