If not silence for you, then how about white noise? From what it sounds like, all those passive background noises must create quite a bit of it. How do you feel about that? Is white noise a sufficient replacement for silence?
There's "silence" and there's "soundscapes." I love the sound of the aquarium. It's a gentle trickle of running water. One thing I don't like is the ticking of the appliance timer that controls its light, but that's a $8 part that I haven't bothered buying. Bet you didn't know appliance timers made noise, did you? The clock is marvelous. I own a surfeit of clocks; I'm not quite Doc Brown in Back to the Future but it's pretty ridiculous. The projector is hella quieter than the last one I had (a $15k Christie from back when projectors were expensive) and unlike the last projector, the cooling fan is only on when it's running. When it's running, I'm generally watching TV. It has taught me how much I dislike refrigerator noise. When I move back to a house from an apartment, I'm definitely remoting the compressor and condenser. Which will put me squarely in the commercial category and that's just fine. When a split-door LG costs $3k I'm cool spending $3500 on restaurant-grade stuff. And really - we're discussing the sound of a running refrigerator and the sound of an appliance timer - two things that people rarely complain about. I'm simply pointing out that they aren't silent. Could be worse; my father's house is nearly silent (now that the dogs are dead) so in order to keep down the roaring of the tinnitus in his ears he has a steady stream of baroque music playing 24/7. And hey - at my place in North Hollywood it was usually the ghettocopter that kept me up.