i learned that the new Rolls-Royce Ghost soundproofing was so over engineered that occupants in the car found the near-total silence disorienting, and some felt sick. Acoustic engineers had to go back and work on "harmonizing" various sounds in the car to add a continuous soft whisper (x)
i learned that the prototype of the Rolls Royce Ghost was so quiet inside that it made test drivers sick. The engineers had to remove some of the noise isolating material, and create seats that vibrated at specific frequencies to introduce some noise into the interior (x)