Which speakers will fill 5,000 cubic ft coherently

Appropos your comments about Ralph, Tvad, I have spoken to him today and he confirms his generalisation that 8 ohm impedances are better for all tube amps; however, he believes that he should re-state his assertion, since it is taken too literally (I don't want to put words in his mouth and maybe he will chime in here) - he believes the MA-2 can easily drive the Tyler Woodmere, with its benign impedance curve, but states that it would sound even better with an 8 ohm, rather than 4 ohm, impedance. So that doesn't disqualify a 4 ohm speaker for mating with the MA-2, since the speaker's 91 db sensitivity will compensate somewhat. But the Woodmere doesn't have a 60 day trial like the Zu Definition, so a trial could be "hazardous", and I've done that once already..........I suppose to get as close to "perfection", all the known criteria should ideally be met, and a higher impedance than 6 ohms is one of them, so your point is valid.

>>3-19-08 Tvad: I'm interested to know how you or Ralph are determining that the Woodmere speakers have a benign impedance curve since the minimum impedance spec of the Woodmere is not published on the Tyler webpage. Ty only publishes the nominal impedance spec.<<

Based on Ty telling me it is an easy load and drops to low-mid 3's.

I'm not arguing about any of your points, tvad, just reporting what Ralph said based on Ty's conversation and Ralph's knowledge of the speakers.

What this implies, if taken literally, is that no 4 ohm speaker should be driven by a tube amp. Period. I'd be interested to know how many audiophiles follow this rule. Anybody out there drive a Woodmere with any tube amp?
Does thais imply that all speakers with 4 ohm impedances are ruling out tube amps to drive them? I'd be interested to hear other speaker manufacturers' comments.

Read my post carefully. I conceded that it would/could be a mis-match.

So now I am looking at speakers that look great (WAF), have a small footprint, have 13 0hm impedance and can stand 6-12" from the wall - Selah Audio Alexandrite. Long build-time, but who's in a rush? Any comments?

Tube amps employ an output transformer to match the high output impedance of their tubes to the lower input impedance of the speakers being used. These amplifiers have at least two separate binding posts for (usually) 4 or 8 ohms depending on the number of windings in the transformer being used at that impedance.
OTL (OutputTransformerLess)amplifiers do not have output transformers to adapt them to low impedance speakers. Sometimes an outboard transformer like the Speltz is used to compensate for a native mismatch but, as I stated earlier, that rather defeats the purpose of having an OTL.

Regardless of claims to the contrary, you will always get better results by optimizing component matching. OTL amps are better matched with HIGH impedance speakers. This does not mean that other speakers will not work but it does mean that they will not be ideal mates for your amplifiers.