First of all I am using GTKRadiant 1.4 and this is a MP map.

I made a building with music and it is completely surrounded is brushes. When I am on the top of the building or near it the sound leaks through the 'walls'.

I am using target_speaker. I know some people use area portal, but I wasn't sure how to set that up since I lost the area portal URL. If it is an area portal I need, do I surround the hold building or just the door? I set up a brush with areaportal on the door, but no luck.

Don't know if it'll solve your problem but here's an areaportal tutorial

http://www.map-center.com/modules.php?name=Forums&file=viewtopic&t=2081)

Thanks, I've just heard others use are portal so it is worth a try.

Woah woah...hold it guys. Area_portal is for structural use only. Like the tutorial says it's for doors and windows. They basically seal off a room or another area from seeing too much geometry. Sound is a whole different ballgame. You can NEVER seal off sound from another room. It's just not possible. You CAN move the speaker farther away. Or make sure you only use one speaker instead of 2 or more. The more you have the louder it will become. Area portals will ONLY work with structural brushes. If you have a room that has detailed walls and a door in it, it wont work.

Ok, thanks. Annoying when it's a small room and everyone out side of it can hear the music.

The Academy map uses area portals to seal of the music from the bar, and it works grandly.

I never really used area portals, but are they used the same as hint brushes?

It is possible to seal sound off. That area has to be completely vised of from the rest of the map though.