Digital transmission of high-quality sound-programme signals using one, two or three 64 kbit/s channels per mono signal (and up to six per stereo signal)
The ITU-R Recommendation BS.1115 recommends, based on extensive tests carried out by ITU-R Study Group 10 for different applications of the transmission in a broadcast chain (contribution, distribution, emission, commentary), the bit rate reduction system according to ISOAEC 11172-3. The encoding layers and bit rates (per mono channel) recommended by ITU-R SG 10 depend on the application and are in the range of 120 - 180 kbitís using Layer II, except for commentq where 60 kbit/s using Layer III may be used. For details, see ITU-R BS.1115.