The sound design is made by our foley artist using a rusted iron factory machinery ,mimic a squeaking metallic garage door, that sound extremely unpleasant and disturbing.

Previous researches and many acoustic studies tests dimostrate that painful parts of unpleasant sounds appear to be in the middle range of audible frequencies

and the frequencies responsible for making a sound unpleasant commonly known as offending frequencies, were in the range of 2000 to 4000 Hz.

Usually ,in sound design and music post production sound engineers modify or mask these frequencies in order to make annoying sounds more pleasing to the ears,

but we decided otherwise to emphasize the loudness of metallic screech frequencies to be extremely excruciating,

reaching painful effects and so catch attention of the listener causing a measurable physical reaction that makes many people shudder.