Louder is better
It has been repeatedly shown in multiple independent studies that even just a small increase in volume makes music "sound better" to the average listener. Often you'll get all kinds of superlatives about accuracy, openness, full-bodied, etc, etc from the people comparing the louder track to the quieter one.

Loud CDs
In the past when record companies weren't so greedy they gave out CDs with normal volume levels. That way the artist could hit you with loud effects when he wanted. Then the ugly side of competition made the marketing droids increase the volume of the tunes to make it sound better, again and again, until we ended up with clipping.

http://www.cdmasteringservices.com/dynamicdeath.htm

Creative X-Fi 24-bit Crystalizer
Marketing strikes again. You may find 24-bit Crystalizer to sound better, but what it does is it boosts the low and high frequenzies. This makes it sound "better" on small PC speakers which usually are no good at low and high frequenzies. This is bloat made up by some marketing monkey and results in lower dynamic range and more distortion

http://www.digit-life.com/articles2/multimedia/creative-x-fi-part2.html

The sound of marketing
What if a lemming became victim of all three? Would the lemming experience the best sound ever, or would it find it tiresome to listen to and lower the volume?

"Have you ever heard one of those test tones on TV when the station is off the air? Notice how it becomes painfully annoying in a very short time? That's essentially what you do to a song when you super compress it. You eliminate all dynamics."

But something weird happens as you listen to it. You like the songs, but you don't really want to listen to it for very long and you're not entirely sure why. You take it off. A few minutes, later you put it back on. Same thing happens: You like the music, but you still want to take the CD off. It's more than a little weird.

Condolences. You are officially a casualty of the loudness wars, the ongoing competition among bands, labels and A&R folks to make ever-louder albums.

http://www.austin360.com/music/content/music/ stories/xl/2006/09/28cover.html

Try get a hold of Los Lonely Boys first album released in 2004, which wasn't subject to compression during mastering.