Need info on designing front/rear loaded bass horns

[jSisco]

Does anyone out there know, or know where I can find information, about designing my own front or rear loaded bass horn. I've found a couple of sites that have pictures of manufactured enclosures, but none that give me the equations on how to design my own. I want to use the horns for their efficency, if there are other options around for high output sub systems, I am open to suggestions. Thanks.

 

[fragman56]

Hi,

Have you tried www.melhuish.org? I think that is the address of the single driver website -- some formulas, etc.

Good luck,
Rick

 

[mikee12345]

that melhsuish site is good..

also use mcbeans program to model horns..

http://hem.passagen.se/sajberrapid

www.prosoundweb.com/lsp
the labsub 30hz horn sub(2x eminence 12inchers)

if there are other options around for high output sub systems, I am open to suggestions

the horn is the ultimate.the most accurate reproduction.
(biggest size)

 

[Remy]

Hi,

Front loaded bass horn have big problems, huge length of the horn for really low frequency, and some kind of "delay", time of establishment with big horn.

Rémy

 

[mikee12345]

remy : the delay is usualy perhaps 15ms for a labhorn=

this is considerably less group delay than a normal ported box
any group delay ofcourse is unwanted/

?

 

[Remy]

Hi Mikee12345,

I'm talking about huge horn, to reproduce very low bass frequency, sometimes with a compression driver(like 160D ALE compression driver or models from Tanaka), in this case, you can hear the time of etablishment of the wave in the horn, quite hard to describe it with my poor english, i'm sorry. But this solution for bass reproduction have some great quality, first the weight of compression driver diaphragm vs a bass loudspeakers, the diaphragm move faster, the sound is more complex, lots of details you can't hear with electrodynamic loudspeakers, distortion is lowered. But the price of these basscompression driver are hum... really too much expensive Be carefull if you build a horn longer than 1 meter, that's not easy..

Rémy

 

[slowmotion]

Hi all

I have built a lot of bad sounding basshorns in my time,
they are really difficult to get right
Whenever you start to compromise on size,
or start folding it, you really have to know what you are doing.
I don't.
They all made good firewood

I did build one very good basshorn once , just as a test,
it was straight , about 1/3 size , about 40Hz , mono.
Enormous , the thing was.

Sounded real good. Totally impractical, though .
Filled the whole room . I dismanteled it.
Was just to big.

So , it can be done, and the dream is still there

cheers

 

[MJK]

My MathCad worksheets will model both front and back loaded horns. You can input very flexible geometries, coupling chambers, and fiber damping to see what SPL response you can achieve. The application note with each download will help define the variables required as input to the worksheets.

The models have been correlated against AJ-Horn and HornResp and work very well. I have not as yet spent a lot of time trying to understand the design guidelines for either type of horn but you can model just about any geomtry that you have in mind and see a fairly accurate prediction of the response.

Oh, they are FREE to run using the MathCad Explorer 8 download.

Hope that helps,