If I owned speakers rated for 45-300W, I would be good with 100-200 WPC amp.
The salient thing is to never play extremely loud.
But if you're asking if too much power is more dangerous for your speakers, that's another hot topic that's been debated forever.
This is my take on this subject based on my studies at the University of Google (like that?
@PENG)
What damages speakers?
1. The actual clipping or distortion?
2. The actual POWER/ENERGY being sent to the speakers?
The answer is the actual ENERGY/POWER being sent to the speakers causing Thermal and/or Mechanical damages.
For example, if a speakers has been tested to truly handle 900W, a 10 WPC amp will NEVER be able to damage the speaker. However, a 500W amp could damage this speakers if the amp clips.
What happens to the POWER output to the speakers when the amp clips? The power output could DOUBLE. So a 300W amp could output 600W when it clips. A 500W amp could output 1000W.
So if your speakers can handle 300W and your 300W amp clips, your speakers could get 600W of "clipped" power/ENERGY. Thus, your speakers would be fried.
That's my take from my studies at the University of Google.
Would also like to hear what other members think (
@TLS Guy,
@M Code,
@shadyJ,
@TechHDS, and others).
Is there already a thread or article about "What causes speaker damages"?
For full disclosure, I have never ever blown a speaker in my life.