The Loudness Problem: Loud Commercial vs. Quiet Program (Part 1)

The age-old problem of loudness is rearing its ugly head again. Actually, it has never gone away, there were simply too many other things going on and too few people actually watching DTV signals. With the supposed cut off of terrestrial analog service on the not-too-distant horizon, the focus is shifting to digital services and one of the major complaints is the difference in loudness between commercials and programs. Not just commercials that are too loud, but perhaps also that some sections of programs are just too quiet.

The Dolby Digital (AC-3) system offers over 100 dB of dynamic range, a vast improvement over the limits of the analog system it replaces, but is all of this dynamic range useful or necessary? Having the ability to take advantage of this new extended range does not necessarily mean that it should be taken advantage of without some ear towards the results. Even if the dialog levels of program are matched--and this is very possible and straightforward to do these days--vastly differing dynamic ranges may result in loudness mismatches. This could mean that a commercial that is not too loud with some programming would be judged far too loud with programming that is mixed very quietly. There is research that suggests comfortable dynamic ranges for listening, and they are nearer to one tenth of the more than 100 dB available. Matched dialog will do little to combat large variations in non-dialog program material, and this is what results in consumer complaints.