When a player deploys his weapon on a bipod he will hear a bipods sound, but other player near to him will not hear any
- CfgWeapons → bipod_01_F_snd → ItemInfo → soundBipodXYZ
- soundBipodDown
- soundBipodUp
audible distance is 20 meters, no matter how close other player near to bipod-deploy player will not be able hear sound
see this YT video (sound source is client next to right side)