Hmm, yeah, unless S&S have designed a new model without the compressed air, I would worry about the noise causing issues with the elephants and their behaviour/stress levels. Wasn't it said that there were fears the noise of Thunder Looper was affecting the breeding patterns of the cows nearby Alton Towers?
Obviously I'm no zoologist, and cows aren't elephants, but I can't imagine sudden loud, irregular 'wooshes' would do wonders for any animal, especially intelligent creatures like Elephants. I'm sure they would have thought this through though... Hopefully. Plus I doubt S&S would ever scrap using compressed air on this model as using it is basically their kink now!