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

OHM F 5015's with 15" powered subs built in for ~$10,000 (if available currently) can fill that room as good as just about anything dsigned for home use, I would bet. The powered subs would take a lot of load off the main Luxman amp and could work very well I am thinking.

My OHM F5s which are similar but without powered subs running off my $3600 used BEl Canto ref1000m 500w/ch amps could even do a respectable job I bet. This combo has yet to show any signs of stress or breakup at any volume in my setup. The wide range OHM CLS Walsh driver that handles most music up to ~7Khz or so and minimizes demand on the tweeter is a big reason for that. Few other speaker designs can compare in terms of ability to go loud and clear, perhaps none at similar cost.

Older earlier generation OHM Walsh 4s or 5s might be had for less than $1000 used. I have used old OHM Walsh 2s outdoors even off an 80w/ch Tandberg receiver, and volume was never an issue. It sounded as much like live music as most anything I have ever heard, including many big buck reference systems. The sound of the older model OHM Walsh speakers are not as refined overall in most rooms as the latest and greatest, but might work very well for very little if room size and acoustics becomes the bottleneck towards achieving the kind of high end audiophile sound one might expect in most rooms.

Pro gear is more often applied in very large rooms/venues. Not as sexy, but perhaps the most bang per buck?

In addition to the other suggestions, if you can find them, Duntech Sovereigns or Dunlavy SC Vs or VIs could give you that big sound, but I doubt that the Luxman would be up to driving them to best effect in that big a room (especially the Sovereigns which, despite their relatively decent stated efficiency, really need an amp that can control their low frequency drivers).

If you really want to fill the room with your current equipment, I think Atmasphere's advice is the best; or else you can just use part of the room in a more nearfield setup as others have suggested, that would give you far more options. The glass walls will be an acoustic problem for you, I'm sure.

I'd say pick up a pair of old OHM Walsh 5s somewhere for <$1000 and give those a shot first before spending big bucks. You'd have little to loose and much to save/gain even if they do not cut it. They can be resold easily with little or no loss,or traded in to OHM for up to 40% discount on a newer pair if desired.

I would love to have a room that size for any OHMs and would never trade it if I did for anything in the smaller rooms most of us are limited to in our homes. I've found the OHm Walsh CLS speakers are NEVER the bottleneck. In your case, the amp would be, but it may still be good enough that it not matter. MAxing out the amp with the OHMs in a room that size should be an incredible experience that I would love to hear! That or the option of adding a good powered sub.

[url=http://www.stereophile.com/floorloudspeakers/687ohm/]1987 Stereophile Review of the OHM Walsh 5[/url]

Another good candidate to look at would be Tannoy larger Prestige line. Probably Westminster or better still the Westminster Royal SE. Had them for years in a room almost as large, driven by Cary 300SE (15w), then later Cary CAD805 (50w), filled the room sweetly without a sweat. Your Luxman will be more than up to task, I'm sure.

At one point, a friend looking to buy these speakers demoed them at my home and brought his Accuphase (less than) 100w integrated+Sony 555ES cdp if I recalled correctly, it sounded great too that he ended up with the Canterbury (one model down). Definitely worth to check out ie.if you don't mind/love their classic look.

All this talk about what speaker will fill what room, with not much mention about how it's going to sound in the end. You should allot 1/3 of your speaker budget towards room treatment. You are going to need a lot of it.

Shakey