Big, big room -- which 10-20k speakers?

I think by this time we are seeing what some of the issues are with filling a large room. Nearly everyone who mentions a speaker with lower efficiencies is also recommending a subwoofer and quite often some very powerful amplifiers.

The problem with this is always blend, and system complexity rarely contributes to musicality.

This is why I recommended the Classic Audio Loudspeaker. Fist off, you won't need a sub. The T3 has dual 15" woofers, one down-firing and the other forward firing. With 98 db efficiency, you will be able to operate a tube amp with only 60 watts and do nicely filling the space.

The problem here is that you can count the number of 500+ watt amps on one hand (with fingers left over) that sound like anything close to real music!

So if you have a speaker of higher efficiency you have a much wider range of amplifiers available!

A few years ago we set up a system at RMAF, in the biggest room (A ballroom) available at the show. I think the room was a good 120 feet long, and at least 60 feet wide. We had no trouble filling it with power to spare using a set of Classic Audio Loudspeakers and a set of Atma-Sphere MA-1s. For the most part the amps were loafing. That is how you want the system to work. If you are pushing it hard all the time there is no way its also going to be sounding its best.

+1 Atmasphere..

Exact same reasons I named big Tannoys.

Avoiding complication to system, and staying within stated budget (used).

I agree with a horn speaker system or large Tannoys. Another possibility is the Jamo R909 that is moderately efficient. I know it needs a big room and would benefit with more power and current, but you probably could get by with the Luxman depending on your listening habits.

"So if you have a speaker of higher efficiency you have a much wider range of amplifiers available! "

That may be true but you only need one and there are plenty to choose from.

There are many ways to tackle the problem effectively.

High efficiency is likley part of the solution somewhere, be it more efficient amps capable of delivering more power in a smaller more efficient package, higher efficiency speakers that require less power to sing, or perhaps even both together, or some middle ground even perhaps.

Lots of ways to skin the cat.

Tannoys and Classic Audio are certainly good contenders, but the there are many possible ways to skin this cat, including use of power subs, especially when already integrated into the speaker design by teh vendor, though adding separate subs can work very well also.

I used to work at a dealer that sold Revel, Wilson Audio, Avalon, Avantgarde, Joseph Audio, and Ariel. I am now a composer and recording engineer. My advice is to buy speakers that are meant to fill a large space. I would look at the Klipsch Pro Cinema speakers first. Other options are vintage Altec Lansing (or new Great Plains Audio), or a custom/DIY horn hybrid. Most audiophile/consumer speakers are terrible with a large space. You might check out ALK Engineering, Crites Speakers, or Volti Audio for semi-custom solutions. Classic Audio Loudspeakers are great if you can afford to go that way. The Luxman rep. has a pair. Good luck.