Originally Posted by Anhydro
I just upgraded to Studio CC-490, fronts Studio 20's, and rears Studio 10s... all with a Denon 3312ci. I read a "professional review" that said the Studio 20s "could" perform well with as litte as 2 watts per channel.
Without a more complete context, I can't be sure of what the reviewer might have meant--it could be one of several different things. For example, some speakers perform better at louder volumes, and he might have been saying that these Paradigms sound good even when played quietly (but with full dynamics) with only 2 watts. It could also have been a reference to their efficiency, or both characteristics at once. Whatever he meant, it's not anything that goes against your choice of receiver or typical home theater usage.
This does, however, bring up the general subject of having too little amplifier power for a given set of speakers and volume, which can potentially damage speakers just like putting too much power into them. This is because the amp will "clip" the signal, effectively putting a lot of DC power into the speakers (in the extreme case), which can burn them up quickly. The conventional wisdom, if you look it up in forums, is that having an abundance of amplifier power is safer because it won't clip the signal, and there is some truth to this in some cases. However, in practice, you can clearly hear the nasty distortion that results from the clipping of an underpowered amp (you'll know it when you hear it), and most people with any sense would immediately turn down the volume to spare both their speakers and ears (usually before either are damaged permanently). On the other hand, with more than enough amp power available, the speakers may sound fine right up until smoke starts pouring out of them, as there is sometimes little warning of speakers reaching their limits of power handling (you may hear them distort and compress, but it's more subtle than clipping). So arguably having an abundantly powerful amp/receiver is more dangerous than an underpowered one, despite the popular belief in the opposite. It depends on whether you're the type of person who would keep cranking up the volume despite how bad and painfully "loud"--usually a result of clipping distortion as opposed to actual loudness--a speaker sounds, and unfortunately it seems that plenty of people are.
That being said, there is nothing to worry about as long as you operate both the amplifier and speakers within their limits, and for most people most of the time, this is not an issue.
Originally Posted by Anhydro
With my HSU subwoofer having its own amplifier, I have assumed the Dennon 3312ci will have plenty of power (and is an upgrade over my current AVR). Should I be comfortable using the Denon with this set-up?... fingers crossed.
Sure, unless you want to really crank the volume up very high, in which case you'd want to consider more powerful separate amplifiers and speakers that are designed expressly for high output. For most people, though, a setup like yours could play as loudly as they'd ever want in a typical home theater.