Which speakers will fill 5,000 cubic ft coherently

Ralph's advice about no less than 6 ohms and preferably not less than 8 ohms is right.

I've tried the Speltz autoformer. Although I really like the speltz cables, I do not recommend the autoformer. I've tried it. I believe it exists as a band-aid for those who have an amp/speaker mismatch and it may be helpful in that context. It does, however, introduce problems of its own. IMHO, a seller who recommends buying a 4ohm speaker and the autoformer to go with the Atma is doing a disservice.

Again, with a room that large, why are you limited to a 10" speaker width? Maybe I am misunderstanding the situation, but any of these speakers need breathing room around them and you have a big room.

Using outboard transformers with OTL amplifiers rather defeats the purpose. Appropriate speaker matching will make more sense and bring better results. Also must agree with Shadorne about cramming high performance speakers into too small a space. This will waste your money.
Most manufacturers are becoming very desperate for sales. Be sure to verify what they claim about their products.
I had Definitions and they are almost 12.5 inches across the front. I now have Presence which have a 14 inch baffle width.

My question for you is: If your room is so large, why must you squueze your speakers into a narrow space?

For what it's worth, the last I heard, Ralph himself was using Zu Druids.

>>3-17-08 Macrojack
My question for you is: If your room is so large, why must you squeeze your speakers into a narrow space?<<
Do you really need to know the geography of my living room? Surely it would bore you??? Take it from me, I have no more than 18". If I knew how to post a photo, I would.

>>05-21-07: Atmasphere
Anytime you are investing in tube amplifier technology, that investment will be best served by a speaker that is at least 8 ohms or more.

Tube amps, with rare exception, have reduced performance into four ohms.<<

So that makes the Defintion AFI the best choice, (30 ohm impedance) particularly since there is a 60 day in-home trial. Can anybody tell me why there are such divided camps on the Definition? I have read about the "Zu sound". Anybody expand on that?
And them, of course, I have to sell the Kharmas - not an easy job in today's economy.

To take a step back for a second, you're more likely to have success if you first match the speakers to the room and then match an amplifier to the speakers. You seem to be trying to collapse these two separate steps into one. Not that it can't be done, but it greatly limits your options. In other words, why are you so tied to your amp?

If the emphasis is on coherent sound you might also consider the larger coaxial designs from Altec (Great Plains Audio), the big classic styled Tannoys or the various Phy based speakers. They are all very efficient and like tubes.