I tried side by side the n8 and the voodoo samsung i9000.
The samsung smashed the n8 to bits. It wasn't funny. It wasn't close. And I this was pretty consistent with whichever headphone I used, ranging from £10 ones to £1000 ones. There were a few that displayed very little change between both phones though.
I've tried around 12 other smartphones and the samsung has come out on top all the time. Actually, nowadays I can't be bothered to waste any more time testing out smartphones as I've found my staple.