Revealing that the creative demands of the long-running public radio program take a substantial toll, Ira Glass told reporters Thursday that he was exhausted from single-handedly doing all the voices for each episode of This American Life. Glass, who has personally recorded the vocal tracks for every reporter, essayist, and interviewee character since the show debuted in 1995, confirmed that after 539 episodes, the labor-intensive process leaves him feeling fatigued and mentally drained by the end of each weeks broadcast. I have to say, I still love doing the program, and I embrace the challenge of creating different kinds of stories populated by interesting and unusual characters, but that undertaking can definitely wear you out, said Glass, who sipped from a mug of honey-lemon tea while recalling the long 18- to 20-hour days spent alone in the recording studio. Just to be clear, theres nothing more rewarding than coming up with all these new characters every week. I delve in, play around with my voice, and experiment with a dialect or fine-tune a cadence until I capture exactly what, for example, a superior court judge or 12-year-old sleepaway camper should sound like. The emotional investment involved in performing as an African-American schoolteacher struggling with budget cuts or a grown woman just learning she was switched at birth can be extremely taxing, said Glass. You have to go into that space and inhabit that character all day long. Im usually dead tired by the end of the week, but theres a satisfactionfulfillment, reallywhen I turn on the radio and hear all of my voices in a completed show. Despite the onerous workload and threat of burnout, Glass said that he is still driven to build out a new fictional world each week filled with the ambitious journalists, Jeep dealership salespeople, sage panhandlers, deceitful children, aircraft carrier personnel, FBI informants, self-conscious lucha libre wrestlers, former hostages, and overly divulging fathers that are beloved by fans of This American Life. Glass told reporters that, several years ago, he challenged himself to create as many fleshed-out characters as possible in the episode 20 Acts In 60 Minutes, noting that he spent several weeks alone writing and recording an emotional song of apology performed by a few dozen teenage girls at a detention center, all of whom were meticulously voiced by Glass. I set aside a considerable amount of time to build a character, perfecting the vocal qualities, and figuring out what makes them tick, Glass said. Back in 1992, before This American Life, when I was working on the Chicago Public Radio program The Wild Room, I was tinkering around with a new voice that had a hint of a Southern drawl and a slight lisp. But it wasnt until I raised the pitch, modified the inflection, added a self-deprecating delivery, and devised a background about growing up in a large Greek family in North Carolina that I had this great, urbane humorist character. And thats how David Sedaris was born, Glass added. Glass, who never digitally alters his vocal performances, relies on time-consuming manual techniques to shape the sounds on his program, such as speaking into a Styrofoam cup to mimic the degraded sound quality of a secret tape recording for a recent segment on the relationship between Wall Street bankers and federal regulators. Moreover, Glass said he taught himself a significant amount of Cantonese to accurately portray the characters he had scripted for the episode Mr. Daisey And The Apple Factory. Though Glass records most of the characters separately and then edits the tracks together later, the 55-year-old confirmed that he tapes some interviews in real time, rapidly switching back and forth between two or more characters. The This American Life creator said that the task was easiest with well-worn recurring characters, like producer Nancy Updike. Doing all the voices for interviews is certainly challenging from a physical standpoint, but nothing like having to create an entire crowd, Glass said. For the Harper High episodes last year, I came up with 352 different high school student characters. Those were particularly tough to recordI barely got through them. I lost my voice for two weeks after creating that pep rally. I actually conceived this lovable freshman named Spud for that show who I really liked who I ended up having to cut in editing, he added. Hopefully I can bring him back for a story on navigating through the peculiarities of adolescence or maybe mother-son relationships. Adding to his exhaustion each week, Glass said hell often head into an adjacent studio to record and mix some plaintive tremolo guitar tracks for in between acts, followed by several hours in a foley studio where he might use a metal rake to produce the sound of a chain-link fence creaking or press down on a leather bag filled with corn starch to mimic the crunch of snow underfoot. Its certainly a lot of work, and I rarely get enough sleep, but I wouldnt still be doing it after 19 years if I didnt love it, he said. The hardest part is that I dont even know who the real Ira Glass is anymore. 