Ripole with two 10" drivers?

Having just bought a pair of Quad 2805s (one faulty, but being fixed) and remembering Jazzman's diy 'statics with ripole subs, I wonder if I can get away with a pair of Peerless SLS 263 10" subwoofers. The specs are very similar to the 12" SLS, but with reduced cone area and therefore output, but I have so little space available, 10" drivers might make it possible where 12" wouldn't.*
I am not looking for loud, just a bit of clean extension. I also have an analogue active crossover (Ben Duncan design from 1982, upgraded since), so I could use a second amp for them, and cut off the low bass from the 2805s. A pair of 10" ripoles would be hideable (from the wife, as much as anything; if they don't intrude they would be acceptable. I don't know how I've managed to sneak in the 2805s! :))
Any advice welcomed, as I am unsure how to calculate the cabinets too.
* One may have to go under an open framed sofa.
 
I built a pair of Ripoles using a pair of 12" Infinity Reference RF1200S low-profile subs in each cabinet to go with my Magnepan speakers. I couldn't be happier with the results. After room EQ the frequency response is flat down to 27Hz.

I had a little trouble calculating the size of each cabinet due to confusion about the math as explained by JM in his write up. The problem was with calculating the area of the center chamber opening. I figured out that the calculations for the center chamber need to be calculated by doubling the amount of cone surface area since there are two subs firing into the center chamber.

Here are pix of the subs. The enclosures only measure 13.5" wide by 15" deep and 16" tall. I used 3/4" MDF for the cabs and wrapped them in oak veneer. They're pretty compact when you consider there are two 12" drivers inside. I didn't care for the magnets hanging out the sides of the cabinets like JM's subs. That's why I decided to go with the lo-pro Infinity subs.
 

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I'd just like to add that I've owned my Maggies since '91 and in that time I've built both sealed and vented subs. I even built a transmission line sub to go with the Maggies. While they all added low end in the end they just weren't satisfying. They just didn't blend together nearly as well as the Ripole subs. Magnepan recommends using a dipole sub design with their speakers. I've been listening to the Ripoles for a few months now and I must say that I agree 100% with that recommendation

Here's the frequency response of the subs and my Maggies after running my MiniDSP DDRC24 room correction equalization. I tweaked the treble up a bit to offset my now 60 year old hearing.
 

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ripoles have very uneven response, they need to be equed to fit the bill
how do you plan to do that awkwardbydesign? passive? dsp?
It would be either passive, or within my analogue active crossover. I have no wish to use digital in the audio chain beyond the DAC. If I use the Ripole only at the very bottom I would hope to minimise any equalisation. But it's all new at the moment, so all advice and suggestions welcome.
 
I'm not sure it's modellable? This from the link I posted is questionable

"A Ripole is basically a compact, folded-baffle dipole. It can play very low, and because it projects a “figure-eight” sound pattern that nulls the output off-axis, it excites fewer of the room resonances that can give bass the dreaded “one-note boom”. Ripoles are clean and musical but, being dipoles, they can’t pressurize a room with the kind of chest-thumping bass that many prefer for HT sound effects. I would say that Ripols are great for music, especially jazz, but not so much for theater earthquake effects."

They are probably more cardioid than dipole, and I don't know what he means about the pressurizing the room bit, that is oft repeated
 
Perhaps I should also have added "calculating". That quote is one of the things that piqued my interest, plus Jazzman's build, which I saw quite a while ago. But building the 'statics was a bridge too far. Perhaps when I was younger.
I think the pressurising bit refers to the fact that a monopole sub will add pressure in sealed room, whereas a dipole can't, as any pressure increase from front radiating will be cancelled by rear radiation.
 
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I think the pressurising bit refers to the fact that a monopole sub will add pressure in sealed room, whereas a dipole can't, as any pressure increase from front radiating will be cancelled by rear radiation.
That's probably what people think, but if that does happen (how many people use a sealed room?) it's only whilst the cone is moving outwards. What we hear is SPL, it's just requires more work from a dipole than a monopole.
 
I'm not sure it's modellable? This from the link I posted is questionable

"A Ripole is basically a compact, folded-baffle dipole. It can play very low, and because it projects a “figure-eight” sound pattern that nulls the output off-axis, it excites fewer of the room resonances that can give bass the dreaded “one-note boom”. Ripoles are clean and musical but, being dipoles, they can’t pressurize a room with the kind of chest-thumping bass that many prefer for HT sound effects. I would say that Ripols are great for music, especially jazz, but not so much for theater earthquake effects."

They are probably more cardioid than dipole, and I don't know what he means about the pressurizing the room bit, that is oft repeated

You guys need to check out the Tactical Response (BOSS) threads on avsforum.com. Guys are bolting cheap 12" JBL G series car audio subs to their recliners and couches. Search Nalleh. He has a crazy Dolby Atmos setup along with ridiculous TR updates and measurements.