High speed communications system for analog subscriber connections

System data transfer at high speed for communication between a digital data source and an analogue subscriber connected to a telephone network (134) digital by a loop (122) analog, comprising: an encoder (150) coupled to said source digital data, said encoder converting an input (100) from said data source into a series of codewords from a set of codewords corresponding to quantizer values ​​utilized by said digital network (134) telephone; an interface (188) for transmitting said series of codewords in digital form from said encoder (150) to said digital network (134) telephone; and a decoder (156) coupled by said loop (122) analog to said network (134) digital telephone, wherein said analogue loop provides an analogue signal to said decoder, analog signal that is an analog representation of said series of codewords access, and inwhich said decoder is responsive to said analog signal to reconstruct said series of codewords in digital form from said analogue signal.