Apologies, that was indeed an unclear term. The control that I personally miss most (with OBs) is over their rear radiation, for two reasons. Firstly, I find that the default OB radiation pattern can be unsuited for placement close to rear walls or furniture (which is often unavoidable in small rooms); at best the sense of (what I'm calling) OB spaceousness becomes somewhat compromised, at worst it is replaced with smearing as the rear reflections start to occur too early. Secondly I don't personally find that the spaceous effect is wanted/suited to the same degree for all kinds of music that I want to play. There are 'some' things one can do to control the direction and magnitude of the rear radiation, but I haven't been truly successful yet and it is especially hard to tweak to taste between different recordings.
You asked for an example of a design which IMO has more such control; my personal preference would be something like a unity/synergy/multiple-entry horn (or a horn+bass-diver like the Gedlee summas). These too control sidewards radiation patterns and reduce unwanted early reflections, similar to OB (arguably with even more control). By default they also control the rear radiation so much that there is possibly too little for some people, which at least makes positioning less fussy but wouldn't satisfy a lot of OB fans. But of course (if wished) people have successfully then added rear-firing drivers/tweeters to a variety of speaker designs for a very similar effect, which can then be much more easily and finely adjusted to one's own situation and taste, even on the fly if using an active approach. Then there are additional possibilities like introducing and controlling rear-firing delay if using DSP etc., or one can use DSP to control things like the apparent soundstage without rear-firing drivers.
Of course very different levels of complexity and not for everyone; the minimalism of OB and visual elegance of some designs are very appealing indeed. Conversely big horns with complex driver arrangements are very different to design, and end up often just as wide but also deeper. Although it is the route that I'm personally starting to take because I think the effort will be worthwhile for my situation; it may be different if I had room(s) large enough to give OBs the space they really deserve to work optimally, and if I listened mostly to live recordings or similar.
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No matter how well you design and construct a speaker cabinet, some degree of "boxy" sound will always remain. This is due to several factors:
First, the way sound radiates off-axis changes significantly with frequency. This alone contributes to a characteristic "box" sound that cannot be eliminated simply by adding damping or reinforcing the cabinet.
Second, internal air volume resonances tend to be more pronounced than cabinet panel resonances. Damping materials help but are highly frequency-dependent, meaning they cannot eliminate all resonances evenly. Overdamping can even make a speaker sound more constrained and unnatural.
Third, the thinnest and most acoustically transparent "wall" in the cabinet is actually the driver’s cone. At certain frequencies, speaker cones allow sound energy to pass through, interacting with internal reflections and adding to the "boxy" character.
Even extreme cabinet designs—such as solid aluminum, concrete, or constrained-layer constructions with matrix reinforcement—still exhibit a "boxy" signature. In contrast, loudspeakers that minimize or avoid enclosure coloration, such as open-baffle/dipole designs, full-range cardioid systems, or full-range horn speakers, tend to have a more natural, less "boxy" sound due to their more consistent directivity patterns.
I've been tinkering with OB several years now, and I think I'm settled on my design now. Recently I noticed my Amazon Music app now includes its version of room eq.
It tried it out on a 0.75ft3 2 way I made some years ago, and without eq it measured +/- 1.5db 100hz to 15000 hz, with auto Eq, it gets a narrow Q 12db dip at 92hz, and the rest looks left alone.
My OBs sound nearly identical to me after fine tuning each crossover to my room, with added spaciousness, excepting my adding a mild dip first order centred at 4000hz.
With auto eq, the result sounds hideous. A 9-12db boost from 32hz to 1500 hz, a 7db cut from 1900 to 2200 hz, and a very narrow spike at 4100hz.
Needless to say, but I'll say it anyways- I threw out the room correction suggestions, aside from a cut at 92hz, which I steepened and reduced to 7db.
Would this just be a function of a terribly mismatched phone mic the app uses, or does dipole measure differently than a ported cabinet?
Both were measured 14 feet away, with the mic pointed at the centre between the speakers, midrange height.
Of course it's going to measure differently, because of how it interacts with the room. As I mentioned before, P-wave bass can literally roll across the countryside (I've heard it outdoors and was unable to locate the source direction; someone playing something BIG outside in the vicinity) while let's call it "S-wave" bass from an OB is gone after any distance. OBs are very forgiving to the neighbors that way.
Perhaps Amzn's design of the app expected enclosures in a room, which 99% of their customers probably have. Not a great explanation I know, but cant think of anything else!
Thanks. The huge but relatively flat room correction boost from 30hz to 1500 hz was ridiculous sounding to me, especially given the 900hz first crossover point I used, a 7db what looked like a 10Q spike at 4Khz was expected, given I've always preferred a dip there in my own speakers.