I use an xls1500 for a set of towers, and an xls1000 as a sub amp. They sound great (though I am skeptical that there are sonic differences between amplifiers provided that they aren't overdriven and have identical measurements). At any rate, I looked at frequency response graphs for these before I bought them, they are very flat across the whole audible range. There are two Caveats for this. First, ome of the lower end amps have high noise floors, which could be problematic. For example the noise floor on the xls1000 differs from the xls1500 (the rest of the series is identical to the 1500 but with more output) even though they are in the same series. Second, some lines have fans that come on easily (the xls series never come on for me) these fans are way too loud for home use and will ruin the experience.
Here is the frequency response plot for the xls-2500 (though this should be the same for the 1500 and 2000 also, but not for the 1000)
http://www.prosoundnetwork.com/artic...pr-1600/11870# ( you'll have to go to page two of the review to see it. For some reason I can't directly link to the second page) note that the first plot is the crown and the second is a competitor.
Here is a professional reviewer's experience with them for home use
http://www.arccinema.com/crown-xls-d...lifier-review/. This one is a long read, essentially he says that the xls series are great, but DON'T get the xls1000.