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It has to be silent(ish)! and and and it should work with reverse-gravity something something :-)
by keyle 8y ago
It has to be silent(ish)! and and and it should work with reverse-gravity something something :-)
- DennisP 8y agoWell it's not antigravity but this sound-blocking tube might help make ducted fans quieter: https://www.fastcompany.com/90316833/scientists-have-discovered-a-shape-that-blocks-all-sound-even-your-co-workers https://www.fastcompany.com/90316833/scientists-have-discove...