Horn sub. wich drivers??

[wuffer]

im thinking of building a horn for sub and found this



the design uses 2 etone 135 but is there some other drivers i can use??

[AndrewT]

Hi,
from what I have read the resistive loading provided by the horn makes the design very tolerant of different drivers.

However, that pic is a bass speaker with seriously curtailed bass at that.
It cannot possibly be a sub-bass speaker with the dimensions of the mouth and length shown.

I'm guessing the mouth is about 15inch by 18inch (1.9ft^2).

Sitting on the floor the bass will start cutting off at about 80Hz.
To get down to 40Hz, the mouth will need to be about 4times as big and you still don't have a sub-bass speaker, just a good bass speaker for music.

Have a look at the Labhorn and the paper about it that Tom Danley wrote. It needs six units stacked on the floor to perform properly down to bass frequencies and it still cuts off at 27Hz.

[wuffer]

thanks.. i have much to learn..
i will read on and look for another design..

[Tom Danley]

Hi

As with a vented or sealed box, you can put any driver in any enclosure and it will work.
Similarly, if you want it to work well, you have to be much more careful, horns are more sensitive to having the proper driver parameters, or at least just as sensitive as other designs.
Your best bet is to find a copy of McBeans horn simulator, get familiar with it and then compare different drivers in your proposed horn.

Also, practical sized bass horns have a frequency response that changes some depending how many you have or how they are positioned relative to a corner or boundary.
For the lab subs mentioned below, 6 will give the flattest most efficient (about 40% or about 108dB 1w) operation. On the other hand, most people that built them use them in groups of two or four for outdoor concert use. In a living room, near the boundaries and in a contained space, one is probably over kill unless its home theater.

The problem with “small” bass horns is the acoustic load the horn places on the cone, changes too much VS frequency leaving a series of peaks and dips for the response.
I found an arrangement I called the Tapped horn which allows the acoustic load and its driving impedance to more or less track each other at its low frequency end.
That allows the size of the horn to be reduced compared to a conventional horn with the same cutoff.

Have fun, horns can be the best of all but are more difficult to make right.
Best,

Tom Danley

[hm]

Hello,

here a few other designs:

http://www.hm-moreart.de/1.htm