Sound quality: Vertical directivity vs speaker radiation width

[hvbias]

Strictly between these two choices - vertical directivity or speaker radiation width (horizontal), what do you think matters more for sound quality?

I've now auditioned nearly all the speakers I was interested in though they keep coming out with superb measuring speakers at a rapid rate. But the ones that I have been thinking about for a while have all been heard.

I am not going to name speakers and have removed the names from Erin's measurements. If others want to that's fine.

And I do not mean poor vertical directivity that is all over the place, I mean excellent vertical directivity except for the narrowing that occurs at the woofer/mid to waveguide tweeter transition point. Also does not mean a flawless vertical directivity speaker gets a pass with a really messy horizontal directivity, it too would have excellent horizontal directivity. Basically all the speakers I heard were excellent measurement wise in one way or another but sacrificed something in either of these two areas.

My opinion after hearing all of these, and I find my preference aligning with Erin is that I like a medium/medium-high horizontal radiation pattern. I never noticed the narrowing vertical directivity at the transition point of the two drivers unless I was standing with knees slightly bent at a very narrow window. Sitting or standing no issue. These medium to medium-high horizontal coverage speakers always sounded the best to me with symphony, concerto, solo piano, and chamber music. The ones that gave the most even horizontal, depth, and width soundstage that differed recording to recording. The narrower directivity speakers sounded more like speakers. I don't really want to get into audiophile terms so "sounded like speakers" is about the best I'm going to say, basically more obvious where the sound was coming from.

My preference for radiation:

 

[fpitas]

FWIW, my very picky friend wanted to poke holes in my MTM scheme, but ended up liking the narrow vertical directivity.

 

[hvbias]

FWIW, my very picky friend wanted to poke holes in my MTM scheme, but ended up liking the narrow vertical directivity.

But they would have narrowing at each driver transition? The only flawlessly measuring vertical directivity speakers I've seen are coaxials. These are the speakers I mean when I say flawless vertical directivity.

 

[fpitas]

But they would have narrowing at each driver transition? The only flawlessly measuring vertical directivity speakers I've seen are coaxials. These are the speakers I mean when I say flawless vertical directivity.

The vertical narrowing starts at about 300Hz, narrowing to 40 degrees beamwidth by 800Hz, then steady out to maybe 8kHz. I'm not sure how coaxials compare; why would they narrow in the vertical direction only?

 

[hvbias]

The vertical narrowing starts at about 300Hz, narrowing to 40 degrees beamwidth by 800Hz, then steady out to maybe 8kHz. I'm not sure how coaxials compare; why would they narrow in the vertical direction only?

They don't, they are completely even in the horizontal and vertical.

 

[fpitas]

They don't, they are completely even in the horizontal and vertical.

OK, gotcha.

 

[mj30250]

Horizontal radiation matters more because our ears are arrayed horizontally.

 

[fpitas]

Horizontal radiation matters more because our ears are arrayed horizontally.

That may be a major factor.

 

[Sebba]

Horizontal radiation matters more because our ears are arrayed horizontally.

I agree. So Dr. Toole in one of his interview.

 

[dualazmak]

Horizontal radiation matters more because our ears are arrayed horizontally.

I essentially agree.

Although quite belated, I just came to this interesting thread.

BTW, in the course of my DSP-based multichannel multi-SP-driver multi-amplifier fully active stereo audio project, I experienced and implemented rather unique physical alignment/positioning of my metal-horn super-tweeters which sing together with my Be-dome-tweeters; the results and implementation is somewhat related to the discussion here on this thread, I assume.

If you would be interested please visit my post here on my project thread. I experimented various physical positions of super-tweeter "around" my main SP cabinet as shown in the photo below. At least in my setup and room acoustics, I found it would be the best having my super-tweeters in very unique physical positioning/alignment (position #5 in the below photo) for which I have briefly discussed in terms of, a kind of, "quasi-vertical (or pseudo-vertical?) sound staging/imaging";

In the position #5, WO (woofer) and SQ (midrange-squawker) are "sandwiched" by TW (tweeter) and ST (super-tweeter), and the high-Fq sound is coming not from point sources but (as if) coming from a big face/surface covering all the "NS-1000+outer round space", I feel.

For your reference, Be-TW covers ca. 6 kHz - 15 kHz, and the highly efficient metal-horn-ST covers ca. 8.8 kHz - 22 kHz in about 10 dB lower gain than TW; super-tweeter ST,therefore, acts as supplement/support in 7 kHz - 14 kHz for Be-TW, and it also compensates slight decline of Be-TW in 14 kHz to 22 kHz (ref. here).

I wrote there;
>Our ears are located left and right of our head, and hence we are rather sensitive for left-right sound image/allocation. On the other hand, our ears and brain would be relatively gullible with up-and-down sound staging, I assume. I think that my unique physical alignment (positioning) of super-tweeters at under the main SPs, together with the upper tweeters, would give pseud-coaxial sound staging if complete time alignment has been achieved like in my setup (please refer to my summary post here), where tweeter and super-tweeter sing together higher than about 8 kHz.
>
>In any way, I would like to suggest those who using super-tweeters to at least try/test the positioning so that super-tweeter and tweeter would sandwich the woofer and squawker from up and down.

For your reference, you can find the latest system setup information as of August 3 2023 here post #774 on my project thread.

 

[eboleyn]

Horizontal radiation matters more because our ears are arrayed horizontally.

I think it has far more to do with the fact that if you look at a typical room, the positions of our ears tend to stay in a space that is restricted vertically but pretty open horizontally throughout the room. Our ears may be arrayed horizontally also because our physical world tends to be the ground and a large horizontal plane around us. We essentially live in a 2D plane with a bit of height.

 

[hvbias]

The main sticking point about directivity has been having a timbrally similar reflection off the front/back/side walls as the direct sound from the speakers. So by saying vertical directivity is not that important are we discounting the importance of floor and ceiling reflections?

How our ears are arranged is IMO a strange thing to mention.

 

[eboleyn]

The main sticking point about directivity has been having a timbrally similar reflection off the front/back/side walls as the direct sound from the speakers. So by saying vertical directivity is not that important are we discounting the importance of floor and ceiling reflections?

How our ears are arranged is IMO a strange thing to mention.

Huh, it doesn't seem strange to me, the arrangement of our ears and our semi-horizontal planar/ground existence seems pretty solidly linked to me... and similarly linked to why we have speakers primarily arrayed in horizontal patterns (such as a "front speaker pair"), with vertical locations being typically a secondary consideration in all but the more fancy setups.

As to vertical vs. horizontal directivity of speakers and reflections thereof... I wouldn't say vertical directivity doesn't matter at all, but it's clear that horizontal directivity is more important. Common speaker designs bear this out, with obvious different design structure for say front/bookshelf speakers to get good and symmetric/non-lobed horizontal spread when aligned standing up, vs say "center" speaker designs which are optimized for good and symmetric/non-lobed horizontal spread when aligned laying down.

The vertical directivity of speaker designs vary widely, and have often have lobing issues where some frequencies cancel out as you go off the front axis vertically, which can be considered an acceptable design point.

 

[hvbias]

Huh, it doesn't seem strange to me, the arrangement of our ears and our semi-horizontal planar/ground existence seems pretty solidly linked to me... and similarly linked to why we have speakers primarily arrayed in horizontal patterns (such as a "front speaker pair"), with vertical locations being typically a secondary consideration in all but the more fancy setups.

As to vertical vs. horizontal directivity of speakers and reflections thereof... I wouldn't say vertical directivity doesn't matter at all, but it's clear that horizontal directivity is more important. Common speaker designs bear this out, with obvious different design structure for say front/bookshelf speakers to get good and symmetric/non-lobed horizontal spread when aligned standing up, vs say "center" speaker designs which are optimized for good and symmetric/non-lobed horizontal spread when aligned laying down.

We are easily able to localize sounds coming from above us like hearing a plane or helicopter overhead. Or standing on the ground floor outside and hearing someone speaking from floors above us. Likewise being able to localize toddlers from the floor just from audio cues.

The vertical directivity of speaker designs vary widely, and have often have lobing issues where some frequencies cancel out as you go off the front axis vertically, which can be considered an acceptable design point.

Should it be acceptable? This is far more important than some of the measurement parameters of electronics people hand wring over that are entirely inaudible.

 

[eboleyn]

We are easily able to localize sounds coming from above us like hearing a plane or helicopter overhead. Or standing on the ground floor outside and hearing someone speaking from floors above us. Likewise being able to localize toddlers from the floor just from audio cues.

Sure, I wasn't trying to say that we only have horizontal localization capability, just that it's notably better in that axis on average.

Should it be acceptable? This is far more important than some of the measurement parameters of electronics people hand wring over that are entirely inaudible.

Hmm, fair criticism... perhaps it should have said "...which have often been considered an acceptable...". I personally do care about vertical directivity (and like to restrict it so floor/ceiling effects are minimized), but the very fact that so many speakers don't control for it that well and in so many different ways, but nearly universally have much tighter control for horizontal directivity just supports that it's a secondary effect.

 

[hvbias]

Hmm, fair criticism... perhaps it should have said "...which have often been considered an acceptable...". I personally do care about vertical directivity (and like to restrict it so floor/ceiling effects are minimized), but the very fact that so many speakers don't control for it that well and in so many different ways, but nearly universally have much tighter control for horizontal directivity just supports that it's a secondary effect.

I don't think it's a secondary effect because it's not important, I think it's a secondary effect because manufacturers simply can't do it properly.

Unfortunately we don't have blind tests for speakers that have exceptional horiztonal directivity but poor vertical directivity vs ones that do both exceptionally well. If I had to guess based off how much difference I can hear being in audiophile's rooms after they have added ceiling treatments or wood floors vs wood floors with a thick throw over them I would conclude that it matters very much.

 

[olieb]

Horizontal radiation matters more because our ears are arrayed horizontally.

Probably it is the other way around.
Our ears are arrayed horizontally because sound information in the horizontal plane is more relevant most of the time. And two ears at the sides of the head can do that better.

 

[Blockader]

Strictly between these two choices - vertical directivity or speaker radiation width (horizontal), what do you think matters more for sound quality?

I've now auditioned nearly all the speakers I was interested in though they keep coming out with superb measuring speakers at a rapid rate. But the ones that I have been thinking about for a while have all been heard.

I am not going to name speakers and have removed the names from Erin's measurements. If others want to that's fine.

And I do not mean poor vertical directivity that is all over the place, I mean excellent vertical directivity except for the narrowing that occurs at the woofer/mid to waveguide tweeter transition point. Also does not mean a flawless vertical directivity speaker gets a pass with a really messy horizontal directivity, it too would have excellent horizontal directivity. Basically all the speakers I heard were excellent measurement wise in one way or another but sacrificed something in either of these two areas.

My opinion after hearing all of these, and I find my preference aligning with Erin is that I like a medium/medium-high horizontal radiation pattern. I never noticed the narrowing vertical directivity at the transition point of the two drivers unless I was standing with knees slightly bent at a very narrow window. Sitting or standing no issue. These medium to medium-high horizontal coverage speakers always sounded the best to me with symphony, concerto, solo piano, and chamber music. The ones that gave the most even horizontal, depth, and width soundstage that differed recording to recording. The narrower directivity speakers sounded more like speakers. I don't really want to get into audiophile terms so "sounded like speakers" is about the best I'm going to say, basically more obvious where the sound was coming from.

My preference for radiation:

There is no strong consensus about the value of the vertical reflections for sound quality. We do not even know whether they are taken into account by human hearing at all.

What we know is that they can destructively interfere with the direct sound. And we do not want that.

 

[Duke]

Strictly between these two choices - vertical directivity or speaker radiation width (horizontal), what do you think matters more for sound quality?

I didn't vote because I wouldn't characterize my preferences in those particular terms.

Imo the off-axis energy (its 3-dimesional pattern, relative loudness, and spectral content) is a means to an end. This desired end presumably includes creating a convincing or at least enjoyable spatial presentation, along with natural or at least enjoyable timbre, and freedom from distracting colorations and/or artifacts.

I'm not convinced that there is a single generally-applicable best way to end up with a reflection field that is spectrally correct, adequately diffuse and arriving from many directions, neither too strong nor too weak, arriving neither too early nor too late, and decaying neither too fast nor too slow. And imo the interaction between the loudspeakers' off-axis response and the room means that the end result is neither entirely up to the speakers nor entirely up to the room.

In the course of product development I've experimented with emphasizing reflections in the horizontal plane; emphasizing reflections in the vertical plane; and distributing the reflections more or less equally in both planes. My preference is for more or less equal distribution of the reflections in both planes.

That being said, in my opinion the reflection arrival times generally matter more than their arrival directions, with later reflection onset generally being preferable to earlier reflection onset.