I have 3-way towers that have twin 8" woofers in each cab that are rated 3db down at 30hz. I also have a modified Behringer DEQ2496 as my DAC which gives me parametric EQ. Lots of power conditioning in my setup has increased its bandwidth on top of that. With all that I personally just don't miss having subs. But, I've had a rig with a single sub in the past. The one thing I like most about my current setup is having stereo bass. You may not think it a big deal, and I imagine most people might be willing to live without that, if they felt they needed to. But, having lived with this arrangement a number of years now, I've found this aspect to be highly satisfying...it really does add to the soundstage in a fundamental way when the bass is fully stereo. In my rig the bass just "images" just as well as the rest of the spectrum. It would now seem unnatural to me if the bass instruments were "always in the middle" and I were aware that they were somehow "disjointed" from the rest of the soundstage. I suppose I could get used to that again if I had to, but why would I want to if I didn't have to? Of course, you can always resolve that problem by using a pair of stereo subs. But, in a way, that's my point. Stereo subs, while certainly a good idea performance-wise, can lead to rather a LOT of hassle when it comes down to the nitty-gritties of all the extra expense and individual problems that need solving. From finding the ideal sub candidates, to the right amps and the right wiring, to EQ, to crossover frequencies, room placement...and so on. But, you know what? Two good towers with solid bass performance to begin with (and they are out there, you just may have to look - unless you're already sold on the 220's) can cut right through all of that in one simple, direct purchase. If you have the budget for it and you're not afraid of the complexities, then you may want to go for it. Many would do that just for the fun of it. But, if you're looking to keep things in perspective, then this may be a good opportunity to stand back and re-examine things with an eye toward simplicity. Between my past system and my current one, I have found the other bass attributes: dynamics, articulation, tone, extension etc, to be basically a wash - it really depends on all the individual pieces of gear and setup. But the stereo-vs-mono deal is the one thing that will be locked in by your arrangement choice - unless you choose to go that extra step with stereo subs. Hope this helps.
