Open Baffle Terminology?

I had always understood the baffle to be the mounting for a speaker designed to prevent rear radiation from cancelling front radiation. Practical limitations, i.e. length of the lowest frequency wave of interest, usually argues for some sort of enclosure rather than a huge mounting surface. Do people really mean an enclosure with an open back when they refer to an open baffle? I've seen this now several time on Audiogon. One 'goner emailed photos of his elaborate "open baffle" construction, and indeed the speakers were mounted in baffles that forms a sort of wing open to the back. Such a design may give great dispersion through reflection, but LF response would seem limited.

'Open baffle' means 'not closed'. The baffle may be a narrow plate (of MDF of other wood) just large enough to hold the drivers, or it may be somewhat elaborate, as my angled-back wings attached to 11"-wide frontplates are. But the defining principle is 'not closed'.

The other day I saw a system composed of a half-dozen 6X9s with a tweeter between the 3rd and 4th drivers...I guess it was a hybrid of line-array and MTM principles...with no baffle or plate whatever; the 7 drivers were fastened to 4 vertical rods. Unfortunately this system sounded very thin in the lower frequencies and required lots of support in the lower-midrange and bass via 2 powered woofers; it sounded anything but coherent.

You're certainly correct that the slimmer the baffle, the more the lower frequencies generated by the drivers are lost to wrap-around cancellation.

AudioCircles has an Open-Baffle Forum... . You might look around there and see what others have done.

I think I sent you pics of my system; the next (= 3rd AND LAST!) version of the baffles will be much narrower overall, which will require more equalization to flatten the response and create the tonality I want.

I read a number of the posts at the link you kindly provided, but came away with no understanding of the acoustic principles these designs are aimed at. Some of the cabinet bashing seems simple ignorance of acoustics. But at least I now understand that open baffle means parts of the enclosure are absent, not that the baffle itself is open in the general case. Of course, any of us who have played with speakers or considered their physics knows they can be operated without a baffle, but the frequency range will be attenuated by cancellation.

Study this guy's site for awhile. You need to eq to compensate for the low frequency losses, so you need lots of good quality displacement. In return you get freedom from many of the room modes that play havoc with your system's bass in the time domain.
A OB can be just a board with driver and nothings wrong at all with this design except large size for best bass.To keep this siple.A OB keeps back out of phase wave from canceling front in phase wave this is why many drivers like woofers etc need cabinets in the 1st place.