Since the original question was posed with reference to Klipsch speakers, and since I believe that they can likely achieve significant sound pressure levels with relatively low power, and since I believe that 140 Watts (even if it cannot do so for all channels driven all of the time) should be plenty of power (and that going to 200 Watts would give very little additional headroom), I stick by my first set of comments.

Jeff Mackwood

georg, it is necessary to find out if that 4 cyl is getting near redline. That's why I asked how loud he is playing it. It is also known that distortion in amps is far less than in speakers. The speakers must also be able to handle that extra power.

Most probably so. It would be worth knowing more detailed specifications of the Marantz amp section. Manufacturers have very different methodologies and motives in measuring and promoting their specifications. Current (amperes) and damping factors are also important factors when selecting an amplifier, especially if you will be pushing higher SPL's. Horse power is great, but it's where you are on the Torque Curve that is important if you want to pass with confidence.

Best,
Allan