To give you a further idea how watts per channel compare on paper: To have an amplifier that will play twice as loud as your 40 watt amp; you won't need 80 watts, you will actually need 400 watts.
Am I hurting my speakers?
I have a pair of Yamaha NS 1000M speakers that are rated 50w continous and 100w maximum, and they are being driven by a Creek 4330R 40W amp. I think they sound nice, and have not heard any distortion on my tweeters. I think the amp is rated at 40w idle and max 200w. Am I okay or am susceptible to clipping, and would I even hear it?