Quote Originally Posted by jneutron
The answer is far more detailed.

The reason a horn does what it does is it couples the energy of the source to that of the room much like a transformer. A small surface vibrating at 20 hz, for example, does not couple it's energy output very well to a room. By using a horn structure, the expanding energy with the compressible media (air) is allowed to slowly convert (as it were) to the impedance of the room.

A room corner, by it's nature, will do this for any transducer that is put there, for frequencies where the walls can be (seen) by the expanding energy. The K horns use this fact to allow the corner to act as part of that waveguide/transformer. So, both horns and direct radiators/ports/T lines/whatever...will see that enhancement when they are put into the corner...the K's just require it as part of their design.

A room will have resonances at specific multiples of the base frequency, in all 3 directions. Corner placement of any transducer will still excite those modes, regardless of the cabinet type.

Putting a speaker away from the walls does not prevent excitation of room modes, unless of course, placement is at a node. There is a complex relationship between where the transducer is within the space, the coupling efficiency to the space as a result of proximity (or lack thereof) to the boundaries..very complex.

For sound frequencies where the walls are part and parcel of the horn waveguide, there can still be coupling to room modes.

Your explanation regarding horns, room resonance, and such, was a curious mix of actual fact, and stuff that... while incorrect, can be useful for guidance in setting up systems..many times, what is taught is not correct, but has a more intuitive feel to it...giving people who don't have the math or physics skills the ability to do their job well, while not burdening them with the real information..and yes, the explanation I just gave is also a simplistic one, but arguably at the level that all here can understand.

I see the two of you arguing along these lines, and am getting very bored with it..

I miss my K horns..

Cheers, John
John,
I really appreciate your response. I don't work with full range horn loaded speakers, so my understanding of how they interact with room boundaries is very limited I must admit.