This Recommendation provides the speech transmission requirements for Group Audio Terminals (GATs). The associated test methods for verifying the specified performances are contained in Annex A. An in-situ procedure for checking and aligning GAT terminals in the field is provided in Appendix I. Reference is made, as far as possible, to other Recommendations applicable to speech terminals for analogue and digital networks. Only terminal configurations not already covered by these Recommendations are addressed in detail.