Decided to just record my fridge that i needed for a project, sharing here for anyone else who needs a fridge!. Recorded with a zoom f6, 2 x rode nt55s set to cardioid, xy coincident recording24 bit, 96 khz.
This is a recording of a natural gas furnace for a home air heating system. Rode k2 microphone pointed at the piolet light of the furnace about 3 inches away.
My daughter made an instrument some years ago. She took a small cardboard box and fixed some rubberbands with scotch on it, and this is how it sounded. She called it spelatronics. It no longer exists, unfortunately. But it can be remade.