Rod sometimes uses an electronic larynx, a handheld device that sends vibration through the tissue of his throat and up through his mouth, where he articulates sound. He demonstrates: "I am a robot," he quips in most robotic tones.

He is easily understood with "Mr. Robot," but it sounds like a computer is reading aloud. Sometimes, when he's trying to make a phone call, the person hears the buzz and hangs up before he can speak.

Eventually, he opted for a tracheal-esophageal voice, and the surgeon created a passageway in the wall between his remaining trachea and his esophagus.

The surgeon implanted a one-way air valve that lets Rod divert air from his lung into the esophagus. When he gets that air vibrating, it generates a voice, but a quiet one. While vocal folds have many muscles to control characteristics such as pitch and tone quality, the esophagus doesn't. Air pressure and tension in its muscle create sound. Still, Rod, like most who undergo the procedure, quickly learned to maximize what he could with air pressure and muscle tension, and he has some intonation. He also has some pitch, but the colors he achieves now are pastel, rather than his former vivid hues.

He coughs more, because there's an opening straight from his lungs to the world, and the trachea is tender, sensitive and dry. Most people use their noses to warm air to body temperature and moisturize it. Rod breathes it straight in.

Little foam or cloth covers for the stoma trap a little moisture and heat as air moves in and out. He uses a device that provides built-in filtration through a self-closing valve. The prosthesis is inside his neck, and he speaks by diverting air through his lungs and into it. Rod can put his thumb over the stoma, so that the only place air can go as he breathes is through the prosthesis. To inhale, he removes his thumb.

Or he can use a hands-free mechanism that pops into a tube that goes inside the stoma. It's a pressure-sensitive diaphragm that senses when he changes the air pressure in his lungs to speak. When he does that, it unfurls, then folds in on itself again when he inhales.

Rod quickly learned to adjust his pressure because, if there's too much, it won't work. You have to relax as you exhale, Dove says.

If you've ever felt your throat tighten when you're nervous or feeling emotional, you can get an idea of what Rod has had to learn. Anger or strong emotion make it hard to communicate anyway, but when you don't have your native larynx, it's almost impossible. And court is often a tense setting. "He's had to learn to objectify the tension and stay relaxed no matter what," Dove says.