Enhancing voices

[makosipper]

When I don't use headphones, either if listen watch a video on my computer or connect the cables to watch it on TV (in both cases, the videos are played by the computer, since I don't have a DVD player other than my PC's), the voices become very faint and I barely hear them, especially when there's some loud music going on...

I've read something about raising the sounds in frequency between 300Hz and 3.4kHz, but it didn't really work. Ok, the voices got louder, but so did the background music. Is there a way to do this? Furthermore, is there a way to save a personal preset equalizer setting?

Thanks