Midrange horn design, cone-driven - 201

Maybe my mouth is too sharp and creates diffraction
Probably. But you don't have to speculate. It it easy to test:

Just cut some heavy cardboard, and tape it to the horn mouth to make "wings" on the sides. Then put a box on top of the horn, to act as a crude vertical baffle extension - it doesn't have to be perfect.

See how that measures compared to no wings / no baffle extension. If there is some improvement, then you will have given yourself proof that making a bigger mouth (smoother transition) has merit.
 
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Hello, I made a basic sealed box for the BC 6md38... Same fuxxxx problem. So I said damn ! I moved the sliding acoustic panels I am working on and this solves the problem...
Room treatment is something!

But yes, starts with getting the right baffle lol

I am also sorry to say that with no phase plug it is very difficult to go beyond 1500khz and it is more difficult to time align the compression driver
 

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Hello again.

I have been investigating and comparing sealed boxes / waveguides.

Today I compared JBL waveguide with BC 6md38 and my custom waveguide with PHL 1140.

The bc on the JBL is not bad, gives less boost to the lows so would need less EQ. My minimal adapter makes the highs roll off start around 1400 hz. What is strange is that the lower roll off is quite fast at 500hz.

Mine is a bit bigger and a bit deeper, I tried to copy the JBL waveguide before having it based on pictures and dimensions. the couple waveguide PHL gives more boost to the lows and the roll off is less fast, I can cut it at 400 hz. My waveguide throat is 125mm against 100mm for the JBL.

I think it is very difficult to master a small back chamber. I will keep something like a regular sealed box.

I think I would like something between the 2 like Genelec Waveguide. kind of JBL waveguide but truncated to have throat equals to SD.

I only listened to music with PHL custom waveguide against BC regular sealed box. I think the PHL is an an excellent driver, the alliance with the Faital HF108R sounds like a bigger compression driver, which is not the case on the other setup. Voices are real and articulated and drums are intense.
 

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It might be that conical flare (flat wall for sides) is used for one dimension, so in order to maintain the area expansion, the other dimension needs to be reduced in some points.

Have you considered Hornresp to simulate and produce dimensions for the horn. It gives you the choice of width flare (con, exp, uni) and will export the dimensions of a horn (rectangle, symetric, petal) to a CVS. It's an excellent tool and free courtesy of @David McBean and can be downloaded at Hornresp .