Acoustic Horn Design – The Easy Way (Ath4)

Ok I only enabled output.abecproject and it doesn't show any error now. But when I'm importing project to Akabak it gives an error. And it doesn't export .csv either:

ERRORS ------------------------
(12) Script problem at identifier "Elements - SD1": Unknown
Problems resolving RefElements=
 
Hi

@mabat
I did as suggested and edited the 2 nodes. Well...it makes a "slight" difference.

Original script with horn back going through driver membrane:
1737569823840.png



With the 2 nodes edited:

1737569892772.png


Difference in 3D view in ABEC:
1737569976173.png



1737569942113.png


It is point 167 & 168

Please ignore the horrible dispersion. Just the results of trying around more and more weird values and beeing confused by their results before you gave me the hint how to solve the problem.

Is there any chance this can be changed in script directly? Open nodes.txt for every iteration is making each iteration x2 the time....
Maybe easiest to change my source contours script somehow? It has point in + an - direction of z set point...
Source.Contours = {
zoff 0
point p1 -1.5 0 1
point p2 -2.3 5.3 1
point p3 -3.7 10.5 1
point p4 -6.8 17.7 1
point p5 -16.9 34.8 1
point p6 -25 44.6 1
point p7 -23.4 48.3 1
point p8 -4.5 77.1 1
point p9 5.1 86.1 1
point p10 0 92.2 1

line p1 p2 1
line p2 p3 1
line p3 p4 1
line p4 p5 1
line p5 p6 1
line p6 p7 1
line p7 p8 1
line p8 p9 0.8
line p9 p10 0.5
line p10 WG0 0
 
For the purpose of this particular simulation, you could try this (the shape can be different):

 
The A520 loads my JBL2452 so well. Ended up with a 500Hz crossover on my mock-up speakers and it sounds really good as well as having low distortion. Maybe you are able to test one crossed even lower in a bigger horn? On vacation, can post measurements later.

Thing is I have never crossed any JBL 4" driver lower. Not in a gigantic JBL 2360 horn nor in a Le Cleach 200 Hz. (Almost a meter wide). I do however cross lower with a 2490 in a way bigger horn.

For me an A520 looks positively smallish and compact. Really thankful for this new "best" in freestanding horns. Having the loading of a Le Cleach 270 but beeing way smaller, sounding and measuring really smooth even in the top octaves while beeing rather constant in directivity as opposed to the beaming of a JLMC the A520 is a killer. That said Im dead certain there will be a bigger one in the Bambu printer as soon as I get home. How do people stand holidays longer than a weekend?
 
Hello folks,
I also have a problem with ATH4. I get an error message when importing the .abec file into Akabak and the import is accordingly faulty.

This is the error message when importing the project file into ABEC
ERRORS ------------------------
(12) Script problem at identifier "Elements - SD1G0": Unknown
(16) Script problem at identifier "Elements - SD1D1001": Unknown
(23) Script problem at identifier "Elements - SD1D1002": Unknown
(30) Script problem at identifier "Elements - SD1D1003": Unknown
(41) Script problem at identifier "Infinite_Baffle #3": Unknown
Problems resolving RefElements=
Problems resolving RefElements=
Problems resolving RefElements=

This is my .cfg file:
; --------------------------------------------------------------
; Horn geometry

R-OSSE = {
R = 40
r0 = 17.135
a = 60
a0 = 13
k = 1
m = 1
r = 1
b = 0.03
q = 5
}

; --------------------------------------------------------------
; Acoustic Source - Bliesma T25B

Source.Contours = C:\Program Files\ath4\cfg\dome.src
Source.Velocity = 2

; --------------------------------------------------------------
; Transducer LE Model

; LE = <LE_script_file>

; --------------------------------------------------------------
; Basic Geometry

Morph.TargetShape = 0
Mesh.AngularSegments = 32
Mesh.LengthSegments = 20
Mesh.ThroatResolution = 5.0
Mesh.InterfaceResolution = 8.0
Mesh.InterfaceOffset = 5.0

; --------------------------------------------------------------
; General Simulation Parameters

ABEC.SimType = 1
ABEC.f1 = 1000 ; [Hz]
ABEC.f2 = 20000 ; [Hz]
ABEC.NumFrequencies = 40
ABEC.MeshFrequency = 1000 ; [Hz]

; --------------------------------------------------------------
; Observations

ABEC.Polars:SPL = {
MapAngleRange = 0,180,37 ; 0 – 180 deg with 5 deg step
NormAngle = 20 ; [deg]
Distance = 3 ; [m]
}

; --------------------------------------------------------------
; Program output

Output.ABECProject = 1
Output.STL = 0

; --------------------------------------------------------------
; Reporting

Report = {
Title = "horn example"
Width = 1600
Height = 900
}

And this is my driver file
;Bliesma T25B

zoff -2
point p1 4.239 0 2
point p2 0 12.5 0.5
point p3 -1.003 13.76 0.5
point p4 0 15.02 0.5
point p5 0 17.135 1

cpoint c1 -16.311 0
cpoint c2 0.29 13.76

arc p1 c1 p2 1.0
arc p2 c2 p3 0.75
arc p3 c2 p4 0.25
line p4 p5 0
line p5 WG0 0
I would appreciate any help

Greetings poiy
 
Tritonia-S prototype for verification, from the printer directly to the speaker stand -

(roughly 0 - 50/10deg)
1737658929602.png


This is of course absolutely not how it's supposed to be used, but I know people will use it like this anyway, so why not.
It's certianly not a complete disaster, which I assume is due to the rectangular shape. Measured with the Peerless DFM-2535.

1737659211771.png
1737659325512.png


In an enclosure this should be textbook. Printed in one piece, essentially, this is a no-brainer.
 
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