Acoustic Horn Design - The Practical Way

Thank you very much for sharing, this is very interesting to see. Nice work.

Now it will be extremely interesting to see the simulation after you include the dome geometry in the throat (with Ath 4.6) - how good the match will be. So far my experience is that the surround of the diaphragm in the throat is not a good thing but then the measured data you show are pretty good, at least compared to what I have seen in the sims. It is also possible that the real-world situation is actually better than the with the theoretically rigid dome - that's one of the things to be seen.

Thank you.
It will be interesting to try the 4.6 version and see if we can get a better correlation between sim and measured result. Looking forward to this.
I have done some variants with throat ID from 27mm (completely covering the surround) and out to where the groove for the grille is at 41mm. So far I like the 31mm version best.
 
Nice, I suggest you to use VitiuxCAD tool to convert pir files to the frequency domain (a breeze to use by the way) and then you can see polar maps at your convenience

Thank you for this tips. I have not used this before.
 

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So I did another print based on the simulations you showed with a conical expansion from the throat.
I kept the overall outside dimensions the same as in my previous versions, but the depth is reduced to 52mm.

Code:
; Horn Geometry
; -------------------------------------------------------

Throat.Diameter = 31 ; [mm]
Throat.Angle = 40 ; [deg]
Throat.Profile = cone
Throat.Ext.Length = 0

Length = 52 ; [mm]

GCurve = SE
GCurve.SE.Exp = 2.3
GCurve.Angle = 50
GCurve.VertScale = 0.75

Term.s = 0.7
Term.n = 4.0
Term.q = 0.995

Morph.TargetShape = rect
Morph.FixedPart = 0
Morph.StretchExp = 3
Morph.CornerRadius = 35 ; [mm]
 

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Directivity could be better above 10kHz, but it's getting quite good in the important range below 10k I think.

Measured in a 600 x 800mm baffle at about 1 meter.
The Vituixcad plot is normalized to the 10 degree curve.
Arta plots is normalized to 0 deg.
 

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Member
Joined 2004
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Ath 4.6 released: #3088

Now you can try to model the particular tweeter used.

Please note that the syntax of the definition file changed since 4.5 - this was again inevitable as too much has changed internally and some items would lost a good meaning. It's not difficult to transfer the existing definitions however - just go throuth the syntax reference in the User Giude. The basic principles remain about the same.
 
i've got it )

Roman, you are free to start a new thread where we can discuss your new project - as it is a shallow waveguide for a dome tweeter I guess it might interest a lot of people. I could contribute with the little know-how I have, or even adapt Ath more for dome tweeters a bit along the way. It would be interesting to watch the development.
finally, everything works perfect! Thank you for your development! I used your soft, Sketchup and Fusion360 for machining. Result looks good. Will see how they will sounds when i'll finished them )
7232dc_5eafb21138de4e558fe08e6107825b1f~mv2.webp

7232dc_702b1a0ed8d34b71bcb4c128439afbda~mv2.webp

file.mp4
 
my TQWT project with waveguides done

Congrats! So what's the tweeter and did you try to simulate it with the new source modeling capabilities in Ath 4.6?
Once again, thank you Marcel for your ATH soft! Unfortunately 4.6 don't work on my laptop, I don't know/understand why... But with a previous version and Fusion 360 you can see the results:
7232dc_4f79191d76fa44269c05a5349acd9dd7~mv2.webp

New TQWT speaker by inception
 
Hello again,

I have finally printed two TinyRs for my Linn Unik speakers, actually I have taken the file generated in the demo exported to Fusion, divided into two halves and printed in a 240mm diameter delta. The first half was made in ABS, with this material I had warping problems, I made the other halves with PETG. The result is quite correct, I have glued the parts with cyanoacrylate with activator and the joint is very good, it has resisted some fall to the ground. The first unit I taped together and put it in the unit to test, the second unit is a bit more elaborate, I have applied a coat of polyurethane primer and now wait for the finish color coat.

At the level of results I have to say that these small speakers are in my workshop of about 60 m2, the effect of the horn is a curious improvement in reproduction, from here I hope to make other prototypes with a little more previous analysis and looking for results , It has been a good test to evaluate the use of the 3d printer for the manufacture of horns.

Thanks Mabat for this awesome app
 

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