watts?

[nerd513]

is it more watts for speakers than amp or more watts for amp than speakers?

[KennyB]

Well,

if you run a 10W amp into a 1kW speaker then you'll be safe as long as you don't run the amp so hard that it is clipping for long periods. That could damage the voice coils of the speaker over a time and would but sound horrible anyway. The amp needs enough power to deliver clean transients.

If you run a 1kW amp in to a 10 W speaker and turn it up you'll fry the speaker. Unexpected transients (clunks and pops) could damage the cones suspension quite easily.

So try and match the power the amp delivers to the power the speakers can handle.
If you want to monitor LOUD, so look at the excursion of the cone and if it looks dramatic and sounds distorted then you're driving it too hard - if you've seen a pair of NS10s being driven hard by a big amp you'll understand.... Watch those cones flap!!!