Horns, straight sections

[jnb]

I'm thinking of using straight sections (say 3 feet) of PVC pipe in a horn early were the taper looks kind of straight. This would be to simplify the process of making the horn long, which I'd like to do.

Would I be better building a shorter, better optimised horn or is this at all beneficial?

 

[GM]

It will roll off the low end and alter its HF response.

GM

 

[jnb]

Thanks, GM.

Then could I reason that a given diameter of pipe could be used for a section provided that the CSA was within a percentage of the target? Such as 20 percent, perhaps?

 

[Brett]

Mardi Gras is coming up. Straight horns are not allowed.

 

[jnb]

Mardi Gras is coming up. Straight horns are not allowed.

Yes, it's best to avoid resonance excitation.

 

[Brett]

Yes, it's best to avoid resonance excitation.

Depends upon you're perspective upon such things.

Where are the D cells?

 

[jnb]

Annnyway , I've been looking at the tapped horn as an alternative. It's my first, thoughts are welcomed.

Tapped horn post

 

[GM]

Thanks, GM.

Then could I reason that a given diameter of pipe could be used for a section provided that the CSA was within a percentage of the target? Such as 20 percent, perhaps?

You're welcome! Not really, less is always less when it comes to horn design in that what makes it work is the constant expansion, i.e. a resistance when the signal is in rarefaction, so a straight pipe is like running place, you get a lot of pumping action, but not much gain for the effort.

That said, approximating a low flare frequency hyperbolic using simple conic sections every half octave of axial length works good enough, making it easier to lay out/fold/build.

GM