HTRegz, being closer does give you a better connection. That's one of the reasons why DSL suppliers can increase the speed by adding amplifiers / DSLAM points. It depends on the distance for your modem to sync with the line speed. Therefor if you are within 500 metres of a conenction DSLAM you can get 8Mbps. This is impossible at more distance. ISP's need to search the ideal mix between speed and overall stability. If your network has many users that are on the edge of max distance you cannot increase speed without loosing on stability (sync). If many users are close to centrals you can easily gain up without loosing sync stability. The distance is thus on of the major issues for a DSL line. But you don't notice cause the telephone companies asure everyone has reasonable speed and stability by adding network equipment.

About getting a DSL modem not from your ISP itself. I purchase my ADSL equipment alwaus myself at some other point. Cause this way I can choose what brand and connections, Alcatel and Ethernet offcourse You always need a PPPoE authentication before you can surf. So you can line sync your modem when ADSL is setup on that line but you need an account and password to connect to the servers.

About filter, filters are necessary to keep the ADSL signal clean, simple as that. ADSL operates into the higher frequency areas of your normal telephone line.