Researchers created sound that can bend itself through space, reaching only your ear in a crowd
By combining ultrasound with a concept called nonlinear acoustics, you can create sound that stays silent until it reaches a ...
来自MSN9 个月
Scientists debunk the theory that singers 'whistle' to hit high notes
Low frequency sounds are at the lower limit ofnormal human ... The authors write 'the commonly used term 'whistle register' does not reflect the physical principle of a whistle with regard to ...