Today, me and fellow user TNT1001 ventured down to Macon to record one of the last two thunderbeams left in service from their old CD system. I believe this video and TNT's video (when he uploads it) to be the first videos of this exact siren. This particular siren is located at Elliott Machine Shops in Southeast Bibb County. You may be able to faintly hear Dry Branch's P-15 at points. I was honestly surprised this siren was even still there let alone active, because I assumed it was replaced already, although satellite imagery from 3/2017 shows the siren is still there
https://www.youtube.com/watch?v=VmkDu2EqMOk
Here are some pictures of the siren for everyone's viewing pleasure. I believe this machine was built in 1985. Sorry in advance if the pictures are massive.