room size for Pass XA30.5 power amp

I am planning to buy a pass Lab XA 30.5. I will be using this amp in a room size on 15Feet x 20 Feet. would it be powerful enough?
Most likely, but it is very dependent on your speaker's efficiency.
As a rule match your room to a speaker and the speaker to the amp.
Brf is right, it`s about the speaker`s sensitivity and efficiency. My amp at 8 watts is less powerful than yours, yet it completely fills my larger room(14'x26') with sound energy and presence without stress or strain. What is your speaker?
You will be fine unless you listen at extreme volume levels. Make sure you have great cooling in that room as the Pass amps run hot, but sound fantastic.