I’m going to build my first horn system, about 60 – at least 6000 Hz. (Under that sealed active subs, above that maybe Aurum Cantus ribbons).
Most desired qualities: transient response, dynamics & detail.
Budget: lowish with good quality.

Plan A is look for a horn to put my 12” JBL 2202H's in, covering 60 - 400 Hz. A bit more would be better, as my mids would be happier from 500 Hz up.

A straight hypex 68" (172 cm) should give close to 60 Hz, but is a tad long. When I saw 15" JBLs in a U horn the other day http://hem.passagen.se/sajberrapid/50hz.html, I thought the smaller size and ability to stick them where the back wall meets the side-walls should make integration easier. I tried to contact Mattias for design info, without success so far.

Option B is just run the JBLs up to about 150-250 Hz, then use some 10" PHL 3451s that I have, up to about 800 Hz, then a 1.5-2" driver in a horn all the way to 20 kHz.

If I go Plan A, it’d be more flexible with either a U horn (how to design it?) or a folded horn. To get extension to 500 Hz, I’d need one with either very well deigned reflectors, or curves.

Bill Fitzmaurice’s DR horns have curved bends, eg www.billfitzmaurice.com/plans/product_info.php/products_id/3 but are a double curve, and intended to hold arrays as well, so degree of difficulty to build is more than I need.

Is there a single curve folded design around?

Any comments are welcome.

Thanks!

• Folding, bends, reflectors, etc.
  
• Simulation

> I can tell you that there are several suitable designs.

Great! Could you name some for which DIY plans are available (and any comments on tuning them).

(and maybe the odd one up to say 400 Hz)?

Thanks

To add to that, I’ve read Bill Fitzmaurice saying:

“The DRs are the only folded horns that I'm aware of that can go as high as a straighthorn but still deliver down to as low as 80 Hz in a relatively compact package.”

The DRs are more complicated than I need, so do you have a simpler plan for a DIYer?

Thanks

What I would propose is a simple conical horn. The bandwidth you require is mostly midrange, so you might consider a higher crossover point which allows a smaller horn. Naturally, deeper extension will require a larger horn. If you plan to use subs underneath, you could raise your midrange horn crossover point an octave or so, which would make its size requirements much smaller. Then you could go with a straight horn, which is about as simple and pure as it gets.

Thanks, before you send any plans . .

I didn’t mention it, but I have a pair of JBL 2202s, that are Fs 50 Hz, Qes 0.17 & Fhm 588 Hz. To get value from them I wanted to cross to a mid horn at 500 Hz. If I cross at only 200 Hz I’m throwing away a lot of their potential. (I’ll use a sub under about 70 Hz).

I could sell them, but they’re very good.

Yes a simple conical horn could be perfect above that, and have a driver in mind that’s good over 500 – 6000 Hz.

Do any of the plans, by virtue of smoothness one octave into the lower mids, fit this need?

Thanks