Just to add add to the conversation above, I find that I cannot listen to well-recorded classical pieces on my system due to my meager 90W/channel. I find I have to turn my Denon's gain knob to -3 (in order to properly hear the piccolos, oboes and the like) when I normally listen to -20 or -25 for rock, blues, jazz, etc. Then of course when there's a loud passage like brass and drums, it sounds terrible. My wife keeps saying that that's what the woodwinds should sound like and I shouldn't be turning it up to hear them "better".
I also find that out of the dozens and dozens of classical CDs that I've listened to as a result of recommendations from Johnk and others on this site, almost all have sounded flat and lifeless.
I'm not convinced that my second problem is amp-related because I have two in particular that sound absolutely fantastic. So I'm blaming the sound engineering for all others. As for my first problem, it's definitely the amp. When I crank it up that much, I run out of headroom.
And you may laugh at my half watt, but I boast a whopping 22.6dB of headroom