667 Test of GIANT VOICE system in DC! (twitter.com) posted 3 years ago by Stinky_Stork 3 years ago by Stinky_Stork +670 / -3 87 comments share 87 comments share save hide report block hide replies
I think you are right here, Giant Voice is a global comms system for when the internet is down at times of crisis and war, this was just a speaker test of the DC Police system.
Its says so in the first few sentences.
Giant Voice is litterally a big speaker system, Sauce: https://www.fedsig.com/outdoor-sirens-and-speakers