How shallow can a waveguide be?

[jasonb]

How shallow can a waveguide be and still be effective at eliminating diffraction?

I have 2" full range drivers in my car that are in custom pods in my sail panels (top of the front of the doors). I want to control off axis dispersion and mostly eliminate diffraction and reflections off the edge of my pods and surrounding dash parts. With the way things are currently set up I have room to build a pair of shallow "waveguides". The inside would be just large enough to clear the drivers surrounds, and I think I could get away with a 1/2" depth and inside radius. These full range drivers will only be ever used down to 900 hz or so at the lowest. Will a "waveguide" this small do anything to control dispersion and help prevent diffraction?

Thanks,

Jason

[Pete Schumacher ®]

How shallow can a waveguide be and still be effective at eliminating diffraction?

I have 2" full range drivers in my car that are in custom pods in my sail panels (top of the front of the doors). I want to control off axis dispersion and mostly eliminate diffraction and reflections off the edge of my pods and surrounding dash parts. With the way things are currently set up I have room to build a pair of shallow "waveguides". The inside would be just large enough to clear the drivers surrounds, and I think I could get away with a 1/2" depth and inside radius. These full range drivers will only be ever used down to 900 hz or so at the lowest. Will a "waveguide" this small do anything to control dispersion and help prevent diffraction?

Thanks,

Jason

In short, probably not much effect.

And because you're already set up in a small "pod" you're about as omni as you can get from a directivity standpoint.