phone company may be able to answer this one.as i think they have a full house filter for in the box. as the standard 'filter' will than have to filter more than what it probably is rated for. the rule for the dsl filters is one for each outlet, and then split your phone/answering machine off that.unless you have more than, what is usually 2 or 4 filters.

but there is also the condition of the lines in your house. are they old as the mice chewing on them and for speedier dsl on your lines, it could be good to run a new line .

I had the DSL split from the phone signal at the point where the phone lines come in to my house. The phone company put in a rather nice, modular, splitter unit. You can see a photo in the first image of the following article:

http://www.oreilly.com/news/dsl_0501.html

I happened to be my phone company's first, paying DSL customer. I was their second install after their own technician. Since then, I've been told they do not like to put in whole-house splitters, and I think it's because of cost. So you might need to press the issue a bit with your phone company, but it definitely is possible. Don't let them tell you otherwise.

Jonathan Gennick
http://gennick.com

The only thiung wrong with dsl splitters is the fact that once one goes bad, if one goes bad you lose phone service to the whole house. Luckily I had a spare inline filter lying aroung to plug into the dsl jack to get my phone working again.