Acoustic Horn Design – The Easy Way (Ath4)

[mabat]

Please show us, I have my doubts... I don't think it will be as pretty as in the brochure...
(at least not with life size drivers)

As soon as I have the "bend to arc" feature, as I believe this physical attribute is essential and cannot be substituted by delays.

 

[limacon]

https://www.at-horns.eu/release/ath-beta-221114.zip

Two examples attached. You can export FRD data for the individial array groups and than work with that in any crossover simulator (see array1.txt demo). Or you can also work within ABEC manually on the script level (the most simple is to overwrite individual levels and/or delays in observation.txt).

- No LF source/enclosure support yet.

Tried with the array0.txt
Importing whole ABEC project
ERRORS ------------------------
Missing "Control_Solver"

 

[mabat]

I don't know, it works for me, there's definitely a Control_Solver in the solving.txt (must be something else).
I can import both ABEC projects (attached) into AKABAK (3.1.2 b59) without any problems.

Did you use the latest ath.exe?

 

[mabat]

- OK, I need to perform some initial test now before I release it to the world....

- Just from looking at it, I think the top & bottom walls of the horn will screw it up (and will need to be done differently) but let's see.

 

[tmuikku]

wow nice

 

[limacon]

Oh my gosh @mabat - that's wonderful!

 

[Olombo]

Made my day!

I get same error with "missing control solver" while importing in Akabak. Anyway I get the bare basics imported thats enough.

If I want to try another source shape (rectangular) how to define it? source shape=1 and how to define width/height? I once crafted a segmented AMT driver....maybe resurrection of that project now

 

[limacon]

another source shape (rectangular) how to define it? source shape=1

rectangle would be amazing too! Using 3.1.7 b97 here

 

[Olombo]

Limacon: what is 3.1.7 b97???

 

[limacon]

Limacon: what is 3.1.7 b97???

AKABAK (3.1.7 b97) - current download version

 

[Olombo]

I will check version later. Didnt get that ;-)

 

[mabat]

The first quick sanity check.

Circular arc length = 2x850 mm
Half angle = 30 deg
2x28 elements in CBT/Keele's shading
Element diameter = 22 mm
Element center-to-center spacing = 30 mm

Vertical polars:

 

[mabat]

Vertical polars at 1, 2, 4, 8 meters:

 

[mabat]

Acoustic impedances of all the elements:

 

[mabat]

It's fascinating how rapidly it falls apart around 10 kHz. Partly it may be due to the BEM resolution but I guess this is basically how CBT behaves for the given c-c distance.

The bad news is that the simulation took almost 1.5 hour, despite only some 1700 BEM elements. That's probably due to the high number of separate sources (?).

 

[limacon]

Can you add ability for more than 1 column of sources?

 

[Olombo]

@limacon: same Akabak version.

For your center-center spacing that sound real. Thats why I tried the segmented AMT a while ago as distance between single driven elements is then virtually nothing.

Another solution to that problem would be the waveformers for compression drivers. Here you can basically form any shape of the wavefront desired:
https://www.production-partner.de/test/test-ks-audio-cpd18/#VAL
https://ks-audio.com/valtec

Also a non-symmetrical bending is possible that way. Then also above 10kHz you could get nice results.

 

[limacon]

It's fascinating how rapidly it falls apart around 10 kHz. Partly it may be due to the BEM resolution but I guess this is basically how CBT behaves for the given c-c distance.

The bad news is that the simulation took almost 1.5 hour, despite only some 1700 BEM elements. That's probably due to the high number of separate sources (?).

Wine?

https://d1o0i0v5q5lp8h.cloudfront.n...uments/Altra_Max_Rev_A1_DS_v1.05_20220728.pdf

 

[mabat]

Something colourful

200, 2k, 4k, 8k
10k , 11k, 14k

 

[mabat]

Here's the ABEC project. That's all for now. It still needs a bit of cleaning and then I'll release the rest.