Wow, that’s so cool! I didn’t actually realise that there are no other videos of this type of siren on YouTube, which surprises me a bit given the way they sound!
To be fair, there's a few videos out there - one of mine included - of an ES doing hi-lo and/or alert, with examples in Port Talbot and Grangemouth both recorded doing the former tone as well.
One video does exist of the new Broadmoor siren doing Wail on its only recorded test (it's tested silently now), but the video isn't the best quality (with all due respect to its producer) as it was filmed from the far side of the site and it was hard to hear for most of it.
