Networks A q about ADSL

That isn't entirely true. The filters cut the modem off from voice call frequencies and your phone calls off from the internet frequencies. Without the filter if you use the phone you will be getting any high frequency background noise interfering with the ADSL connection which will usually end up in it being disconnected.

USE the filters, they're supplied with practically every ADSL modem for a reason, and that's because without them your connection will just get cut off every time the phone is used.