I visited a friend in Dallas in Thanksgiving of that year. At one point, I counted over 50 aircraft visible at night (landing/anti-collision lights on ). We were at one of the malls that is under the approach for DFW. Every 30 seconds a plan passed over head, either for the left or the right runway ( 1 minute separation each runway).

I honestly cannot imagine what it would sound like quiet, but I'm sure _a lot_ of people didn't sleep for the 3 days there was no air traffic.