I don't know, depends on what is actually doing the expanding. To my knowledge, WindowsXP has no builtin multichannel expansion capability. If someone else knows differently for a fact, then I'd be interested to hear about it. Most likely it's either CMSS 1 or 2 which are Creative expansion algorithms. Both of these manipulate the audio in some fasion and do not just mirror front to back. CMSS 1 sounds like complete trash, like you are sitting in a large empty concrete room with no carpets. CMSS 2 is better but still pretty poor and something I couldn't listen to for any period of time. Some people like the effects, so just because I don't like them, doesn't mean you won't like them.