This topic comes up often. This is my understanding of it.
You start with an input signal from a reference disc, -20 dbfs. That input should lead to an output of 85 dbs. At your listening position. If you do that then the loudest part of the movie should be 105 dbs.
Sometimes members talk about reference level as 0 or such on an AVR. But reference dial number will be different based on the room, the speakers(location and sensitivity) and the location of the listener.
Reference level is loud.
Add to this if you know more or if I am incorrect.
