Limiting voice?

Is it possible to create a brush that is invisible that you can walk through, and only allow anyone in the brush to hear what you type or say into a microphone? I know you can create invisible, walkthrough brushes, it’s only the latter part I’m curious about.

Basically I want to create sound proof rooms that only allow anyone within the room to hear any noise that occurs in the room. I would link that to a door so that the effect is disabled when the door is open.

Is this more of a Hammer question or a Lua question?

I think it’s only possible with Lua.

You can use the DSP with your own sound scapes

I guess you could have a trigger brush which is a brush_entity, you define it in Lua and make it muste the voice chat for anyone who isn’t in the brush. I think there’s a trace function of sorts which finds out where the player is in relation to a point.