From Brendan Gregg
This is entertaining and a technically solid job, but at some point you have to stop calling things like this a DoS attack. 44cm distance with over 100dbA acoustic pressure on an exposed HDD is simply not any real life scenario - you can as well smash it with your boot.
You can get ~130 dBA acoustic pressure at 1m with parametric ultrasonic speakers similar to Soundlazer. Your point stands, but we should be aware of the actual attack distance.