Adding a separate amp to AVR?

Hey everyone, I'm wondering if there would be any benefit to me adding a separate SS amp to my Cambridge Audio CXR200 AVR? The AVR is said to produce 170 & 270 wpc into 8 & 4 ohms. The AVR is used for a mix of HT and music, and is driving my Wharfedale Reva-4's (88 sensitivity and 8 ohms). 

The reason I'm asking, is because I do NOT listen my music very loud. Usually, low to moderate levels. 

Thanks for any help!