Only if you are at the centre of the radiation pattern of the 2 drivers. so if you can mount them on th esides you will achieve this. Otherwise you end up with what i call bipole droop. This can be minimozed with a box wider then deep, or a LP filter at an appropriate frequency on the back driver.
dave
yea, I'm planning on doing them in series so I expect the response should drop about 3db. The woofer is more sensitive so the woofer should cross nicely to the bipole drivers, first order around 500 hz. I was going to do a semi open backed dipole but winisd shows a giant rise and drop in response. A sealed bipole seems to make more sense here.
Basing only on fundamentals.. Say you crossed the rear woofer in a way as to only include radiation that wraps to meet the front woofer, and your interest in this case is only the baffle effects. What you have is no different to common single driver BSC or 2.5 way. The main advantage of 2.5 way is convenience in crossing.
Alright so I thought about this some more. It seems that no matter if its a dipole or bipole you will still have a peak and null because of the summation from the waves between the front and back.
Its starting to look like dipoles are better off with active crossovers. I suppose if you crossover high enough to a woofer you could use a more simple crossover.
It would seem that a bipole can't kill baffle step. It might be possible though to put a dip where the natural baffle step peak is. Getting complicated.
Its starting to look like dipoles are better off with active crossovers. I suppose if you crossover high enough to a woofer you could use a more simple crossover.
It would seem that a bipole can't kill baffle step. It might be possible though to put a dip where the natural baffle step peak is. Getting complicated.
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Dipoles have quite a messy response due to the sound waves creating peaks and nulls. Of course this is only true below the baffle step. I assume bipoles have similar issues.
Linkwitz talks about it here Electro-acoustic models
I pity the fool who tries to flatten that with a passive crossover. Also part way down (A2) he says that dipoles have edge diffraction but even the great Linkwitz doesn't seem to know or care to explain why. Plain old box speakers are looking so simple now.
Linkwitz talks about it here Electro-acoustic models
I pity the fool who tries to flatten that with a passive crossover. Also part way down (A2) he says that dipoles have edge diffraction but even the great Linkwitz doesn't seem to know or care to explain why. Plain old box speakers are looking so simple now.
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With a bipole you get dips in response at the half wave distance and peaks at the 1 wave distance? It does look like the response is rippled but not exactly at multiples.
Why is the top end and bottom rolled off?
Do you like the sound? I am learning that I don't like the directivity change that happens in typical smallish box loud speakers. Dipoles and bipoles help with this.
Why is the top end and bottom rolled off?
Do you like the sound? I am learning that I don't like the directivity change that happens in typical smallish box loud speakers. Dipoles and bipoles help with this.
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Would you choose a rectangular enclosure as the default for the study of a bipole?
I think that's just free space. When you add the enclosure things get much more complicated since only some of the sound wraps around
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