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A visitor of my site sent me email with following:

“I take it you don't like the Rogero style (or Johan Dreyer) bass horns with wings, but you could add compression to a similar setup and make it work properly. I have made several designs with ….”

This idea of bass horn arrangement that those guys use is very interesting in context of this thread. Bothe Rogero’s system and Johan Dreyer’s were mentioned before and I the Johan Dreyer’s horns were discussed:

http://www.romythecat.com/Forums/ShowPost.aspx?postID=6605#6605

Johan Dreyer’s showed up occasionally at this site

http://www.romythecat.com/Search.aspx?Phrase=Dreyer

Both Rogero and Johan had the same type bass horn installation that is certainly very elegant and invisible. My major problem with this approach is that those have very large mouth and work at lower frequencies rather as direct radiators line-array then horns. In this configuration those guys shell not use 515G drivers but rather for 515B drivers that have always 25Hz lower resonant frequency. So, the idea of Rogero’s or Johan Dreyer’s approach is to put one ass on two chairs and to get lower bass from essentially midbass horns.  It would be very interesting to see the Rogero’s or Johan’s equalization curve. We need to subtract the room gain, then we need to measure the acoustic pressure with horn and without horn at 40Hz. (resonant frequency of 515G is about 37-40Hz). If with horn it will be 6dB or more then whatever I say of BS. I do not think it is. If you look at the picture of Johan Dreyer’s horn then you see that is it very large horn but short with relatively large throat.  This time of horn might be fully-horn loaded (have +6dB or more) only down to relatively high frequency. I see no way it will have horn loaded all the way down.

http://cgi.audioasylum.com/systems/8608.html

It is not the way how I would like to go with my own solution. I would like my midbass to have resonant frequency around 45Hz, the mouth rate to be around the same and the horn do not out (anechoicly) anything under the mouth rate. In this case the mouth will take care of the throat reactance and the driver will be properly operating on its own merit with no excessive excursion and with fully loading the horn down to the lowers horn band-pass frequency. So, I would like the lowest octave of the horn to be the effort of horn, not the horn’s driver. Sure the total sound in the room will be less extended to the bottom but it will be much cleaner, much SOFTER (which is the key) and will never sound like elephant belch – the characteristic that 95% of all midbass horns sound out there.  I do not propose that it is how the Rogero or Johan bass horn sound. I never heard them but anyone understand that all those conservations are purely speculative and all that I am trying to do is to furnish (based up my other experiences) the best conditions that might (or might not) lead to superior/maximum result for chosen topology.

So, would it be possible to optimize the Rogero’s and Johan’s idea to make it suitable with my objectives. I think it is and I think it might be an interesting direction as well. If to make the horn like Johan Dreyer did only to drive it with a single 8” throat then the horn will be longer but it will be properly loaded. In this configuration the curve will not be only on right and left but also atop and at bottom. Sure, I would like to use only long walls for my playback, so I was playing with the Rogero’s and Johan’s idea true to do it effective, elegant and small. Below is what I come up with. An additional good part for this idea is that it has no extended attributes outside of building and it will not have any zoning problems or the need to have neighbor compliance.

Also below is my sketch of a “perfect room” (in terms of dimensions) I posted a week ago in other thread.

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