The Siren Board

I have a few questions about the sirens in Bemidji, Minnesota. I was looking at storm footage and came across video on the east side of Lake Bemidji with really low pitched EOWS* 612s. Does anyone know if these are that way on purpose, or if their tone cards are going bad? They sound awesome and menacing regardless. That's why I'm so interested.



https://www.youtube.com/watch?v=rESVZiD6zKA

I know two 2001-130s were added in 2015 to cover more area but I think the 612s (the ones that still work) are still used. So, they're probably pretty old. Knowing that, I'm willing to bet the low pitched ones are just aged. Another video, captured the day before the first video, on the west side, has your typical high pitch.



https://www.youtube.com/watch?v=-0iuWgl0u2A

So, why would their six or so 612s that are the same age end up with different tones? Just curious. Anybody know?

From what I remember they have all been replaced with 2001-130's. I think the reason for the different pitches is different battery voltages, which may cause the lower pitch. Not 100% sure about that but I'm pretty sure that's the reason.

We used to go and stay at a resort up there until a couple years ago. The 612 by the airport was still there. I also seen a couple 2001s on the way through town.

Wow those sound way better low pitched!