How Much Difference Does a More Powerful Amp Make?


When would you notice a real difference in sound quality with a more powerful amplifier?

I have a Simaudio W-7 driving Dynaudio Sapphires, and at some point, I may upgrade to Sonus Faber Amati Futuras.

My W-7 is 150 watts at 8 Ohms, and Simaudio makes the W-8 at 250 W at 8 Ohms. Would I notice any difference if I moved to the more powerful amp in a medium-sized room (14' x 22' x 8')?

The Sapphires are 89 db efficient, the Futuras are around 90 Db, but I've read that with most speakers, the more power the better.
level8skier
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How would someone know if they were "running out at current power usage"? Is there an easy way you can tell that an amplifier is not powerful enough for your speakers? Or does that just manifest in "bad" sound?
Since you are moving within the same make and lineup of the amp you will probably not have "inferior" watts. So it is all about 150 vs 250 watts. With your speakers it is a big thumbs up to go higher in watts. What you will most probably hear is a more resolute, disciplined performance because of the grip the amp will have on the drivers. The sound might be bigger as well but it will be more graceful. To me these are important improvements. I have owned and heard many Dynaudios in the past BTW.
This Sims are very high current so I doubt you need more power. The W-7 is more than capable.
How can you tell whether an amp has high current? And, pardon my ignorance, but what's the difference between currents and watts?