Clean signal with clipping;
Notice the peaks are cut off.
People are mislead into thinking about amplifiers in terms of power
but a more important issue can be clipping headroom.
Your tweeter may only consume 2-3 watts of power, but a 2-3 watt amplifier
can easily chop off that signal. The side effect of the low powered amp is
the chopped waveform when you drive your speaker with low power.
The problem is solved if you raise the power supply voltage of the amplifer
design. The higher the voltage, the higher your clipping headroom is.
Lets say you made a higher voltage amplifier to give you higher clipping headroom, lets say it's a
+/- 130v design. That would be cool, most high powered home amps are +/- 90v, lowered powered amps
have much less voltage. This higher voltage design ensures clean transients.
The byproduct of your +/- 130v amplifier design is it's power rating. If you were
to design a good one, you would be testing this amplifier at over 3000 watts
in spite that you only wanted to drive your tweeters with no chance of clipping.
Your tweeter isn't consuming 3kw, but your tweeters loves the headroom as
you will rarely ever send a clipped transient to the tweeter.
If you want to be uber, bridge that amplifier and double your headroom and
he uber happy that you have crazy high clipping headroom. As you go down the driver
food chain, tweeter, midrange, woofer, sub, the clipping issue is easier to
manifest so you do need higher power as you walk down that chain of drivers.
This is just a common sense post, most people know this already.