Adding Sounds To Portal 2 SDK
Scene choreographer? You mean the face poser? You CAN do it that way, but it's hard, and you won't be able to put your map on the workshop or release it as a stand-alone map.
Anyway, just record it in Audacity and save it as a 44100 WAV file.
Will the Audio cache (The one I rebuilt with snd_rebuildaudiocache) stay with the map or will who ever I give it to need to do it too.
The command snd_rebuildaudiocache is slower than snd_updateaudiocache and both are ok for what you are trying to do. In order to automate the command snd_updateaudiocache you can try this:
1. Go to your Portal2/portal2/cfg folder
2. Create an autoexec.cfg (plain) text file if there isn't any
3. Add snd_updateaudiocache in
Now you should embed that autoexec.cfg into the bsp using pakrat along with the custom sound you create. This way, everyone will listen to it with no problem. 
useful tools and stuff here on TWP 
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Actualy, you dont't need to have any autoexec files in your .bsp.and update audiocash at all if you packed your sound files into .bsp. It worked for me and everyone who played my map Hard Light.
Now that you mention it, I remember ChickenMobile saying the same... Thanks for the correction.
useful tools and stuff here on TWP [spoiler]
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