[MPlayer-dev-eng] [PATCH] audio filter volnorm2 - two-pass audio normalizer

[Ivan Kalvachev]

[snip]

> Explanation:
> AC3 5.1 sound on DVDs is usually not loud enough
> and needs aplification. There is number of ways to make
> it louder
> (like -af volume or encoder gain), but you must either
> guess gain value

Have you tried -a52drc option?