Dynaudio contour with 30 watt amp

How much power does he need to listen at "very low volume levels"? According to Dynaudio, his Contour 2.8's put out 87 dB with 1 watt of input. I'm assuming that he won't even be using 1 watt, since I do not consider 87 dB to be very low listening levels. So if he is not even using 1 watt, then 30 watts should be plenty.

Yes, you would think so, but in my expereience with several monitors of the same efficiency, a tube amp of that power rating, (a deHavilland to be specific) was not up to the job of really controlling the speakers and making the sing as they should. And that applied at lower volumes as well.

86 db is loud. I believe I listen to music at most at that level.
Is the sensitivity of this speaker measured by "2.83V/m"? 2.83 volt input and the microphone was placed 1 meter from the speaker’s front baffle.

If most of the amp send 2.83V to the speaker, then I only need 2 watts if I sit one meter away from the speaker.

Contour 2.8 has 4 ohm, so I guess it needs 2 watts of input to put out 87 dB.