Although some speakers can help, the real problem is how they record programmes now, and particularly if a film made for cinema is shown on tv. this is because they record differently for the cinema, and many directors have said they put sound effects and music at a higher level than speech.
Its one of those things where what is meant to be an improvement as an end product is worse. In the olden days(!) when each person was recorded with a microphone hanging over them speech was always audible. Just as when you watch the news or something there is never a problem hearing (even if depressing).
Now silly techies who probably never listen back to what they have recorded have directional mikes and so on, and seem incapable of then mixing (if that is the word) the dialogue so it is in front of the sound effects.
I watched a film shown on tv (some sort of sci fi) and usually listen at level 12 on my tv which goes up to 30, but however loud I turned it up the lead actress always seem to be whispering. And if I did have it turned right up to 30 all the sound effects of aliens arriving etc., nearly blew my speakers (and me off my sofa).
If a sound bar has the option to change different strands through what I think is called an equaliser, it might help as you can then change the levels yourself. I think sound bars etc only came in because flat screen tvs cant have the depth of speaker that the old tvs with the big tube could have.
There have been 2 recent BBC3 series I wanted to watch and just gave up as you could never bring the voices as they were always behind everything else.
You would think they would at least test a tv programme before releasing it to make sure it works on a tv set.
My rule of thumb is that if you cant hear people reading the news or on a discussion programme but not a tv series, its a production fault of the series. I've got tired of complaining.
Sorry for the long post but it drives me wild. You record something, settle down and within 5 mintues realise it is just going to be irritating to even try and watch. far from being relaxing it just winds me up.
Phew - feel better now for sharing! 