According to what I know.... Some classical musical pieces may have 60dB between the most silent passages and the most extreme crescendos
That means if the amp is giving 0.1 watt for the silent moments, you need 10.000 watts peak power for the crescendos
Let's putting things in context here. During the "most silent passages"s it is probably pretty close to practially "silent", say 45 to 50 dB or as low as just the ambient noise in the concert hall, it would therefore require something close to 0 watts, say 0.001 watt, or 0.01W. So going from such low SPL, you will not need anything that comes close to 1000 watts to increase the SPL by 60 dB let alone 10,000 watts In fact, I was just listening to a violin concerto, during the beginning of the first movement, the wattmeter fluctuates between well below 0.01W to a little over 0.02W occasionally, with volume at -20. That 2Ch system has No sub in use, just the R900. That's why I think people who exaggerated things by using extreme examples to make their point could also mislead people.
Also, keep in mind most people own speakers that cannot play louder than 115 dB without losing their composures, whether they are getting "clean" power or not.
So the XPR-1 will probably not even be close to meeting these requirements, and neither will probably any speaker on the market, if you turn down the volume quite a bit then, possible you're better off but to have any chance of replaying very dynamic classical music you need extraordinary amounts of power and also same hi-end speakers
As explained above, no that is not even close to being true, unless the room is large and you have speakers such as the Salon2 or Gene's Status Acoustics 8T. Even then, those speakers cannot handle much more than 1000 watts either.
So I don't think XPR-1 has too much power, probably there's never too much power for an amp
I said that many times myself but obviously for different reasons than yours. To me, it is a matter of having power you don't need but be aware that you are then just buying nothing more than insurance policies. If I had not been paying for my life insurance for so many years, I would have own at least a pair of Salon2 by now.
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Instead, I own no fewer than 5 power amplifiers at the moment so I am not telling anyone not to buy a lot of power, just simply caution you not to expect any miraculous improvements in sound quality from power you may not need and won't be used in your situation.