This page documents the sources of sounds used by this project.
Used Audacity to make a chirp sound, I think it's Sine-Sawtooth. Pretty easy thing.
A rough analog to an explosion, a work in progress, could be coupled with sounds of trash and debris to make the sound fuller. May fit as an artillery sound effect.
An edited, impactful sound of concrete or the "boulder crashing noise" made from playing with the now demolished bits of rebar, concrete and dangerous refuse near Glasgow, Maxwell Drive. This recording was fairly difficult to attain and required layering, use of EQ to cut out the motorway sound. 2021: Nothing is left of the buildings except the flats are now apartments. So this sample is a bit of history.
Weird alien-like sci-fi alarm noise
The sound is brown noise mixed with the sound of a two engined prop airplane and made seamless.