This should be possible with the release of ArmA3, guys, but I dont think its doable till then. In the meantime there are guns that have silencers built in, just gotta find em.
So is there any reason you couldnt change it so that the bells aren't automatically rung? They could only be rung by players who wanted(for whatever reason) to summon the whole of the zed population in the area. Think of the fun you could have, lol.
Sign me up. Yeah sure maybe not the MOST realistic, but there are plenty of zombies that do this in other mediums/lores, why couldnt ours? Extra thriller for a thrilling game.