imo; the ss13 audio-scape is quite barren, you can only hear most things if you can see them, which in my opinion doesn't make much sense. This changes that so you can hear further away, but falloff is much higher, so in reality you will only hear things relatively quietly when they're out of sight.
This PR increases the hearing distance of most sound by 9, excluding sounds such as antag items that are meant to be used stealthily
This PR also replaces Byond's inbuilt falloff system with something I made, (And thanks to potato for helping me throw together a formula for it). This fall-off system makes sound fall off more naturally, with sounds being full volume within a certain range, and then softly falling off until they are completely quiet. This makes for a smoother transition between "This sound is full volume" and "I dont hear this sound".
Co-authored-by: ff <ff>
