Eric Ungar’s Acoustics from A to Z: A – Acoustics
One may be pleasant, one annoys.
How sound’s produced and propagated,
And put to use, attenuated,
And how perception plays its part –
It is part science and part art.
The story is told about George Washington Carver, the famous African American scientist who studied peanuts and developed many uses for them, that as a young man he prayed that God reveal to him the secrets of the universe. Because God replied that “the peanut is more your size,” Dr. Carver focused on a more limited field.
Many of us who work in acoustics also had ambitions to know all about acoustics, but we soon learned that the field is much too diverse. Acoustics, as Ira Dyer of MIT has said, deals with “anything that moves and many things that don’t.” That statement may be a little far-fetched, but it does convey the breadth of this art and science. To get an idea of this breadth one merely needs to look at the Journal of the Acoustical Society of America, for example. The topics covered there range from physics and engineering – aeroacoustics, underwater sound, ultrasonics, transduction, vibration, signal processing – through physiological and psychological acoustics – including speech production and perception, as well as human and animal bioacoustics – to noise effects and noise control, architectural acoustics, music and musical instruments. Many other fields are closely tied to acoustics – sound systems, audiology, acoustic oceanography and ultrasonic instrumentation to name a few. You can undoubtedly think of many others.
Clearly, the science of acoustics is well developed, and research is progressing on many fronts. The news lately has been rife with talk about such things as acoustic microscopy, acoustical refrigerators with no moving mechanical parts, and cochlear implants that enable people that have severely damaged hearing to hear again. Often, however, more than science is needed. In cases involving the noise exposure of communities or work areas, human relations and politics also play major roles. And, the artful application of judgment is usually needed to solve practical problems. Typically, they involve tradeoffs between conflicting requirements.
