The stand-alone mod S.T.A.L.K.E.R. Anomaly aims to be the most stable and customizable experience for fans of the S.T.A.L.K.E.R. games. It's powered by the Monolith 64-bit engine, a custom fork of the X-Ray engine.
Bloodsuckers are a terrifying creature but the combat sounds they make in the Stalker games simply don't stand up to the other creatures. So I fixed it.
I went ahead and replaced most of the Bloodsucker sounds with the sounds of Dying Light's Hunter zombies. In my opinion this is MUCH more fitting for the vampiric monstrosities.
1: unzip file
2: drag gamedata folder into main Stalker Anomaly folder (there should already be a gamedata folder)