What would you say if you knew your next words might be your last? Who would you call? On 9/11/2001, all at once, hundreds of people were trapped above the impact point. Most of them could contact the outside world only through a phone call. Some of them called their loved ones, but all they heard was the sound of an answering machine.

We wanted to pay them a tribute and make sure their stories will live on in a very intimate way. We made a generative sound-to-design installation turning their last phone calls into a simple visuals of symbolic Twin Towers. Each visual is unique, made with generative code and silkscreen printed. Each voice can be heard only by getting close to the installation.

Designed for the togetherness of the listener and the sound. The voice doesn’t exist without the listener.

Technology is best when invisible. That is why we didn’t want the technology to stand between the sound and the listener.

First of all, we wanted the last phone calls of the 9/11 victims speak for themselves. That is why we wrote a generative code that allowed us to transform the voices into a symbolic Twin Towers. Then we made an interactive installation using tools that create closeness between the victim and the listener.

Hidden in the installation, six custom made, independently powered capacitive sensors were able to sense the proximity of the viewer and re-enact the phone call respectively to the distance of the observer. All that's left is an undisturbed moment between the listener and the voice.

Stephen Mulderry, floor 89: Mum, it’s Stephen, my plane… my building got hit by a plane and right now… I think I’m ok, I’m safe now but it’s smoky. I just wanted to say how much I love you… and I will call you when I’m safe. Ok, mum, bye.

Melissa Harrington Hughes, floor 101: I just wanted to let you know I love you and I’m stuck in this building in New York. There’s lots of smoke and I just wanted you to know I love you always.

Brad Fetchet, floor 89: Hey mom, it’s Brad. Just wanted to call, let you know, I’m sure that you’ve heard that a plane crashed into World Trade Center One. We’re fine, we’re at World Trade Center Two, I’m a… obviously alive and well over here, but a… obviously a pretty scary experience. I saw a guy fall out of probably ninety first storey, all the way down, so… You’re welcome to give me a call here, I think we’ll be here all day but a… give a call back later, love you.

Brian Nunez, floor 104: (answering machine: First saved message) Hey, it’s Brian, a plain crashes into the Trade Center. It’s on fire and I’m in it, and I can’t breathe. Tell everyone I love them, and if I don’t get out… goodbye. (answering machine: End of message)

Jim Gartenberg, floor 86: “There’s a fire. I love you, tell Nicole ‘I love you’. I don’t know if I’m going to be OK. I love you so much.”

Kevin Cosgrove, floor 105: You got lots of people up here. 9-1-1: I understand, Sir. KC: Smoke raises too, we are on the floor. We are in the window. I can barely breathe now, I can’t see. 9-1-1: Ok, just try to hang in there. I’m going to stay with you. KC: It’s really bad. It’s black, it’s arid. We’re young man, we’re not ready to die. 9-1-1: I understand… Hello? KC: Hello? We’re looking in… we’re overlooking the Financial Center. Three of us. Two broken windows… (the sound of a falling South Tower).