Sub horn throat size

[Augusts]

Hello!

I am building my first horn. I wanted to ask a question, is 100sq cm or smaller - good for a bass horn throat if I use a throat chamber? Simulation shows that it is good but Im calculating that would be 60cm x1.6 cm that sounds a little crazy. Im using a 12 inch driver.

Thanks
A

 

[zettairyouiki]

For a horn, your throat cross section divided by your cone area is your "compression ratio". There are various general recommendations for what your CR can go up to. I'd say for a strong driver, your CR can be as high as 4. Others might have different recommendations.

This is for high excursions in high power cabinets. If you intend to run the horn at lower power levels, you might be find with going higher.

Be aware that boundary layer effects apply here. A throat that is 60cmx1.6cm is going to have a lot more resistance than a throat that is say 16cmx6cm.

 

[zettairyouiki]

For a horn, your throat cross section divided by your cone area is your "compression ratio".

Correction. Should be the other way around.

Cone Area/Throat Area

 

[whgeiger]

Note:

[Sd] is a projected area, which is smaller than the actual surface area of the moving system. Typically it is the surface area of a virtual flat disk whose circumference traces to include slightly less than 1/2 the width of the surround. WHG