In recent years much work has been done on ways of enabling broadcasters to make broadcast sound more comfortable for listeners and viewers. This is done by monitoring and controlling audio 'loudness', so that it remains consistent. In this way viewers and listeners do not have to 'readjust' the sound level between programmes, commercial breaks, or channels. The instruments for measuring and monitoring programme 'loudness' are evolving in their accuracy, and a step forward has now been taken.
Gating to improve loudness measurement
The ITU-R is set to adopt a technique known as 'gating', the details of which have been proposed by the EBU as a result of the work of its PLOUD group. The essence of the technique is that sound is monitored leaving out quiet periods, below a given threshold, from the measurement, because our perception of how loud a programme is chiefly determined by the loudest passages - called the 'foreground sound'.
The EBU recommends that loudness meters include audio gating. The ITU-R Working Party concerned ('6C'), the worldwide body that develops Recommendations for broadcasting, agrees. It will be proposing to the world’s governments a new draft Recommendation on this. It will be some months before the international approval process is complete, but we are on a course for easier listening for viewers and radio audiences throughout the world.
For more information on Loudness, see the Loudness section [http://tech.ebu.ch/loudness] on this website.