Rubic Horn

You might laugh but he has. Get him to post up some pics of some of his stuff, its radical.

 

Yes Adam, a wall like a floor will reinforce the output as you now have the speaker and another virtual speaker or mirror of the speakers output adding to it. This is providing the speaker is close enough to couple in wavelength terms to the adjacent floor or wall. So a horn that requires a mouth of 5000 sq cm to have a certain low cutoff can have this figure halved if its in contact with the floor or quatered if its on the floor and against one wall. Hence half space, quater space and so on. So at what point does a stack of speakers all combining in phase change from one operating condidtion to another. Well, if the stack is on the floor then its in half space, but I'm not convinced the more cabs you add the more it operates like it was in quater space. It will happen to a certain extent but I think you still have a new larger speaker with a longer horn in half space. I never automatically change from half space to quater space or eighth space if I model moe than one speaker. For me its just a larger speaker with a longer horn and bigger mough if its a horn. Its still in half space. Likewise I alwyas model mid tops in free space even if there are 8 of them. Its still a speaker, all be it a large one thats in free space. Its a difficult question to answer and I have a couple of times on here before, but a stack of speakers operating condidtions don't change as much as you think unless you go very big. The bigger the speaker and the larger its radiating surface is the less it starts to obey the inverse square law. Why, well you are more likely to be in the near field of a sound source if it is marginally larger than you are. Its like you are physically nearer and will also visually look like this as the stack grows.

 

Its a dabte that still continues. I think you still have a larger speaker with increased coupling to the floor, a longer horn path and bigger mouth if using horns and the increase in efficiency that brings, but still working in the same space. You can also add any effects brought about via any decrease on the inverse square law if the stack is large enough. But one thing thats doesn't happen is that you automatically add 6dB everytime you double the amount of speakers. You will get 3dB from double the amp power as a result of the lower impeadance and only if the amp delivers twice the output into the new lower load, but you can never get 3dB from a doubling of sensitivity. So be careful when knowing the output of one cab and then addding 6dB everytime you double the amout to work out the new combined output. It will never be as much as you expect due to cabinet losses which destructively combine to reduce the sensitivity and the fact that most amps don't double there output into half the impedance.

 

 

Yeah,

 

I thought more like a douche bagged version of Ali G........

 

A few years ago we designed a similar concept (M-horn, see www.speakerstore.nl) but this was a folded frontloaded horn instead of rearloaded. For people who have little money but enough time this is an excellent solution to get much bass for little money. We also chose to cut the 18" horn in two modules for easy of transportation.

 

As far as I know only two people did build our M-horn (they were impressed with the loud deep bass) the main problem is no one was able to find the perfect solution on how to couple both parts of the horn. And how to prevent air leaks and rattles when the modules are on top of each other.

 

Best regards,

 

Walt