Is it possible to cover the whole spectrum, high SPL, low distortion with a 2-way?

Generally, as wide as possible, unless you need to restrict it because of room acoustics.

I prefer studio monitor type speakers with 1" waveguide loaded dome tweeters and 5-8" woofers for that kind of distance, my favourite being the old behringer B2031A.

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Yes, I cannot believe I skipped over that Behringer back in the days...I had no idea.

To your point....the jbl 2386, remains 30+/- to 20,000khz at 1 meter......The 2380a is wider yet at 1 meter
The Hvdiff is 30+/- if the listening distance is relaxed to mid or farfield...and a wider polar yet....

I think you are only arguing about things of preference...I have a hypothesis to scratch...Though the sweet spot may be painfully small with a big horn at 1 meter....will the energy within the small beamwidth be an sound engineers heaven? There is evidence that suggest so, in my opinion. I want to investigate that, is all.

Can someone help me make this formula work?
If we use +/-15deg w.r.t axis at 1.5m the soundfield width would be +/-1.5m*tan(15deg)=+/-40cm = 80cm wide at 14.5Khz.
Its one thing talk about beam width....the next level is to decipher the literally size of the window at 1 meter...I cannot get this formula DonK gave me, to work. It is likely a mathematical misunderstanding on my part. Looking at the solved formula for the 1.5m listening distance, at 14.5k, the window is 31inches wide lol...wheres all the beaming at? My heads not 31inches wide lol sounds like you guys are asking for gigantic unnecessarily wide sweet spots.
 
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If i were you, I'd go ahead, get the Axi and whatever horn you think works, and build/try that before proceeding any further with trying to figure out what goes below it.

Will the Axi/horn sound good per your intentions?
Will it sound good as low as you want to go?
Does it have an acceptable VHF response?
Will it sound good as close as you want to listen?
Only one way to find out....
Models don't make sound.....

You may find the Axi simply doesn't work they way you hope...and have to rethink the CD/horn combo.

I think it's a great project idea (other than the listen at 1m aspect),
and truly hope you acquire the Axi/horn and get it running, along with a suitable bottom end.
But imo it's a step at a time project, as you are in uncharted waters.
And the first pragmatic step is currently there to be made...

Oh, i think i know why I and others never gathered you want to listen at 1m....
Your post #5 reads to me, like simply what SPL spec you were looking for...especially since a SPL spec is typically quoted at 1m.
No real way to have gleaned you meant listen at 1m too,..... imho & fwiw..
 
.oh but wait again...sound engineers already know that headphones are more precise than loudspeakers, for the task of judging frequency specific sound pressure level aka EQ....

Who said that? As far as I know, it's very hard to find a sound engineer who prefer headphones over speakers. As long as the room is very quiet and acoustically well controlled, I can't find any advantage with headphones...
 
Who said that? As far as I know, it's very hard to find a sound engineer who prefer headphones over speakers. As long as the room is very quiet and acoustically well controlled, I can't find any advantage with headphones...

No reason to look for some special person to claim it, just make the comparison yourself...as I said, headphones fall short when it comes to bass and high treble. Headphones are used in conjunction with loudspeaker systems, not to replace them, though there are famous sound engineers who work solely with headphones, if only to prove the point that it can be done. Especially with some of the latest software that help bridge the gap between headphones and loudspeakers.

Its also hard to find sound engineers with enough knowledge to build their own systems so thats no really saying much....
 
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No sir, the 15m is the midrange model from Acoustic Elegance! My listening range will be from 1m to 3m. I already know I am breaking the rules by listening at 1m but I am ok with sacrificing coherency for accuracy of spl, in which, dynamic contrast, is the focus of this design. I understand that proper distance is needed for the driver to sound as one, though I forget the technical definition for this aspect, I care not, because, white russian lol!
I am sort of concerned about the AE 15m....I want/need the best midrange available. I have a 4" midrange currently and it is not exactly lacking, do to proper size vs physics so now with a 15"midrange, I need to be more critical in choice of mid range driver. I think you support the 15m and I support you so...I am ok with it, but I have to put it out there in case of doubt.
I sincerely preferred a sealed subwoofer...

19th May 2019
 
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If i were you, I'd go ahead, get the Axi and whatever horn you think works, and build/try that before proceeding any further with trying to figure out what goes below it.

Will the Axi/horn sound good per your intentions?
Will it sound good as low as you want to go?
Does it have an acceptable VHF response?
Will it sound good as close as you want to listen?
Only one way to find out....
Models don't make sound.....

You may find the Axi simply doesn't work they way you hope...and have to rethink the CD/horn combo.

I think it's a great project idea (other than the listen at 1m aspect),
and truly hope you acquire the Axi/horn and get it running, along with a suitable bottom end.
But imo it's a step at a time project, as you are in uncharted waters.
And the first pragmatic step is currently there to be made...

Oh, i think i know why I and others never gathered you want to listen at 1m....
Your post #5 reads to me, like simply what SPL spec you were looking for...especially since a SPL spec is typically quoted at 1m.
No real way to have gleaned you meant listen at 1m too,..... imho & fwiw..

Your point is duly noted...Its still interesting to debate the details in the meantime, I have to spend finding the best price on wood cutting...Covid19 has wood shops either closed or just now reemerging, and now that work is back in season...my one day off (Sunday) combined with random rain days...theres time to pick at details is all.
 
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Generally, as wide as possible, unless you need to restrict it because of room acoustics.

I prefer studio monitor type speakers with 1" waveguide loaded dome tweeters and 5-8" woofers for that kind of distance, my favourite being the old behringer B2031A.

Flat Response -

Techtalk Speaker Building, Audio, Video Discussion Forum


Still exist but active, iirc !


In the shoes of camplo, I wouldn't care about spl at 1 meter and will focus on a very clear sound and good soundstage


this Fujitsu Ten Eclipse TD712z loudspeaker Page 2 | Stereophile.com
with a digital time aligned sub under Helmotz frequency of his room.
dynamic is compressed in most reccording anyway. If you average level is low as a 75 db and if most of people had 115 db peaks able speakers. Most classic speakers don't go that high, it would make sense. But todays, not sure it would (headphones and nomadism + streaming on demand won... imo
 
Still exist but active, iirc !


In the shoes of camplo, I wouldn't care about spl at 1 meter and will focus on a very clear sound and good soundstage


this Fujitsu Ten Eclipse TD712z loudspeaker Page 2 | Stereophile.com
with a digital time aligned sub under Helmotz frequency of his room.
dynamic is compressed in most reccording anyway. If you average level is low as a 75 db and if most of people had 115 db peaks able speakers. Most classic speakers don't go that high, it would make sense. But todays, not sure it would (headphones and nomadism + streaming on demand won... imo

Well the time alignment is apart of the system. When I work on a song, most times, there is no compression there unless I put it there. To be able to judge your decisions related to compression, limiting, and eq...you'd want a system that introduces non of those attributes coincidentally...thus the desire for a high output level potential even though there is no intention of listening at such high levels as well as very smooth, relatively neutral voicing.

I believe that I can achieve this high resolution by decreasing as much as possible the excursion of all drivers...hence the large high efficiency drivers at nearfield.
 
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Can someone help me make this formula work? Its one thing talk about beam width....the next level is to decipher the literally size of the window at 1 meter...I cannot get this formula DonK gave me, to work. It is likely a mathematical misunderstanding on my part. Looking at the solved formula for the 1.5m listening distance, at 14.5k, the window is 31inches wide lol...wheres all the beaming at? My heads not 31inches wide lol sounds like you guys are asking for gigantic unnecessarily wide sweet spots.

It might be something as simple your calculator/spreadsheet is using radians (DRG mode) instead of degrees.

I made a few drawings with measurements to show the speaker beam angle (+/-15deg), the beam width, and the sweet spot width. The speaker axial center is always aimed at the center of the listeners head (circle). Wide enough for a single listener, but maybe not for a group of people.
.
 

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Sorry if I come off aggressive, its a road construction thing...I've been amidst my work family. I really do enjoy you guy's company.
Fair Enough

The problem in my head about the synergy is...what size will this be...what would it look like?.
Most likely something like a K402 or Marks Synergy #7, they work for a driver that can cover a lot of ground on it's own. The size of the woofers to go below it really are what dictate most of the size as well as the pattern control desired. But for nearfield there are better compromises in any case.

Having ~200hz-20.000khz is very Synergy like is it not?
Maybe, getting more of the range covered from a single point is a big part.

Can someone help me make this formula work? Its one thing talk about beam width....the next level is to decipher the literally size of the window at 1 meter...I cannot get this formula DonK gave me, to work. It is likely a mathematical misunderstanding on my part. Looking at the solved formula for the 1.5m listening distance, at 14.5k, the window is 31inches wide lol...wheres all the beaming at? My heads not 31inches wide lol sounds like you guys are asking for gigantic unnecessarily wide sweet spots.

Edit: Don beat me to it. Here you go, google scientific calculator put it in degrees instead of radians then type 1.5 x tan 15 and you will get the answer in metres. There is your 40cm half angle. Change the 1.5 or the 15 to vary the distance and angle.


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OK now we are rolling!!! I just had to change the settings to degrees as suggested... So in the future if we have a discussion about this supposed beaming...I'm bustin out this formula!

By intelligent coincidence, I once said that the polar shouldn't be any smaller than 15 degrees...this turns into 10 inches at 1 meter! Thats perfect as far as I'm concerned...
Unfortunately, Docali isn't willing to make any more horns for me, so I am stuck with the models I have.

The HvDiff is an impressive profile to me... If I could create another one I'd adjust the flare rate to create a horn just as wide but allowing the polar to be 15 degrees at 20khz....

I could scale the horn down and then maybe DonK can apply his roll off technique and walla>?
 
So in the future if we have a discussion about this supposed beaming...I'm bustin out this formula!
You don't seem to be grasping what "beaming" means. You could have a speaker with 90 degree beamwidth at 20KHz that would be beaming if the beamwidth at 2KHz was 180 degrees.

It is the narrowing with increasing frequency that the term refers to. If you want or are happy with a +/-15 degree window great. If it was the same beamwidth down to lower frequencies it would not beam.

The DI shows this the best. This needs some manual intervention to get out of ABEC so it isn't often shown.

The difference between what will be heard on axis and what will be heard or reflected back off axis.
 
You don't seem to be grasping what "beaming" means. You could have a speaker with 90 degree beamwidth at 20KHz that would be beaming if the beamwidth at 2KHz was 180 degrees.

It is the narrowing with increasing frequency that the term refers to. If you want or are happy with a +/-15 degree window great. If it was the same beamwidth down to lower frequencies it would not beam.

The DI shows this the best. This needs some manual intervention to get out of ABEC so it isn't often shown.

The difference between what will be heard on axis and what will be heard or reflected back off axis.

Ok I see, its been explained before but for some reason I keep focusing on the window size....

I would think that in particular, near field would be least affected by the negatives of not having constant directivity, so +1 for near field again for being the listening position that seeks to maximize direct energy to room energy ratio.
 
You don't seem to be grasping what "beaming" means. You could have a speaker with 90 degree beamwidth at 20KHz that would be beaming if the beamwidth at 2KHz was 180 degrees.

It is the narrowing with increasing frequency that the term refers to. If you want or are happy with a +/-15 degree window great. If it was the same beamwidth down to lower frequencies it would not beam.

The DI shows this the best. This needs some manual intervention to get out of ABEC so it isn't often shown.

The difference between what will be heard on axis and what will be heard or reflected back off axis.

Totally agreed.

Narrowing directivity with increasing frequency is the fundamental issue. As fluid says, looking at the DI shows this best. Almost always, the narrowing directivity really increases in the top octave (i.e. 10 to 20 kHz.) It can be so narrow above 10 kHz the beam is like a pencil light width (1" diameter beam) focused at your ears. Move your head inches and there is a change in tone and a change in level. This is what is meant by "head in vice" listening position. Even with time alignment, I wonder how/what the image will integrate/sound like at 1 meter distance... Will be interesting to hear your results.
 
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Very usefull input. Is it also because room reflexions ?

How to do for not having the problem when one moves his head at the sweet spot 3" inches left or right? Narrow sweet spot is a real pain for the pleasure of the listener...
How to see it at looking at a spl curve from 0 to 60 degrees off axis, please ?
 
How to see it at looking at a spl curve from 0 to 60 degrees off axis, please ?

Your best bet is polar response curves and DI. Here is a 2344 CD horn vs a more traditional Altec 511 horn. It's really easy to see the beaming especially in the vertical axis. The 2344 horn has a much larger sweet spot and very stable imaging because of the very smooth and linear DI curve which craps out in the last octave as expected.

Rob :)
 

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Do you consider vertical axis beaming does really matter? As far as I understand, EQ can solve this issue.

Hello Plasnu

Have you ever done the stand up sit down test and heard the upper octaves just disappear when you stand?? I have a set of HEIL's that are very directional in the vertical and you need to be seated so your ears are the same height as the HEIL. Is that an issue?? Horizontal is more important IMHO.

As far as EQ vs directivity?? With single drivers directivity is fixed and EQ cannot change it. It's the actual physical properties that determines what a horn or drivers directivity will be vs frequency .

Rob:)