Musically gifted engineer hits a high note in voice research
Musically Gifted Engineer Hits a High Note in Voice Research
Ingo R. Titze, Ph.D.
NIDCD-funded voice researcher Ingo R. Titze, Ph.D., grew up with two passions: science and singing. Born in Germany during World War II, he was encouraged by his father to develop the mechanical skills needed to help his country rebuild after the war, while his mother and aunt exposed him to German folk songs, and his older brother—an opera buff—introduced him to arias and duets. Early in his 20s, after receiving a bachelor’s and master’s degree in electrical engineering—the latter with a minor in physics—he began taking singing lessons.
Dr. Titze received his Ph.D. in acoustics from Brigham Young University in 1972 and he has studied the human voice for more than 30 years. He is currently a distinguished professor in the University of Iowa’s Department of Speech Pathology and Audiology and School of Music. He also directs the National Center for Voice and Speech, located at the Denver Center for the Performing Arts and University of Iowa. He is the author of Principles of Voice Production, an introductory text used worldwide, and has published more than 500 articles on voice.
Here are some excerpts from our recent conversation with Dr. Titze.
NIDCD: Your academic background is in electrical engineering and physics, yet most of your career has been dedicated to the study of voice. What led you to make the leap in this direction of research? Was there a turning point for you in your career, or was this always the plan?
Dr. Titze: While I was taking singing lessons in Seattle—I worked for Boeing in the aerospace division—I kept asking questions about the voice to my singing teacher, but I never could get satisfactory answers in terms of the physiology and physics behind the art. One day it just dawned on me—a switch flipped in my brain—and I said, “I have to go and find a place where I can study this instrument, the human voice.” So I found a place at Brigham Young University where a famous man by the name of Harvey Fletcher studied speech and hearing acoustics. He was in semi-retirement but still active. He was known as the father of stereophonic sound from his days at Bell Telephone Laboratories. I said to myself, “That’s where I want to study.” His colleague, Bill Strong, became my long-term mentor; he also studied acoustics and got his degree at MIT. I really learned a lot about the acoustics of singing and speaking at BYU. And there, for the first time, I found that both of my passions could be combined into one. This turned into a lifelong experience with voice. To this day, I jump out of bed in the mornings to ask new questions and satisfy my curiosities about this marvelous instrument.
NIDCD: How has the study of engineering and physics helped you in your study of voice?
Dr. Titze: In 1976 I went to Gallaudet University, where I had my first laboratory and got my first NIH grant. The study was about the physics and physiology of voice production, with the idea of developing new techniques to help people who are deaf or hard-of-hearing with their speech. It was a tremendous match with my skills and the problems I was thinking about because voice is so comprehensive in its application of basic physical principles. I worked on aerodynamics in the airways system; movement of tissue, or biomechanics; and movement of waves in solids and gases. Because my Ph.D. was in acoustics, I found myself immediately tackling problems that no one else in this area of voice and speech had ever tackled. I felt like I had my hand in the cookie jar! [He laughs.]
NIDCD: How has the study of voice advanced since you began more than 30 years ago? In what areas have you seen the most progress, and what do you view as the most promising areas of study today?
Dr. Titze: When I began way back in the ‘70s, almost all of the basic scientists that came into voice and speech production got their training in electrical engineering. As I began to develop my line of research and looked at the more current problems, I found that electrical engineering was no longer the master science behind speech and voice production. I felt like I needed to work with mechanical engineers and bioengineers. I started to make friends with researchers in those engineering departments. In the last decade, the focus went to biology—both molecular and cellular biology. Now, I was a complete neophyte. I hated biology [laughing] when I studied toward my undergraduate degree. I never took a biology course as a graduate student and never wanted to have anything to do with biology in the future. All of a sudden, I found that the whole field of human communication was going into molecular and cellular biology; so, I started all over again! Recently I have been studying cells and gene expression, bioreactors, and biomaterials. So, it’s been a long journey—one of retooling many times—but my colleagues and I have not been afraid of that. We enjoy it.
NIDCD: Tell us about Pavarobotti. [Pavarobotti is a voice simulator/singing robot that Dr. Titze designed.] What did you hope to achieve by creating him and how did you go about doing it?
Dr. Titze: In science, you are taught that you do not really know anything until you model it. That’s kind of how I was trained as a physicist. When you can build something to replicate nature, that’s when you really understand it. To study cause and effect, we began with pressure in the lungs, which generates—with the right anatomy—an airflow. With that airflow, we get an oscillation of soft tissues. With that oscillation, we produce pressure disturbances, which create acoustic waves. The waves bounce back and forth in the airways, and finally there is radiation out of the mouth, and that radiation is the sound. Every step along the way, we write physical laws, which are executed in sequence—as cause and effect. At first, one may get some very ugly sounds, and we did. Often the physics were wrong. In the end, however, it became very exciting and satisfying because not only was the sound right, but the physics behind it replicated nature. The beauty was that we never had to begin with sound output from a human and manipulate an already existing sound. I gave the robot the name Pavarobotti to honor Pavarotti the singer, but I never needed any of Pavarotti’s sounds for simulation. I could have made the same sounds if Pavarotti had never made a record. My good colleagues Brad Story and Eric Hunter and I were basically taking guesses at his anatomy, and some of the guesses turned out to be not so good at first. So we guessed a little differently. Fundamentally, it is like baking a cake from scratch rather than following an already known recipe.
NIDCD: What can we learn from Pavarobotti about the study of voice?
Dr. Titze: My dream is that, in my lifetime, we can get a simulator into a therapy room and into a voice studio that can be used for training the best speaking and singing voices. Right now, we have only analysis tools in the examination rooms. But analysis tells you what is, not what could be! A simulator could add a whole new dimension. We would first try to get as close as possible to the client’s or the singer’s own anatomy and voice characteristics. In other words, we would match what the human is presently doing. Then we would predict what changes could take place with intervention. For example, a beginning singer may not have the right vibrato, or the right vocal ring, or enough intensity. We could change parameters in the simulator and say: “Well, if this kind of training could occur, this is what your voice could become.” Likewise, if a surgery were contemplated, the simulator could predict the outcome of the surgery. If someone has a lesion on the vocal folds and it creates a very raspy voice, by virtually removing the lesion, we could tell the surgeon: “This is the likely outcome.”
NIDCD: How close are we to seeing something like that?
Dr. Titze: I have a grant right now called “Simulation of Voice Production in Airwaves.” I hope at the end of the next five years we will have a prototype of a simulator that runs on a laptop—not on big machines with very expensive software that you have to buy for $30,000 or more. It should run on platforms that clinicians can afford and understand. It won’t be the final version, but I think it would be the first prototype that is shareable with the therapy and voice-training community.
NIDCD: You are an accomplished singer yourself. How has your research benefited from your talent? Conversely, how has your singing ability benefited from your research?
Dr. Titze: It is all about asking the right questions. I found that by being a singer myself, I know the troubles singers have. Also, by being in the community of clinicians who deal with voice disorders, I don’t drift away from practical issues. That is one of the benefits of my being in a speech pathology department at the University of Iowa rather than a physics or engineering department at a technological school. I am close to clinicians all of the time and I know what questions are on their minds. Being a singer and a speaker, and trying out new techniques on my own voice first, leads to relevant questions.
NIDCD: The idea of interdisciplinary collaboration is a mainstream concept now, but you have been doing this for more than 30 years. How has your research benefited from such collaborations?
Dr. Titze: At the time I started, I am not sure I could have predicted how popular interdisciplinary research would become. Institutes and centers that transcend traditional departments are now a norm. In voice, we are looking at interdepartmental connections all the time. Many researchers are forced to go across boundaries because they can never amass a strong enough group in one department. At this stage in my career, I have to look even beyond the bounds of a single institution. Professional performing arts centers, for example, provide new venues for data collection, and they are in need of our research product.
NIDCD: According to the American Academy of Otolaryngology–Head and Neck Surgery, World Voice Day “encourages men and women, young and old, to assess their vocal health and take action to improve or maintain good voice habits.” What types of practices can we do to protect our voices?
Dr. Titze: We need a national campaign about healthy voice use. In the last 10 to 15 years of my career, I want to spend much time promoting advocacy for better voice use. This includes teaching people how to pace themselves. Speaking and singing involve exposing one’s tissues to long durations of vibration. The problem is similar to any other exposure problem, like exposure to sun rays. Every person who uses his or her voice extensively has to realize that one cannot vibrate tissue continually without paying a price.
To learn more about how to take care of your voice and tips to prevent voice problems read NIDCD’s fact sheet Taking Care of Your Voice.