Spanning the distance between average spoken dialog and the rest of the program takes experience. Film mixers have long been living by the simple rule that "dialog is king," meaning this is the one area that needs to be carefully textured so it is always audible. This is tricky because making a whisper seem like a whisper, and shouting seem like shouting, while simultaneously keeping overall perceived loudness consistent are diametrically opposed ideas. This is where truly skilled mixers can convey the intended emotions while not disturbing the viewers. If someone needs to reach for a remote control to turn the audio up or down, then there is a problem. As it is impossible in a movie theater to adjust volume from a particular seat, it is critical that the consistency be built in. Note that theatrical mixes also have the ability to be delivered with more than 100 dB of dynamic range, but rarely does dialog move from a comfortably audible and intelligible area.
Theatrical mixes have the advantage of taking place on calibrated mix stages. This means that for a given setting of the master volume for a stage, dialog will reproduce at a given loudness when averaging at the reference level (i.e. "0" on the mixing console meters), and this is consistent from stage to stage. Many television programs are mixed on the same or similar stages and benefit from this calibrated environment. Once dialog is mixed to a consistent comfortable level, the other elements are added and everything is fine-tuned, and the goal of protecting dialog is never ignored.
It would seem that there might be a good bit of television programming that is using too much of the available dynamic range. The mix probably sounds great in the mix room, but responsible and talented mixers know it does not end there. Even with the growing popularity of surround sound home theater systems, the vast majority of viewers still listen in stereo or mono, and the audio must fit. Making average spoken dialog consistent is part of the battle, but making the rest of this mix match this dialog is arguably the major problem.
