synthesised siren (loop a bit)
looped bits of freesound #172510 , last take is a bit Kenneth Williams :¬)
Generated with oscillator and (or) modified (processed) sample.
KONICHIWA! Free SE from Japan http://taira-komori.jpn.org/freesounden.html
Can't remember how I did this, but enjoy. It contains the "C" notes spanning some 7 octaves. The individual notes ...
sweeps a bit like syndrum, sounds better when downloaded.