This causes any sound within the sector to have an echo effect.
Place an M[HearingDistance,1000+EchoAmount]
in any sector which does not
have a Lo-Tag (although there are some exceptions). For
HearingDistance, a value of 1024 is equal to the largest grid square in
Build. For EchoAmount, you can use any value between 0-255 (0 being the
least amount of echo).