No, and their responses confuse me also. A DSL model wires straight to the phone line with no filter installed between the modem and the phone line. The filters are needed for any other device using the phone line to prevent the DSL higher frequencies signals from interfering with those devices. In theory you could have a single phone line wired to a single DSL modem and no filter should be use. Only if other devices, (telephones, answering machines, cordless base units, etc) need to share the phone line does a filter need to be installed on just those devices, not the modem. A filter installed in front of a DSL modem would prevent it from being able to send and receive the DSL frequencies being used. A DSL modem should be able to handle a normal ringing signal without a problem.