This Recommendation contains the description of an algorithm extending [ITU-T G.711] for the scalable coding of narrow-band and wideband speech and audio signals from 64 to 96 kbit/s. This Recommendation is organized as follows. The references, definitions, abbreviations and acronyms, and conventions used throughout this Recommendation are defined in clauses 2, 3, 4, and 5, respectively. Clause 6 gives a general outline of the G.711.1 algorithm. The G.711.1 encoder and decoder principles are discussed in clauses 7 and 8, respectively. The transmitted parameters are presented in clause 9. Clause 10 describes the software that defines this coder in 16-32 bit fixed-point arithmetic. In addition to the algorithm specified in the main body of this Recommendation, Appendix I provides a supplemental functionality enhancing the quality of the decoded signal when a legacy G.711 or only the basic log companded PCM part is available.