Yes, just make sure you get a splitter designed for that,
Get a splitter and connect it properly.
That has a lot of downsides, and I only recommend it if four things are true:
1) You aren't a hardcore user who wants every bit of performance out of your DSL connection. 2) You don't have or plan to add devices like alarm systems to your phone line. 3) You rarely if ever change around your phone wiring. (For example, you don't have a fax machine that you sometimes connect to one phone line, sometimes to the other, and most of the time it's in a closet.) 4) It just happens to work for you, that is, you get the fastest DSL speed available for your service class, see few if any data errors, and almost never lose sync.The problems with using cheapo filters are many:
1) If you have a jack anywhere in your house that you don't use that's in poor condition, it will degrade your DSL quality. 2) If you have or add an obscure device somewhere that you forgot about (satellite receiver, alarm system, answering machine), it can degrade your DSL quality. 3) When you add new devices, you need to add new splitters. 4) If any of the wiring in your house is low quality and/or goes past a source of noise, it will reduce your DSL speed or cause you to lose sync intermittently.DS