You can never have too much power. Full stop.
This statement is only true in theory. In the real world where we all live, there are practical considerations that cause this statement to be false.
Apparently there is a need to explain why as I see a lot of myth in the posts above. If you look at the distortion curve of many amps, you will see the distortion starts at a certain level, **drops** as power is increased to about 5-7% of full power, then rises at power levels above that until it takes off at clipping.
Now the simple fact is that most of the time the music you hear is not requiring a lot of power- that power is needed mostly for transients.
If the speaker you have selected is very easy to drive, and the amplifier is very powerful, then you might say you have unlimited power since you can't clip the amp and stay in the room. But you won't be hearing what the speaker or amplifier can really do, since you'll be operating the amplifier 97% of the time **below** that minimum distortion point. Below that point, noise and distortion obscure detail due to the ear's masking principle. There will also be tonal aberrations as the ear converts distortion into tonality, and favors that over actual frequency response.
So there is a reason why matching an amplifier to a speaker on a simple power basis is good if **sound quality** is your goal! A very powerful amplifier works best on a speaker that is less efficient, so that you can operate at power levels where the amp is making less distortion. Conversely this is why a lower power amp sounds best on a higher efficiency speaker.
Now *some* amplifiers have a distortion curve where the distortion drops linearly to unmeasurable as power is decreased. If you have one of those amps, then you can have a lot of power on an efficient speaker and get away with it- have your cake and eat it too.
But there aren't many amps that do that, and most of them don't make a lot of power- being SETs. Now we make an amp that gets around this problem, because of our topography (and the lack of feedback) we are able to get this type of distortion curve. We're not the only ones- Nelson Pass is successful with this approach in some of his designs. Its tricky- the amp has to be linear at low power levels. Amps with feedback often have the feedback poorly applied (and so is not always able to correct the way it should) and so you see the distortion rise at lower power levels. One of the few solid state amps I can think of that has a better feedback setup is the Benchmark, and there are a few class D amps as well.
The point here is saying that higher power is better without taking into consideration how the amp behaves is the same as suggesting that flushing $$$$$ down the loo is a good idea. Its isn't. You have to take into consideration how it is the amp makes all that power. Now I happen to agree that paralleled devices to get more power is a good thing- that's how we do it as well. I've already outlined where I think the problem lies, although I've only nutshelled it for the sake of brevity and this is already a too long post.
