Thought:
Use small refrigeration system to chill an a compressed air pressure tank (the kind they use for filling tires or pneumatic tools) below freezing.
Use chilled high pressure air at about 100psi to blow out of some cap tubes pointed at different directions into an electronics box or in my ear.
*Would need to insulate the cap tubes.
*The air would be super dry coming out of freeze tank but might condensate with the box air after it comes out so could not point it directly at the electronics.
*Wrap a coil around some old air compressor tank and insulate it.
*The mass of heavy steel of the air tank might make it hold temp a while.
*The noisy air compressor could be outside.
Might be crazy.
I need to experiment.