Louder SMPlayer volume

For some reason, a number of my shows and movies seem to be at a low volume. SMPlayer, my video player of choice, didn't seem to have a way of boosting the sound beyond 100%. Turns out it does, you just have to hunt for it:

Options->Preferences: General->Audio->Max. Amplification

Set that to 200 or so to allow further amplification in software.

Audio->Filters->Volume Normalization is another way to help boost sound.