Is this enough power?

I drive my B&W CDM9NT´s with a Bel canto SETi 40 (845 tubes) which have a nominal impedance of 8 ohms (the impedance curve indicates that about half of the curve stays below 6 ohms!!). I lisen to rock and reggae at a moderate to high volume most of the time with no problems at all. My room measures 10x19x9. IMO you will not have problems with your amp.

Thanks for all the responses.

I found an impedance graph for the speakers.

Between 1k and 20k it is 6 ohms and peaks at 12 ohms at 5k.

From 1k and below it is ruler flat at 4 ohms.

Does this new info alter any of the comments?

the amp does have a 4 ohm and 8 ohm tap. Not sure which one would be the best to use.

Thanks

Experiment with both the 4 and 8 ohm taps as you cannot hurt your amp or speakers.

Try both taps and use the one that pleases you most! In my set up I found the sound changes a bit been the 4 ohm tap the one I like most because the bass notes are more tigh and the music sound more "relaxed."

Good job getting the impedance data. sounds fine.
However, your job is not done yet! See if you can find some phase data. This IMO is the true test of 'good load/bad load'. Huge phase angles at low impedance will really drain all but the most robust amp. Speakers which are heavily capacitive do not like tubes....or perhaps the other way 'round.

Trying the various taps on the amp? Best idea yet.