horn shape

[seti]

Exponential

Tractrix

Conical Horn

Round horns

I know exponential, tractrix and conical are just the shape of the curves. Most of these can be either round or rectangle or whatever. I am very familiar with exponential as are most heritage owners. Also I have spent some time with modified tractrix and really prefer the sound to exponential. The Klipsch cinema modified tractrix horns 402 and 510 are great.

In doing research lately I have stumbled upon Oris, Ah, avant garde, and Edgar round horns. There seems to be a very fanatical group into this sort of round horn. They claim a round horn does not change the wavefront as much as it leaves the horn keeping it in tact. The claims are numerous such as natural shape for natural sound. Well maybe maybe not. I can not form an opinion because I have never heard a round horn. I imagine with most designs there are advantages and drawbacks for each. What are the strengths and weaknesses of these round horns? Is it snake oil or horn hysteria?

[Mr. RF62]

Thanks Seti for posting this. I have always wondered what the difference was, so it is just the way it is shaped and how the wave comes out. The names make it seem like there is so much more, and that its really so important.

[jdm56]

"Thanks Seti for posting this." -RF62

Amen to the above. It seems only logical that a round or conical horn would have fewer reflections within it due to the shape of the horn more closely resembling the shape of the expanding wave front. If so, it would logically follow there would be fewer colorations due to reflections inside the horn. Assuming that's all true, the round horn still wouldn't necessarily sound better than a square or rectangular one! All I know is the best sounding horns I've heard have all been exponential.

[seti]

Cool I'm glad I wasn't the only one wondering. I also wonder what it is like without the horizontal and vertical not being as controlled? I hope some forum guys have experience with these horns.

[bodcaw boy]

hey seti,

it's not the curve that matters; it is the area expansion that makes it an expo, coni, or tt or whatever. the equations nail down one degree of freedom and that is length. the width and height are totally up to you. as to round and rectangle or octagon or whatever, it would seem logical that a round horn would disturb the bubble the least but if you change the exit geometry of the compression driver to a non round shape then the horn should follow. having said that, i have played with a few horns and as long as you are careful with the bubble, you sure can find ways to manipulate the wave.

some things i have found are that slight variations in the expansion of the area make big differences. i mean look how close the expo and tt curves are. throat transitions are also game changers.

[seti]

hey seti,

it's not the curve that matters; it is the area expansion that makes it an expo, coni, or tt or whatever. the equations nail down one degree of freedom and that is length. the width and height are totally up to you. as to round and rectangle or octagon or whatever, it would seem logical that a round horn would disturb the bubble the least but if you change the exit geometry of the compression driver to a non round shape then the horn should follow. having said that, i have played with a few horns and as long as you are careful with the bubble, you sure can find ways to manipulate the wave.

some things i have found are that slight variations in the expansion of the area make big differences. i mean look how close the expo and tt curves are. throat transitions are also game changers.

I was hoping you would see this thread Roy.

You see I think I have the basic concept down only to learn I got it wrong. Oh well at least I learn. Thanks for the answer. I may have more questions after this sinks in. When I saw these horns I thought of your bubble explanation but also I know that you can't just assume. Proof is in the hearing.

"width and height up to you" wow so have you made a modified tractrix wider and higher than the 402?

Have you sampled any of these round horns?

[Don Richard]

In a round horn the vertical and horizontal polar patterns are the same. It is often beneficial to reduce the vertical polar coverage, especially in a room, to reduce reflections. I've noticed that oval waveguides are being used in several newer designs, presumably to address that issue. A smoother horn shape should also improve freq response and reduce diffraction effects.

[seti]

In a round horn the vertical and horizontal polar patterns are the same. It is often beneficial to reduce the vertical polar coverage, especially in a room, to reduce reflections. I've noticed that oval waveguides are being used in several newer designs, presumably to address that issue. A smoother horn shape should also improve freq response and reduce diffraction effects.

The guy that designed that conical horn above also designed this horn for Japanese theaters. He says it is a conical radial horn. It uses TAD drivers which is how I found the site. They are pricey but they look built to last.