Noise-canceling headphones block the world out, but they also block out the bike bell. Tune out carefully.

Filters do not discriminate. Whatever you set up to keep out the noise will also keep out the warning, the invitation, and the thing you would have wanted to hear. This applies to headphones and equally to muting people, avoiding certain topics, and deciding in advance that a whole category of input is not worth attending to.

Look at what you currently tune out automatically. A person, a type of criticism, news of a certain kind. Pick one and let it back in for a week at low volume. You may confirm the filter was right. You may also discover you have been missing the bell.