Is there a simple, intuitive tool (for Mac) that I can use to normalize / master a group of songs with differing gains (RMS)? All the tools I have come across are either very expensive, complicated, or actionable one track at a time. Is there a way to apply a global gain setting? I don't want to spend a few days trolling the internet for a folder of contradictory information, and I don't need to become an expert in mastering along the way. I just need a simple easy to use tool. Thanks!