Maybe “Spatial audio” fits my description better than “surround sound”. I wasn’t quite sure whether additional processing is mandatory for realistic ingame sound. Back in the day (long long ago), EAX 4.0 was a huge improvement above direct sound. I guess that has changed, luckily!
Long story short: What I’m looking for is an immersive sound simulation for ingame environments, and I don’t like to lack behind proprietary solutions.