Mains for the Dr. Geddes Multiple subwoofer system

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Recently I went for the Dr. Geddes approach of aplying multiple subwoofers to get a really flat bass response in my small room, and it's really awesome what this can do.
Them I came with other problem, after placing 3 subs is my small room, my main speakers are just too big for my space, they are 220 liters each :)
So I'm planning to build a 3-way or 2-way speaker that does not need to go low because I already have the 3 subs, 50hz is a good starting point for the lows.
The crossover is not a problem because I will go for an activeone, so the main concearn is the drivers choice and type of enclosure, sealed or ported, 2 or 3 way... I really have no idea where to start, I only now that it has to be small, at most 50 liters each. Any idea?
 
1) You are correct in selecting a 50Hz Xover between your mains and the Geddes woofer swarm. There are several well reviewed papers with data showing that most ears can detect the physical location of a bass tone higher than 60Hz.

2) Most High Quality main speakers with a 50Hz bass are larger then 50l.

3) If you like the sound and polar response of your current speakers you could paint them basic black ... it is very slimming :) OR you could reuse the speakers with a smaller cabinet design. Maybe less efficient. Maybe requiring more active bass boost. Maybe using newer engineering ideas. Maybe you can live with a TALL small footprint cabinet, or a fat-bottom with narrow top cabinet.

3b) If you describe your current speakers, you may get useful engineering ideas for a high quality "smaller but still larger than 50l" design.

You know: Reduce --> Reuse --> Recycle
 
1) You are correct in selecting a 50Hz Xover between your mains and the Geddes woofer swarm. There are several well reviewed papers with data showing that most ears can detect the physical location of a bass tone higher than 60Hz.

Which papers?
60Hz has a wavelength of 5.73m, 80Hz is 4.3m. The directional features people hear are probably simply caused by modal pressure gradients. There is no real localization of a low frequency source in acoustically small rooms.
 
Recently I went for the Dr. Geddes approach of aplying multiple subwoofers to get a really flat bass response in my small room, and it's really awesome what this can do.
Them I came with other problem, after placing 3 subs is my small room, my main speakers are just too big for my space, they are 220 liters each :)
So I'm planning to build a 3-way or 2-way speaker that does not need to go low because I already have the 3 subs, 50hz is a good starting point for the lows.
The crossover is not a problem because I will go for an activeone, so the main concearn is the drivers choice and type of enclosure, sealed or ported, 2 or 3 way... I really have no idea where to start, I only now that it has to be small, at most 50 liters each. Any idea?

I'm in the same predicament.

I used to live in a humongous house in the middle of nowhere, and at one point I had ten subwoofers and a pair of Gedlee Summas.

Ten subs sounded noticeably better than three subs, but the room just looked like hell. So I whittled it down to three subs, and the Summas.

After a while I got sick of the third sub, which was bigger than a refrigerator, and replaced it with a smaller sub.

Then I moved into a new home, with a living room that was way too small to accomodate the Summas.

I currently have a five way set up with plain ol' Kef UNI-q satellites, and three powered subs.

Those UNI-Qs sound surprisingly good. For instance, I've been running a set of JBL Prosound speakers, with a very nice waveguide, for the past two weeks. The only reason I have the JBLs set up is because I am selling them on Craigslist. While the JBLs have a better midrange than the Kef, I'd say the Kef high frequencies are much "cleaner". Even my girlfriend commented that the JBL is a little harsh on the top end, and she's no 'audiophile.'

Obviously, take this with a grain of salt - I haven't measured the JBLs, and it's very likely that the equalization that I'm applying to counteract the 'droop' that's caused by constant directivity waveguides isn't 'dialed in' properly.

But, the bottom line:

Kefs work pretty darn nice. And they're cheap. Having said that, the dynamics that you get with a big midrange cone are compelling. I've always said that if I had to do it all over again I would've gone with the Abbey over the Summa, due to it's smaller size. But perhaps I could even be happy with the diminutive Nathan speaker.

And, as always, IF YOU HAVE THE ROOM the Summas are lovely.
 
not yet cause I added another sub, a 15 inch dayton with a 80 liters sealed box, actually, my sub config is with 4 units not 3.
Sub 1 = dayton 10 inch sealed 30L
Sub 2 = SVS sb-12nd 12 inch
Sub 3 = dayton 10 inch sealed 30L
Sub 4 = dayton 15 inch ST385 II

Captura de Tela 2013-05-11 às 16.53.44.png
 
1) You are correct in selecting a 50Hz Xover b
3b) If you describe your current speakers, you may get useful engineering ideas for a high quality "smaller but still larger than 50l" design.

You know: Reduce --> Reuse --> Recycle

My mains are a JBL L300 clone, with a difference that the mids and tw are ScanSpeak, 8545 and 6600 illuminator.
Of course I could use the SS drivers in a project... As the bass concearn is not important, maybe a sealed project with these drivers could work, but I'am afraid that the low-mid quality that I am hearing from the JBL 15 inch drivers be lost. The Xover is at 200Hz so the 50~200Hz region is my achilles heel.
http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=39434&d=1243099331
 

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