Topic: [Info] Understanding the audio gain methods,....
Since audio isn't really my specialty and I always struggle with it I attached a small sample which shows the effect the different audio gain methods have when using the Gain->auto option in Hybrid.
I hope this helps a bit to Understand their effects.
For more theoretically infos, I recommend to read the toolTips and the sox documentation.
Ps.: To watch the wave fronts of the files I normally open them in Audacity (mit the ffmpeg import/export plugin)