Some of today's DVD and Blu-ray soundtracks are so densely mixed that dialogue can be hard to understand.
When actors' lines are obscured by onscreen mayhem, you may miss important plot details. The dialogue intelligibility problem is even worse for people who are hard of hearing.
Here's a simple fix to improve intelligibility that also works like a charm for quiet, late-night movie watching.
Turn up the center channel volume level. Please understand, that's not the same thing as cranking up your receiver's volume control. Raising the center channel volume relative to the left/right and surround channels makes dialogue louder than the music and sound effects, so it's easier to understand what the actors are saying.
The easiest way to make the adjustment is with your receiver or home theater-in-a-box system's remote control. Check and see if your remote has a button marked "Channel Select." My Onkyo TX-SR805 receiver's remote has such a control, marked "CH SEL". It toggles through left, right, center, etc., and once I got to the center I used the "Level -" and "Level +" buttons to adjust the center channel volume.
Experiment to figure out how much louder you want the center channel speaker to be, but start with turning it up by three decibels. That might be enough, but don't hesitate to turn it up higher if that's what you need.
Of course, you can also use the CH SEL feature to boost subwoofer volume to taste whenever you switch movies or CDs. Or adjust the surround channels volume.
If the remote doesn't have the Channel Select feature, use the receiver or HTIB's speaker setup menu to adjust the center channel volume.
I've recommended this trick to friends for years, but Atlantic Technology's founder Peter Tribeman mentioned it recently to me. Tribeman prefers the raised center channel volume approach over most Late Night listening modes and I agree. You'll be able to listen at much lower overall volume and still hear every word. Give it a try.