this is so offensive it reminds me of my dad ♥♥♥♥♥♥ me when i was a child

I know what you mean. I don't have a directional microphone array but tried filtering out city noise from where I live with a Fourier-frequency profile filter and maximizing interesting sounds.
The most interesting sounds I found was from analyzing static FM-radio transmissions.
In the future I'd like to get an amateur-radio certificate and do stuff with packet radio.

having operated both active sonar and passive sonar for real, this is as close to the real thing as you can get, obviously a lot of the real stuff is restricted for security, but still gives you an idea of what a sonar operator has to work with