one or two Sub-woofers?


I am considering a purchase of either one Audio Physic Minos sub-woofer, or two Audio Physic Luna subs. The total value of either package will be almost the same. My system consists of Martin Logan CLS speakers with VAC amplification. My listening room is of medium size. I would greatly your opinions. Thank you in advance...
meta
1. What is your front end and wall juice? If either are lightweight you may not be getting the sound you want.

2.I would RESPECTFULLY suggest you eschew subwoofers in favor either a Wolcott amp and/or Sound Lab M-1 or A-3 speakers. All of these items are final purchases.

3. Finally, and most relevant, your room may not support the weight you wish.

If you wish email I have been down that road.

Enjoy,
I would recommend getting one of the better one. The quality of the bass is more important then the quanity.

But then down the road I would upgrade and add a second one. Of all the upgrades I ever made to my system adding a second sub was one of the best. Better imaging and seperation and was more like a cable upgrade then just adding more bass. I was also suprised in how much it cleared up the sound.
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