The answer is in your room size and how loudly you listen along with the impedance curve of the speakers. In a 14 x 20 room with a 90dB SPL monitor I use 55w of class a tube power and they are driven well. 25w from a SET mono I have is adequate in the same space. In my 20 x 40 main basement, neither is adequate at reference levels.
My speakers also have a nominal 6ohm impedance. Usually speakers measures at 4ohms are less sensitive than the measured spec due strictly to the way it is calculated. See any review for Tekton in Stereophile. It is in how the math is done.
so the answer is maybe, possibly probably but need to know more.