To give you the best balance of power and performance, select an amplifier or receiver that delivers continuous watts (many times erroneously referred to as “RMS”) in accordance with the speaker’s continuous power rating.
For example, a Klipsch RP-8000F floorstanding speaker is rated at 150 watts continuous. So, any amplifier that delivers right around 150w/channel at 8Ohms with full frequency bandwidth (20Hz - 20,000Hz) would be a good match.
However, don't be misled; although a speaker’s peak power rating can be much higher (in the RP-8000F, for example, it's 600 watts), remember that peak power means exactly that…a momentary exposure. Trying to make any speaker perform for more than an instant at peak power is an open invitation for damage.
The right amplifier, one that has it's power well-matched to the speakers, will also eliminate the need to overdrive components (play them too loud). Which, over-driving can cause clipping, which distorts the signal and can cause serious damage. Believe it or not, under-powering speakers carries as much danger as too much power. So, just make sure your receiver/amp's power output rating is right around what the speaker's continuous power rating is.
Horn-driven speakers, such as Klipsch, are much more efficient than their direct radiating counterparts and require less power to create great sound. Just be sure to keep the receiver’s output closely matched to speaker specifications to ensure years of trouble-free performance.