Planar close to a rear wall? Quad for example?

I have to agree- Dipolar radiators just DO NOT do well close to the rear wall.

If you can completely absorb the backwave, it would probably work. Unfortunately I don't think that's realistically possible. The problem is, the two-foot round-trip path length difference (imparting a 2-millisecond delay) before the backwave energy arrives at the listening position puts it right smack in the time zone where the ear is most sensitive to coloration and loss of clarity from reflections. On the other hand, 10 milliseconds of time delay (corresponding to Sogood51's five-feet-out dipole speaker positioning) is long enough that the reflections will add richness and liveliness with minimal detriment.

I build monopole and bipole versions of essentially the same speaker. If I had a customer with the same positioning constraints you have, I'd advise him to go with the monopole version. That would be my advice to you DrKen - go with a monopole speaker for now. I don't think Quads or other dipoles are going to work well for you.

Duke
dealer/manufacturer

You might want to consider Gradient Revolutions. They are designed to work very well when placed close to the rear wall. More than one reviewer has likened their sound to Quads. They do, however, require large amounts of high current power.

I heartily endorse Onhwy61's recommendation. I've only heard the Revolutions at shows (CES several times), but in every instance, the Gradient sounded terrific in small rooms and backed up to the wall. It is specifically designed to accomodate difficult placement and is very flexible in the way it can be configured. A good looking, good sounding, and easy to place speaker. Downside? It is not terribly efficient, but then again, if it is placed in smaller rooms, a lot of power will not be needed.

a number of years ago, i visited a technician who repairs quads. as i walked into his house, i noticed a pair of quads
set up in his kitchgen. the speakers were very close to the wall, probably, no more than 1 foot.

while there was a loss of depth, the naturalness of timbre was evident.
a poorly set up pair of quad 57 is preferable, to my ears, to any cone design.

hi duke: why don't you design a pair of electrostatic speakers to compete with the sound labs you sell ?