"Or just turn your music down so that you don't annoy your neighbor. Simple."
I've lived in my interior town home since 1975. They were built in the 60s, and very well insulated.
There have been three different families next door during this time and two on the other side.
Up until now, I haven't had any comments, or complaints, about the two-channel stereo in the living room.
The new family moved in five months ago, and the wife/significant other immediately started to gripe about "that noise" from my system.
I turned the sound level down appreciably, - - but she's kept on griping about "that noise."
So, if I want to listen to my CD collection, I'm relegated to listen via a decent headphone. I even bought a BHA-1 to drive the Sennheisers.
My Grandchildren nicknamed her "Bat Ears," and it's stuck.
The opposite neighbor is getting serial complaints about the noise her dog makes in the morning.
No one else in our row of townhouses has ever complained about the dog - - just "Bat Ears."
BTW: I do have two phone numbers and two phones - - one for home, and the the other for fund-raising for our community hospital and the National Cathedral, That one attracts the malware and viruses.