What I want to know is, how did they get some of the phones to sound exactly like a person coughing?

For those who don't feel like going to the linked site, this concert worked like this: When you arrive, you register your cell phone number at a kiosk, and are given an assigned seat. The computer system then downloads a preset ringtone into your cell phone. The computer then knows the nature and location of each phone's sound, so the composer/performer can create specific sounds in specific locations by having the computer dial specific phone numbers. What I heard of the result was odd, but strangely unpleasant.

Aloha,
Mark