Davy, I can fully understand you wanting to keep trauma to your ears to a minimum. In my young days as a pre-teen and teen in the 60's, we didn't use hearing protection when shooting. That wasn't too bad with rifles, but when I got old enough to own a pistol in 1974 I promptly bought a 5" 27-2 (still got it too ) and we used to go out and shoot a couple hundred rounds off at a time and our ears would ring for days after. Between shooting pistols , rock concerts of the 70's and working on drilling rigs I now live with hearing loss and tinnitus. And I don't shoot even a 22 without hearing protection now, as I am trying to save the hearing I have from deteriorating further. But if I had to deal with a BG in my house, I will let him have however many 357 Mag rounds as needed and worry about my ears afterwards. I think that the 357 Mag is about the most effective caliber I have to use in a defense situation in my house and I won't compromise my defensive capability by loading inferior ammo. And while you might be able to download a 180 grain bullet to subsonic levels and keep decent kinetic energy, I would worry about over penetration with that bullet. If you are still worried about hearing, then pick another caliber, such as 45 ACP with some 230 grain or 9MM with 147 grain hp bullets.

BTW, my living room stash gun is a 3 1/2" 27-2 loaded with Fiocchi 158 grain JHP ammo. It's right by my chair, for "just in case".