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The science of LOUD sound keeps professor in touch with Def Leppard, car stereos and city laws By
Richard Jenson
Teeth and windows rattle as the car stereo reaches its maximum volume. Sitting in the passenger side of the shaking Nissan 300ZX is a man grinning with two orange fluorescent earplugs sticking out of his ears. He is holding a sound level meter, a small gadget shaped like TV remote-control used for measuring decibels. His eyes light up as the meter continues to register higher. Finally, it peaks at 175 decibels. He turns off the stereo and pulls out and earplugs. "Well . . . that was loud," he says with a smile. Dr. Paul Wheeler is a professor in the electrical engineering department at Utah State University and he is an expert in acoustics, the physics of sound. While still sitting in the car, Wheeler explains that a decibel is a unit of measurement for volume levels. He says the level of volume the car stereo generates is far beyond safe. The threshold of pain for a human ear is around 150 decibels, equivalent to a jet engine at less than 100 feet. Without hearing protection, an eardrum will rupture at around 170 to 175 decibels. "I would definitely recommend hearing protection if this was my car," says Wheeler. Wheeler is testing the volume of the car for a high school student whose father is concerned about his son's hearing. Wheeler is familiar with the concerned parent role; he once sent a sound level meter with his daughter, Andrea Smith, to a Def Leppard rock concert. "He was actually going to go with me," says Smith, "but he backed out at the last minute." Wheeler's concern was that music played at 100 or more decibels for a few hours or more can cause irreversible damage. An average concert, especially indoors, can well exceed 120 decibels. There is no place for the sound to escape and the decibel level is much higher than an outdoor concert. Wheeler ads that this is also true for home stereos and especially for car stereos. The air space is so small that eardrums can easily be blown out with extreme volume levels. "The Def Leppard concert wasn't as high (decibels) as I thought it would have been, it was outdoors, so it wasn't too bad," said Wheeler. When not testing volume levels, Wheeler can be found teaching his students about acoustics. Wheeler teaches classes ranging from the design of complex sound systems to the basics of how sound works. Wheeler's "Sound System Design" class teaches the fundamentals of designing a sound system for an auditorium. Students use formulas to design the most efficient and best sounding system. They must take in to account elements such as air space, walls reflecting sound, and the distance of each seat from the stage. The goal is to have each person attending a performance hear the same sound quality. It is more than just placing and aiming speakers; the math involved is complicated. "With these formulas you can design a great sound system before the building is even built," explains Wheeler. In his "Science and Sound" class, Wheeler teaches his students the principles of what sound is, how it works and how it is created. Wheeler also touches on the importance of hearing protection. Hearing loss is a concern that he says plagues young people more than ever, Wheeler explains. "They don't care about the consequences now, but they will down the line." Hearing loss does not just occur with loud noise, it is a combination of volume and time. Though sudden bursts of sound, such as a gunshot, can quickly cause damage, it is usually high volume over a long period that causes the most damage, explains Wheeler. Wheeler also teaches them about understanding and appreciating sound quality. "There is a lot of bad sound out there. I once had a colleague tell me, 'If bad sound were lethal, it would be the leading cause of death,'" he says, laughing. Wheeler says that many times he is distracted by poor sound quality at performances but looks around and no one else seems to mind. "Many people can't tell the difference," he says. Wheeler also consults on many projects dealing with sound design, quality and efficiency. Sky View High school asked for Wheeler's help with a sound problem in their auditorium. The sound system was having feedback problems with the speakers. Wheeler helped the school position the speakers to stop the feedback and get better sound quality and efficiency. The Logan Police Department has requested Wheeler's services to measure noise pollution for several of its cases. In one case a hotel had some problems with noise bothering the nearby houses. Wheeler went into the neighborhood and took decibel readings from several locations. The volume levels were too high, but when he compared the results with the limits in the Logan city noise ordinance he ran into a problem. "It (the noise ordinance) had some technical mistakes that actually legalized the higher volumes of sound that it intended to stop," explains Wheeler. The police asked Wheeler to rewrite the noise ordinance and correct the mistakes. He was then asked to write the noise ordinances for Wellsville and Cache County. While Wheeler isn't a big Def Leppard fan, he does have a large music collection. "He's a classical man," says Smith, "he has hundreds and hundreds of CD's of classical music." Though Wheeler admits that most of the music he owns is classical, he says he still has some wild CD's. Some of his CD's have sound frequency warnings similar to those on some heavy bass rap CD's. "The warning indicates that the range of sounds may be too great for your speakers or ears to handle at high volumes," says Wheeler. The CD's contain ultra low and high sounds that may blow out speakers or eardrums. When Wheeler isn't listening to music, he is composing his own. His living room is set up as an actual recording studio. He has a piano, an organ, a synthesizer and a full drum set. In the center is a computer where all the music is recorded digitally. He also plays the French horn and a musical saw. "For Christmas he got a musical saw -- that's his new hobby, playing a saw," says Smith smiling. "He likes to write and arrange songs, he's always writing or playing something." Wheeler's love is acoustics, but it was microprocessor systems that he was originally hired to teach at USU. Wheeler started by getting a bachelor's degree at in physics at BYU in 1970. He then got a master's in physics, specializing in acoustics at BYU in 1974. He wanted to get a job in industry or teaching at the community college level, but there was a recession and jobs were scarce. He was told that if he wanted a job he would need to get a degree in engineering. He went back to BYU and received a Ph.D. in electrical engineering in 1978. Though in the electrical engineering department, Wheeler also studied nuclear engineering. He wrote his dissertation in the chemical engineering department, where he did experiments that modeled nuclear reactor fluids. Wheeeler started out in industry as a nuclear engineer at the General Atomic Company in San Diego. After three years in nuclear engineering he switched to electrical engineering, where he taught workers how to use microprocessors. On the side he began teaching evening physics classes at the San Diego Community College. In 1983 Wheeler was hired at USU to teach microprocessors and digital system design. He did not teach acoustics for several more years. Utah State's honors program asked Wheeler to design a class for teaching the physics of sound. Wheeler developed "Science and Sound" and eventually the class became a general education course. The music department then asked him to set up a joint music/engineering minor. "A lot of high school students come in and want to do engineering but also want to do music. This course allows them to do both," he says. Wheeler says he's the same way: "I like music, I like science, and acoustics is what brings together music and science." The course teaches the science of the sound coming from the instruments. The music side of the course is the instrument making the sound, the engineering side explores why and how it sounds the way it does. "For years he has been one of our most popular teachers," says Ron Thurgood, head of the electrical engineering department. "Students like him and look up to him. He's always helping them, giving them advice, helping with projects." His popularity probably has something to do with his sense of humor. "He loves cracking jokes, he's a big punster," says Smith. "He's really corny, he'll just rattle off puns, one after another, and you're like 'ugggghh!' After a while you just have to slap your knee and go 'ha-ha' (sarcastically) to give him the hint to stop." Sound isn't the only thing that interests Wheeler. A waterwheel in front of Wheeler's house hints at a unique hobby. He enjoys visiting and collecting pictures of old mills and waterwheels. He has dozens of pictures of waterwheels at his home and in his office. His web page has a link to SPOOM, the Society for Preservation of Old Mills. He explains how he stumbled upon such a hobby. "One day I said to my wife, 'I need a hobby, what could I collect?' While trying to think of a hobby, his brother-in-law sent him a gift that inspired him. "It was a bath mat with a picture of water wheel on it, and it said 'The Water-Wheelers' on it." His hobby was born. "I looked at the name Water-Wheeler and I thought to myself, well, I'm a Wheeler and I'm all wet. At least that's what my students tell me."
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