Why Arai horn website ?

Yuichi Arai is the designer of Arai horns, a 95° hyperbolic constant directivity horn with fins for use in a room at 2.5/6m listening distance with compression driver

I manage to put all useful information with Yuichi Arai personal agreement about Arai Horn here, two model in particularity :
- Arai 480 for 1" driver
- Arai 290 for 2" driver or 1.4/1.5" driver with the right adapter.

Only with fins, reason is explained in Horn Design section.

In a way it's the modern evolution of sectoral horn like Altec Lansing 811B, mainly thanks to a good way to manage fins in Arai.

Arai instruction have some simplifications, some rounded number in final PDF as seen in Horn Design section, mainly because theses plan was design to be build by hand.

Disclaimer :

Yuichi Arai had made a website that is down now and he will not rebuild it, Yuichi begins to be old so he give me his full agreement for all the content that concern horn and continue the website. 

I'm using only the content relative to horn, I consider that there is enough modern information about measurement and tooling on DIY forum.

You can find more information buy buying Yuichi book, there is a Kindle version :

I have no profit on this book and I make no profit on the website.
I do it for DIY community on my time and my money (for the domain name).

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