Bookshelfs + sub vs. towers

[cjv998]

For stereo sources (i.e. music), I've heard some people prefer bookshelf speakers (along with a sub, usually) over tower speakers. It seems like one can purchase a set of bookshelf speakers and a subwoofer for the price of a pair of tower speakers (for example, Paradigm Mini Monitors at $380/pair and a Hsu STF-2 sub at $380 shipped, for a total of right over $750; versus, let's say, Paradigm Monitor 7's at $650/pair or the Monitor 9's at $900/pair). I only use Paradigm as an example because I am familiar with their lineup, and actually own the Mini Monitors and will be buying an STF-2 in the next week or so. Anyway, my point is, you can source a pair of bookshelf speakers and a subwoofer for the same price as a pair of tower speakers that often incorporate similar drivers as the afore-mentioned bookshelf models. Is there a general consensus as to which gives better sound quality? (Basically, you trade one dedicated subwoofer for several somewhat smaller bass drivers.)

[zigzagflux]

One advantage that I can see is the ability to place each speaker where best applied. Obvisously, the 'bookshelf' monitors may not be best applied on the shelf, but at least you have freedom (with a pair of stands) to place them where they sound best in the room. With the wife-approval factor taken into consideration, of course.

With a subwoofer, though, it might sound better in a corner, in the middle of the two monitors, or at your side (stereo subs, ideally). All very dependent on room modes and such.

The point is, you can place each speaker where it performs the best.

Most subwoofers are powered, which gives a little more flexibility in amplification.

[Stormrider]

If you're going to buy retail this solution is exactly probable as it gets costly, but for the diyer it can be awesome.

Stereo subs crossed activly to the bookshelfs. I use a pair of 10" subs crossed at about 120hz to Modula MT's (7" bookshelf). This requires two stereo amps, or a stereo amp and a pair of plate amps, and an active crossover such as the Behringer CX2310 i use. IMO, it offers the best performance.

[Timn8ter]

Both solutions have their advantages. The previous descriptions for bookshelf + sub are pretty good.
The advantage of a well designed three way tower is the ability to use larger drivers that can produce dynamics a smaller driver cannot. The LF section can be crossed higher than a sub because the effect of LF localization is not a problem. This allows a 12" woofer for example to run up into the 200Hz range giving a great deal of impact to upper bass frequencies. Cross to a 6" or even a good 4" and you keep the smaller driver away from over-excursion which can give you a cleaner mid-range especially if you use a nice tweeter that can be crossed around 2k or maybe a touch lower. I find this especially helpful with large orchestral pieces that have quiet passages followed by huge crescendos. It's hard to recreate those types of dynamics at close to realistic SPL levels with bookshelf speakers.
Just MHO of course.