My personal pain
I love movies and audio, and I always struggled hearing dialog while not having explosions deafen me or bother roommates.
When we had a daughter, and she jumped from sleep with every gunshot on screen, I knew I had to find a solution.
I searched online hard, and I could not find a way to do this on my Mac — (without resorting to 100s of dollars of hardware like some determined folks do!)
So I built a prototype for myself, and it worked well enough that I wanted to share the joy with others.