I found the 804s WAY too anemic in my room, and much preferred the 803s. Neither cohere well in the nearfield, so your 9' listening distance I consider a minimum for the Nautilus. Good luck.
PS If your budget dictates the 804 level, and you prefer to not get a sub, then I'd seriously consider the Revel F30 instead. Much better than the 804 alone, and I actually preferred it to the 803.
PS If your budget dictates the 804 level, and you prefer to not get a sub, then I'd seriously consider the Revel F30 instead. Much better than the 804 alone, and I actually preferred it to the 803.