Sending messages to groups of actors

[Builder Bob]

When removing a Zealot from the game, a sound actor by the name Zealot Death (Unnamed) is created. It will start making some sound, and then stop. I'd like to create the Zealot and remove it without it making any sound. Nobody should even know it was there.

I was able to do this by adding an alias (_DeathModel) to the actor, and then sending the following message:
works:

Actor - Send message "SoundSetMuted 1 0" to actor ("_DeathModel" actor from the scope (Actor scope for Zealot [16.11, 36.91]))

Even though I managed to do what I wanted, I want to extend this to work for any sound actors created for units when they die. Here's some code I hoped would be sent to all actors created by the unit. Unfortunately it doesn't work.
doesn't work:

Actor - Send actor message "SoundSetMuted 1 0" to all actors contained by actor region (Actor for Zealot [16.11, 36.91])

Does anyone know what I have to do to send this message to all actors created for the unit?

Edit - Solved it: The Action I needed was: Send Actor Message to Scope. I just didn't see it before.

Actor - Send actor message "SoundSetMuted 1 0" to all actors in actor scope (Actor scope for Zealot [15.68, 35.92])