Hi Hotmailjbc,
you have two very good recommendations here, the Orion and several designs by GR Research. Nice thing about many of the GR designs is that they incorporate a 12" sub into the cabinet, but the separate sub is always an option. These may or may not be a challenging build depending on one's abilities. And there are simpler approaches if you just want to experiment. Or, another option is to contact one of the builders of these speakers and contract a pair.
The open baffle designs can give you presentation close to the electrostatic/planar. They image very well, sometimes in circumstances that would destroy the presentation of most other designs. They can also have dynamics that approach that of horns. OB designs are usually pretty efficient also. Most speakers of this design don't give the "audiophile" presentation many folks get wobbly in the knees over, but that is a good thing IMO.
Personally I would avoid single driver, full-range designs. (Except again for experimentation.) Unless one can afford really expensive FR drivers there will be response compromises. I know for myself that would just lead to my adding drivers and more xover parts to fill in the frequencies.
I am very familiar with the OB-7 from GR Research since I can hear these from my neighbor's house, 100 yards away. ;-) I arranged the purchase of these speakers for this neighbor who was buying solely on my recommendation of Danny's work at GR. Long story short, my neighbor has been rocking the neighborhood for three years now, and still raves about the OB-7s every time I visit. He says he gets compliments all the time from people who stop what they are doing for a minute or so to listen.
