/trigger add beepall print "" "${server}.${channel} =~ fn.#perth" "" "/print -beep"

/script install text_item.py

/set weechat.bar.status.items

use tab completion on above and add ,beepall 

/alias add baoff /set trigger.trigger.beepall.enabled off;/set plugins.var.python.text_item.beepa
ll "";/window refresh;/key bind meta-ctrl-M /mute /baon

/alias add baon /set trigger.trigger.beepall.enabled on;/set plugins.var.python.text_item.beepall
 "all ${color:red}b";/window refresh;/key bind meta-ctrl-M /mute /baoff

/key bind meta-ctrl-M /mute /baoff