A tool / filter / technique to tweak dynamic range

I suggest a tool / plugin / technique that will allow the tweaking of a recordings dynamic range. A simple tool that let the user spec the bottom and top of the dynamic range would be great.

My reason for this is that setting the volume loud enough to hear the soft passages, while driving, will blast out your eardrums a moment later.

There already is one, it’s called a Compressor.

It’s not as easy to use as the idea you describe, but it does work if you research the topic.