So I've always seen dipolar subwoofers designed 'boxless' using one sub on a large panel or two sub's folded.
My question is if 2 opposed sub's (180 degrees) in a shared sealed enclosure, wired to get bipolar radiation, would also have low frequency response limited by panel size? Or does panel size only effect 'boxless' dipole subwoofer designs?
Sorry if that was confusing. Here is a dipolar speaker with dipole 'sealed' subwoofers like I'm trying to describe.
PERFECT8 Technologies: The Point
My question is if 2 opposed sub's (180 degrees) in a shared sealed enclosure, wired to get bipolar radiation, would also have low frequency response limited by panel size? Or does panel size only effect 'boxless' dipole subwoofer designs?
Sorry if that was confusing. Here is a dipolar speaker with dipole 'sealed' subwoofers like I'm trying to describe.
PERFECT8 Technologies: The Point
Dipoles cancel below the baffle corner frequency whereas bipoles sum, so considering the sheer size of LF BW 'bubbles' [80 Hz = ~4316.28"/80 = 54" dia.], the baffles must be quite large by most folk's standards to have any impact on its directivity performance even up through its XO BW.
GM
GM
It's a good question and the answer is yes, it does.
Both drivers will be within 1 wavelength of the other so in practice you will have a dipole in the same way as if it was boxless ( up until the back and front sub doesn't sum anymore, but that is probably higher than it will play ).
You could get the same thing with 2 separate sealed subs and placing them a distance from each other and wire them out of phase of each other. There is, however, advantages of having both in 1 box as you then don't change the pressure in the box which is nice.
Both drivers will be within 1 wavelength of the other so in practice you will have a dipole in the same way as if it was boxless ( up until the back and front sub doesn't sum anymore, but that is probably higher than it will play ).
You could get the same thing with 2 separate sealed subs and placing them a distance from each other and wire them out of phase of each other. There is, however, advantages of having both in 1 box as you then don't change the pressure in the box which is nice.
I don't believe that the sub section of the P8 is dipole. The makers description indicates that it is bipole. They go on to explain the output above 70hz as "traversing cardioid". Must have to do with the delay and spacing between the two 10" sub sources. I wonder what the LF polar response looks like between 70-150 hz.
Yes, sub is bipole (in the passband monopole). Their dipole section starts at 80Hz in this measurement, and stops being dipole at 3kHz!
I could not call this Perfect8, but it is almost as good as it can be... Nao Note and LX521 are better.
I could not call this Perfect8, but it is almost as good as it can be... Nao Note and LX521 are better.
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Thanks for clarifying everything guys!
It makes total sense to me now why dipole subs must be folded. Thanks!
It makes total sense to me now why dipole subs must be folded. Thanks!
Yes, sub is bipole (in the passband monopole). Their dipole section starts at 80Hz in this measurement, and stops being dipole at 3kHz!
I could not call this Perfect8, but it is almost as good as it can be... Nao Note and LX521 are better.
Why do the Perfect8 speakers stop being dipoles above 3khz? 😕
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