This European Telecommunication Standard (ETS) specifies the digital test sequences for the GSM half rate speech codec. These sequences test for a bit exact implementation of the half rate speech transcoder (GSM 06.20 (ETS 300 969) [2])@ Voice Activity Detector (GSM 06.42 (ETS 300 973) [6])@ comfort noise (GSM 06.22 (ETS 300 971) [4]) and the discontinuous transmission (GSM 06.41 (ETS 300 972) [5]).