I'm sure it's copying some kind of hospital sound effect, like an old-tech intercom tone or a warning buzzer, but I just cannot fucking place it. I know I know this sound.
It's driving me nuts. Can someone please tell me what it is? Bonus points if you can link to a recording.
I know about Teardrop. I'm talking about the European version, the third one in the linked video - and specifically about one effect they're using in it.
Sounds like a buzz and a sine wave mixed and lots of reverb. It reminds me of a flute. The truth is that a lot of these sounds are usually synthesized, it is the signature style of Massive Attack. As a result it shares a lot of similarities with the kind of simple analog sound makers used in hospital equipment. It doesn't sound sampled to me, at least, but I could be wrong, it has a lots of things layered on top to say for sure. If anything, it reminds me of the stereotypical code blue alert used in drama shows. Though I have never encountered such a thing in real life, usually those things are communicated verbally without any sort of alarm. Hospitals actually avoid alarming or excitedly modes of operation, preferring calm and collected action.