Watts and power

The impedance curve of a speaker takes into account the reactance already and hence the current. Few speakers dip below 2 Ohm. Some do, but they are rare. If your speaker doesn’t dip below 2 ohms than having an amp that doubles in power into 1 ohms is likely paying for something you are never going to use. Their is more to doubling into 1 ohm than just beefing up the supply, and there is no guarantee that the trade-offs , like higher feedback, are going to sonically pleasing. This is why "rules of thumb", like doubling of power into 1/2 the resistance is "better", should be taken with a grain of salt.


If your speaker does not dip to low ohm, then a so called beefy amp will not sound any beefier, but one with higher voltage rails and more capacitance will, even though it can't double into 2 ohms or 1 ohm or whatever artificial metric you want to use that may not apply to your system.

As a very general rule of thumb: I think it safe to suggest that one double the speaker manufacturers minimum power recommendation and to consider amps that can double down that power to that speakers minimum impedance. Again, just a general rule of thumb! 

That cos term and the ability to act as an ideal source as the load impedance drops, is what makes most of the difference when it comes to balls.

This isn't true across the board. You can have lots of drive without anything near that if you simply are careful about the load. Some speakers are easy to drive and some aren't, but one thing is true about **All** amplifiers: the harder you make them work for a living the more distortion they are going to make, so if sounding like real music is your goal then your amplifier dollar investment is best served by an easier to drive (including higher impedance) loudspeaker.

An amplifiers watts or amps is much like a cars topspeed, just a number. It says wery little about it`s authority, it`s punch or torque.  The amp`s weight might indicate some grunt, but just that. 
Why? because it is all about how this amp are capable to deliver it`s power fast enough. And that again depends on the internal cabling, trafos included.

And while I`m on, dampinfactor calculated from output impedance is a misunderstanding, it means nuthin. But tell me the size of your secondarys..

sfischer1

+1 you have your finger on the pulse, and know about current delivery and wattage doubling, also about bridging stereo amps.
Others here that say a $350 3000w Behringer amp solves all that are just p*****g against the wind and some just beating their own commercial drum.

Cheers George