Originally Posted by EddieVanHalen
Then please explain me and some others what exactely Dialogue Normalization does as some of us may be a bit lost here.
Dialog normalization was designed to help broadcasters and studios mitigate the various recording levels of programs, and hence the swings in volume.
It does this by measuring the average program level of dialog above or equal to the reference point (-31db..)
Then, when the codec is decoded, the resulting PCM is lowered said amount.. this is done to the entire program, not any single channel.. it is a post decode process, and done in the digital domain..
This is a simple explanation, and doesn't get into the variety of other designs of the technology or decoders (i.e. THX receivers, metadata for dynamic range compression, etc...
Unfortunately, it isn't usually properly measured, and most Dolby encoders, both software and hardware, leave the DN value at the defaults (which is -27/+4.) DTS authoring software has the default value set to -31 (which is essentially bypassed/off.)
What does this mean for you? When you see a DN value on the front of your AVR, or in the menu, and want to listen to it at "reference level" (and know what that is for your AVR) you should raise the master volume up the specified amount to achieve "reference" value.. (THX receivers use a combination of volume display offsets and compensation so you don't have to turn up the volume...)
Please note that dialog normalization exists on both Dolby TrueHD and DTS-HD codecs.