Groundplane Dipole CBT

[AllenB]

It does address the usual downside to a vertical monopole line array, that of plenty of vertical directivity and nothing much horizontal. The sides are going to represent more space than the rear radiation. Could the rear perhaps be reduced at the focal point and still allow nulls to develop at the sides?

 

[OllBoll]

It does address the usual downside to a vertical monopole line array, that of plenty of vertical directivity and nothing much horizontal. The sides are going to represent more space than the rear radiation. Could the rear perhaps be reduced at the focal point and still allow nulls to develop at the sides?

The side nulls work in a dipole cbt, the rear response is reflected down into the floor so you have to lie behind the speaker to hear it directly. (I have walked around my prototype)

But in practice since the overall energy is same on front and rear dispersion won't the rear dispersion just reflect around the room? Keele predicts that the pattern is mirrored to the rear but with the center point in the focal point on the floor behind the speaker.

 

[AllenB]

Presumably like this.. (The bottom line is the floor, one curve is the speaker and the other is the mirror)

 

[Juhazi]

Dipoles need some free space around and a solid front wall to get best reflected sound tonality. How this happens with the cbt in a domestic (small) room is the question - even more than with "normal" dipoles. CBT's backside vertical pattern changes rapidly and is directed down 45deg...