Acoustic Horn Design – The Easy Way (Ath4)

What I will never understand is the use of a strongly beaming horn in order to get to 300 Hz and then crossing the driver over at 500 Hz with a 24dB/oct filter.
Well that has to do with system integration and room interactions. Btw I now changed the crossover point to a lower value. And I like beamy speakers, assumingly. It is a compromise of course, you get more of a studio monitor-like presentation, a headphone experience without having the sound in your head. But mind you they are not that beamy, such that you need a vise to keep your head centered, but obviously the center place is the best. Like a F1 car. There is some wiggleroom in case you need to reach the bag of chips :sneaky:
 
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But mind you they are not that beamy, such that you need a vise to keep your head centered, but obviously the center place is the best.
That wouldn't be the main problem with beaming sources (I don't move a lot during listening either). The bigger problem is that with a beaming source the early reflections contain only very little high-frequency energy. Don't ask me why but this just doesn't sound as natural as when these reflections are spectrally more similar to the direct sound. There's nothing you can do about this in the room - to regain balance you would have to absorb lower frequencies but not the higher ones - a tough task to do.

I do but scattered around in different files. I'll see if I can share them.
That would be great!
 
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The bigger problem is that with a beaming source the early reflections contain only very little high-frequency energy. Don't ask me why but this just doesn't sound as natural as when these reflections are spectrally more similar to the direct sound. There's nothing you can do about this in the room - to regain balance you would have to absorb lower frequencies but not the higher ones - a tough task to do.
In general you are right, but I addressed these problems with room treatment. Yes it was tough but worth it i.m.o. Diffusers combined with absorbers at the right places are your friend here.
 
The only practical way to overcome the lack of radiated HF energy is to sit in so strong direct field that the reflections will add only marginally, and then the directivity of the source is of course much less important (to irrelevant). If you like that kind of headphone sound, good for you. Otherwise it would be a lot more difficult :)
 
If you want to try them out I could help with then profiles.
Thank you for the offer, very nice! The absence of first reflections does not bother me. Well, I did use a biradial tractrix horn before, but in the end I ditched it because of the pattern flip, the round/petal horn I now listen to sounds more natural to me. I am able to create horn profiles myself -but again thanks for your involvement.
 
Working on a second pair of Le'Cleach horns. Unfortunately I need to replace the nozzles of my printer as they have worn out after several km's of filament :( Still 11 parts to go...
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Hornresp gives an exact solution which is slightly different in the mouth when compared with the older spreadsheets , the "canonical" use for a horn like this has been T=0.7 and using it above around 2x cut off. I attach a comparison between the spreadsheet and Hornresp (units not correct) for a 340Hz/T=0.7 horn with a 2 inch mouth and the exported horn geometry profile from Hornresp.
 

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Thanks! I quickly put it into Ath&ABEC. Overall, no surprises -

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I like the impedance, hate the beaming.

(It could probably be approximated by a R-OSSE profile quite well, I may try that some day. I'm sure several very similar horns have been shown in this thread already - perhaps something like this: https://www.diyaudio.com/community/...-design-the-easy-way-ath4.338806/post-7337185, which probably wouldn't suffer as much from the "group delay issues" around cut-off, so often mentioned.)
 
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Freestanding 46 degree B&C DE111 R-OSSE over an 8 inch Dayton DC200-8 in a 9x9 inch enclosure. Waveguide can be moved up and down to find the best center-to-center distance relative to crossover.

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I don't know how to make crossovers. I'm learning in VituixCAD. I create the crossover then export it to Equalizer APO. That allows me to hear the crossover changes immediately. I'm listening to high order crossovers to get a feel for it then I'll back off to lower order crossovers more suitable for passive designs.

Practice var3 XO-schema-3.png Practice var3 Six-pack.png


As expected, waveguide performance matches the simulations.


Practice var3 Directivity (hor).png 46_8inch_DE111_normalized_20.png


I've listened to stereo music and watched a movie using only one speaker as a center channel. Music is very good but I'm most impressed with how well it works as a center channel for dialog intelligibility.
 
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