Room treatment advice

I have a fairly difficult room to work with, and I was wondering what advice you all might have for me. It is a medium small room, with a large sliding glass door on one wall (which leads to a 3 seasons room). We will call this the "right" wall, as you are facing the main speakers. The rear "wall" is mostly an open passage to the kitchen. I do have high ceilings (14' or so), so there is a wall higher up, but the passage opening is doorway height. The left corner of the real wall is a large fireplace, with stone from floor to ceiling. The left wall runs about 10 feet, and then opens into a hall way. The front wall (which is where my stereo/HT setup resides) also opens into a hallway just to the left of the system.

I have Thiel CS3.6's placed about 1' out from the wall. On the left side, they have plenty of air. On the right side, they are about 3.5' away from the wall. This setup is esthetically accurate, and the imaging works out quite well from my primary listening position. I do not currently have a sub, but I am considering one. The center channel (Thiel SCS3) is on top of the TV and works well there. The surrounds are on wall mounts along the top of the rear wall (and above the opening to the kitchen).

My main problem is that this room has very little bass reinforcement. The mids and highs are fine, but the low end has a lot of opportunities to dissipate. Adding a sub should help, but I have read so much about rooms and room treatments, that I am wondering if there are other tricks and techniques that I should be considering.

Thanks in advance, Tom.
Hi Tom...You aren't kidding, that IS a difficult room. IF I understand your description correctly, it is almost an "infinite baffle" situation with reflective areas scattered around. I'm no expert, but I'll give it a shot.

You mentioned that mids and highs are fine, but you may want to try covering the glass doors on the right wall and the upper part of the stone fireplace as a trial, with a towel or blanket. This would sort of make the room "infinite" all around. Sometimes, with those frequencies, just keeping the levels approximately even from all sides is enough to make a noticable improvement. Also, if possible, I would move your main speakers out into the room (away from the wall behind them). Neither of these things has specifically to do with bass response, but you may be surprised with the improvements.

Now for bass response, I'm a BIG fan of twin the point that, lately, I would rather have no sub at all than to only have one. Although I've never had such an open space to play with, a room like yours may be a good place to try corner placement of two subs. In most rooms, I would only recommend this for HT and never for music, where I would suggest to pull them out in the same plane as the main speakers with unequal distances from the side walls. You lose some reinforcement this way, but the sound is much sharper. However, in a space as open as yours, the extra reinforcement may be a good thing. The good news is that, even with very cheap subs, you can hear the improvement from one sub to two...Soooo, go borrow the subs from two friends with HT-in-a-box systems, play around with one versus two and various positions to determine which setup gives you enough oomph, then go buy the best sub or subs you can afford to get the boom/bloat out and the crisp punch back in. Hope that helps.
Yes, thank you for the response, Goinbroke (great name!). Interesting point about keeping the levels approximately the same from all sides. I may not be able to completely solve that problem, but you have given me some ideas. In addition, I have, indeed, been fretting over the one sub or two quandray. I want to make sure that I get a good quality sub, that is both musical and fast. I hate the boomy, no definition bass thing. Perhaps it's because of how ridiculous I think those Honda Civics with a trunk full of low quality subs sound when they come booming down the street. To that end, my front runners are either something from REL or one of Velodyne's new Digital Drive subs. I'd love to get a Thiel SW1, but there is no way that I could afford two of them.

Thanks for the help, Tom.