It was so loud. I don't remember the noise from my quake experiences in CA. Mostly then just shaking, even the water in the pool splashing out.
This one was like belly of the beast rumbling out here in the country.
In big earthquakes, you hear the sound before it hits.
I heard the Sylmar earthquake in 1971, it was a 6.8.
A huge roar then the getting smacked around for a bit.
Great description about the noise - I thought there were big military helicopters overhead. We live about 10 miles southwest of Independence, KS, in the country.