Hello to all!
I have add some pictures of the old original 1960's Altec Giant Voice Warning System. Huntsville Alabama once had this system installed around 1965 and removed in the early 1990's. Salina Kansas also had this system too. Most of the system has been removed in Salina Kansas, but if you go to Google Map there is still one located at a school on Norton Street. I have attached the picture of the old multi-cell horns. Redstone Arsenal still has their old system but the original Multi-cell Horns have been replaced with smaller round looking speakers, several years ago.
I have a 1965 Altec Giant Voice Warning System catalog that I will scan next weekend and post.
Enjoy,
Allen