A:Answer First off,
there is no white noise in the active noise cancelling, no hissing or annoying static beep. It's just Plain silence. These are the best noise cancelling headphones on the market as of right now (August 2018).
Second,
It does a very good job actively cancelling the noise out to sudden abrupt loud noises. Idk about thunder or guns but I know a loud Harley came riding past my house and It cut the noise out by 85% and I barely noticed it. It cuts out my fish tank noise from the water falling out of my filter. And those are high tones. It completely cuts out my box fan and cuts out my loud air conditioner by 95%. I barely hear anything outside of these headphones. They really are worth getting.