one or two Sub-woofers?

I agree that one great sub is better than two not so great ones. But two great ones (stereo subs) is the way to go if you can afford it. So if you're on a budget, I agree to get one now and save up for the second one. For your speakers consider the REL Stadium III or even better a Stentor III.

My advice is to go with the 2 Lunas. As pointed out by others, two subs are definitely better than one. The Luna is a high quality unit. It won't go as low nor will it go as loud as the Rhea, but in a moderate size room at reasonable volumes, these points shouldn't be an issue. It's not that I disagree with Perfectimage or Sugarbrie, but their suggestions will double your budget.

I too have CLS. I have a pair of home-built subs, using NHT1259 drivers in approx 2.8 cu. ft. enclosures. 2 is definitely better than one. If you have the time, inclination and skills, it's not hard to build better-quality subs than what you can buy commercially for anywhere near the same $. These two subs cost probably less than $600 for materials. Sure, you need an amp and crossover, but those are items you may have already (I did), and having them separate gives you more flexibility for future upgrades. I am more than happy with the way they worked out in my system, though I've been considering the Stryke HE-15 sub(s) as a possible upgrade/replacement. (www.stryke.com). Not like I need to replace these, but the Stryke driver just looks soooooooo nice.... ;-)

have fun,
-Ed Sawyer

I too have CLS. I have a pair of home-built subs, using NHT1259 drivers in approx 2.8 cu. ft. enclosures. 2 is definitely better than one. If you have the time, inclination and skills, it's not hard to build better-quality subs than what you can buy commercially for anywhere near the same $. These two subs cost probably less than $600 for materials. Sure, you need an amp and crossover, but those are items you may have already (I did), and having them separate gives you more flexibility for future upgrades. I am more than happy with the way they worked out in my system, though I've been considering the Stryke HE-15 sub(s) as a possible upgrade/replacement. (www.stryke.com). Not like I need to replace these, but the Stryke driver just looks soooooooo nice.... ;-)

have fun,
-Ed Sawyer

I also have the clsIIz. I use two of the ML Descent subwoofers using xlr. I have them behind the clsIIz, about four feet. I really enjoy them and they integrate better than several Velodynes I have tried.

I agree that you may need lots of power circuits to run the gear. I also use a python or a whale for the power cords.