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

Looks similar to EV9040A:

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Really? I Do not see much similarity. My horns Do not have such sudden flare changes and I am quite sure that the profile formulas are totally different.
 
The first Iwata (Pacman) looks best but I realized It is that flat plane on the top and bottom of the lip that I am chasing. So even if the way you are generating these Horns can't make the flat lip, I can take the model into Fusion360 and make it flat.

So what do you think? Can you make this more like the Jericho 45 ie, 35" axial length, 20" height, without being crazy wide? Maybe 30" wide or less.

The 2nd one, is it me or is the radius bulging on the lip? I'd like that to be flatter like it is on the Pacman.
 

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camplo, you want the (mathematically derived) profile that matches your driver's wavefronts.
According to the designer, the diaphragm and phaseplug of the Axi2050 were specificaly designed to emit spherical cone shaped wavefronts.

These are the horizontal and vertical profiles of a JMLC IWATA horn (similar to the images above) with: Fc = 100Hz, Length/Height ratio = 3,5,
sphericity of the waves at the throat = 1 (whereas a plane wave front = 0).

You would probably be the first person ever to construct such a gigantic horn for a 2" exit compression driver.
I entered the "most convenient" values, which would result in the smallest mouth possible, if 3 (W) x 1.8 (H) x 1.8 (D) in Meters can be considered small ;).
 

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The JMLC - IWATA horn features an elliptical cross section.

These images show a 220Hz JMLC IWATA horn, which is used with a JBL 2482 + Radian diaphragm from 300-350Hz.
 

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However, it seems you could get away with a smaller horn.

Fc: 150Hz -> 120x120x96 cm appears to be usable from 180Hz.


These rectangular JMLC IWATA's were used from 316Hz with Radian 950PBs (At least, it's what I understand from the comments posted in the French forum):

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If I understand, you are saying the best horn will based off a spherical horn? Not as in a round horn but spherical as opposed to jmlc, exponential, tractrix?

So the iwata based of spherical horn is fine? Or to stay to the round shapes? Or the elliptical shape of iwata is not recommended. I think you are saying stick to the round spherical horns. I’m ok with that, Docali has been able to do those well and it is how the first Jericho was born
 
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In the spreadsheet, I choose "spherical wavefront" for calculation of the profiles (H & V).
With some fiddling a point cloud can be produced by computing projections of points onto planes.
Or, even better: docali could integrate the equations into his own tool.

The elliptical shape is the result of blending JMLC math with IWATA math.

An original IWATA horn's cross section is rectangular:
 

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If I understand, you are saying the best horn will based off a spherical horn? Not as in a round horn but spherical as opposed to jmlc, exponential, tractrix?

So the iwata based of spherical horn is fine? Or to stay to the round shapes? Or the elliptical shape of iwata is not recommended. I think you are saying stick to the round spherical horns. I’m ok with that, Docali has been able to do those well and it is how the first Jericho was born

It's very hard to say which shape is "better", because a lot depends on other factors as well.

In your room (even) a 40x20 horn may give very satisfactory results:
 

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With a HP4020 mounted in the big horn and perhaps the 4x10" replaced with some (bigger) drivers, you would end up with a 2-way capable of >130dB ;)
The HP4020 facillitates a crossover from 200Hz.

An externally hosted image should be here but it was not working when we last tested it.
 

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The first Iwata (Pacman) looks best but I realized It is that flat plane on the top and bottom of the lip that I am chasing. So even if the way you are generating these Horns can't make the flat lip, I can take the model into Fusion360 and make it flat.

So what do you think? Can you make this more like the Jericho 45 ie, 35" axial length, 20" height, without being crazy wide? Maybe 30" wide or less.

You appear more focused on achieving a particular look than optimised acoustic performance.
 
Yes, these were made by Franck Delbauve (I believe he lives in Belgium).
The mouth is 1.2m² (1.10 * 1.10), similar depth; 1.12m to the driver's exit, with a round adapter. Cut off is 150Hz, but could be lowered by using a longer throat adapter.

If you search "Delbauve Pavillon melaudia.net", you'll find lots of info in French, so you might want to use google tanslate.

The same guy also made the wooden JMLC-IWATA horns for the European Triode Festival 2013.

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TNT

Member
Joined 2003
Paid Member
These JMLC-IWATA (or similar), can they be mounted in a "sphere" in order to mitigate diffraction at the edge? Is it's dimensions like that it would integrate into a sphere seamlessly?

//
 

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diyAudio Moderator
Joined 2008
Paid Member
Not necessary. The full spiral rollback is a very good diffraction mitigator and takes even less space. This is what these were designed for. Choking up the rollback with any kind of baffle could be audible as a problem and create reflections.
 
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