Riddle me this...

Marketing. People believe that they are getting more for their money when they get big power. They don't know anything about signal paths or idle-current noise, or amp classes. All they know is that they got 250 watts. When their business associate comes over to be impressed by the new audio system, he is supposed to say,"Wow!". If he says,"You paid all that money for only 25 watts!?", then you have failed to impress, and must go out and buy a much higher power amp, that will pass the "impressiveness" test. Much better to buy the "impressive" amp first, so as to not embarrass yourself in front of your associates.

It's the same thing with exotic cars. The vast majority of exotic car owners couldn't drive their way out of a paper bag. They wouldn't even know the first thing about it. But that doesn't stop them from buying a Porsche, and telling their associates that it has 330 hp and cost $120k. If Porsche depended only on buyers who actually understood, and could properly use, their cars' potential, they would be out of business overnight.

Get it?

Trelja, a very eloquent post! I enjoyed it thoroughly.

I'd like to add, that the speaker manufacturers are complicit in this deal. When the majority of speaker manufacturers are putting out multi-way speaker systems with sensitivity ratings in the mid 80 db range, that is going to require high wattage amps. And then on top of that, they make the speakers with a 4 ohm load, or even a 2 ohm load. It seems like the speaker makers are making every attempt to make a speaker that any amp will have trouble driving. Like some kind of "sick joke". I'm waiting for a speaker maker to come out with a speaker made of a solid bar of copper, with a zero ohm load, and a sensitivity of about 1db/watt/meter, and say "here, drive this! It gives perfect uniform response from DC to light in our pure-vacuum outer space test chamber, and is truly reference quality when driven by a 100 gigawatt nuclear reactor".

None of this is needed for proper audio reproduction, and many audiophiles are realizing that a reasonably efficient speaker design, with a moderately, or even low, powered amp can give excellent results, with equal or better sound than these giant boat anchors.

If your "dream speaker" is a 80db/watt power eater, then you need these high power amps. For the real world, it is totally unnecessary. And remember, if you do get amps like these to power your "dream speaker" it is not a free ride. You are paying the price of many additional gain stages and signal loss, which may actually reduce the sound that those speakers are supposed to reproduce. To say nothing of the hole it will put in your wallet.

When speaker makers start making their flagship speakers with 8 ohm loads and 95db sensitivity, then we will see the amplifier market change.

I'm with Harvey(Dr. Gizmo).

I'd like to put my 2 cents in regarding these last few posts, that have alot of merit in them.

Nothing is perfect, and we will compromise in whatever we get.Like Sean says, it takes surface area and power to move alot of air for high-SPL deep bass response. Like Gregm says, it takes speed and maybe even some unknown things to cover supersonic frequencies, which may affect the listening experience in yet unkown ways. Like Zaikesman says, there is becoming less difference between high power amps and low power, in terms of accuracy, and sound quality.

So again, it comes back to what each individual wants in their system. A person that uses single-drivers and low power amps, like myself, would be foolish to think that he's going to get 125db at 20Hz out of his system. It is not going to happen. Conversely, there are different sacrifices made when someone selects a system that will produce that kind of SPL/freq. As Gregm points out most full range systems require multiple drivers, maybe multiple amps, alot of gain stages, low efficiency drivers, volumetric efficiency sacrifices in the enclosures, possibly equalization, crossover distortions, longer signal path, etc. If these trade-offs are considered to be acceptible for the SPL and frequency extension desired, then that is a fine choice.

But, there is no free ride. You will make sacrifices that accompany your decisions. There are many who think that they can get the sound quality of a good low powered SET, from their Godzilla amplifiers, and this is simply not the case. There are some who think that they can get the SPL and frequency extension of a high-powered SS system from their SET's, and this is simply not the case, either. It is a "pick your poison" situation.

Of course, there are certain applications where there is no choice, such as sound reinforcement for theaters, or stadiums, or hard rockers who must play music at 120db. For all others there is a choice, as far as home reproduction is concerned. The choices made will ultimately define the capabilities of that system.

Unfortunately, the "hyping" of certain products by manufacturers, magazines, or owners, in an attempt to make others believe that there is no sacrifice to be made in owning that product, leads to less-savvy purchasers being mis-led into thinking that they can have it all. Nobody has it all.