Speakers for a very large room?


Reader of posts for a few years but have not posted a serious question until now. Currently have McIntosh integrated tube amp with some old KEF speakers. While I enjoy it in my current setting, I am moving to a house where my listening room will be 30' x 40' x 10'. It has polished concrete floors. Sounds like a grocery store but it is not. I suspect I will need to change speakers but really have no clue where to start. I listen mostly to progressive rock but also anything in the same general area. I don't know where to start with such a room? I am at least 3 hours from any major city. I did experience Treo CTs once and to bright for my ears and Wilsons but did not care for the visual appearance though liked the sound better. It was a few years ago so can't better define what I liked.  Not a great resume of listening experience but it is what it is at this point. For some reason, which may be completely wrong, I am thinking electrostatic may work well in this setting. I could easily move them 5 feet out from the back wall but then again I really don't know what I am talking about. Any kind comments would be appreciated.

Rich
ricmci
Large room, rock, tubes = Klipschorns

Had them for over 25 years in a large(ish) room and loved them. Of coarse you would need 2 corners for them. You can probably get them used in near perfect condition in you price range. They come around every so often.
I too have a large room.  The best thing I did was to get rugs.  You'll be amazed how that large space will just eat up the sound and be disappointing.  It took me a long time to get it even approaching right.  Take your time.   If it were me, I'd put in large Tannoys, but that may be out of your budget for now.
I'm glad Stanley (Stringreen), mentioned Tannoy. In my room (16.5' W X 34' L w/cathedral ceilings), my custom built Tannoy 12" HPD's (they also come in 15"), work great in my large room, with no room treatments, though my carpeted wood floors play a significant part in taming room issues.

I couldn't afford anything new, so I bought vintage ca 1975 drivers and had massive 150 liter bass-reflex enclosures made for them. 2009 prices, it was around $5000. I don't know that I would trade them for anything. Horn speakers are an attractive alternative, though the upper mids and treble frequencies in the HPD's are handled with  concentric horn tweeters. Ebay UK is the best place to find them, I've found.

Hope you find the exact right thing for you, and your SO. Regards,
Dan
Thanks you all for the responses.  I will definitely look into the Tannoys.  Never thought about horns but will research.  I am not sure I have very many options other than to make the large room work.  System certainly not going in the master bedroom.  Other smaller room will be a bedroom and the other will be a gym.  Smaller detached carriage house would be perfect but then not ideal for entertaining guests or having my family enjoy it.  I am going to get it set up and see what needs improving.  I suspect first thing will be consideration of some room treatments as suggested by many of you.  

Thanks, Rich