Even though sound cancellation seems like a futuristic idea, a worker at Bell Labs first observed sound cancellation in 1878, and the engineer Henri Coandă patented the idea of sound cancellation due to opposing sound waves in 1930 (Hansen 2). The first patent for any type of noise cancelling technology went to German inventor, Paul Lueg, in 1934 (Elliott 13). He then updated his idea in 1936 by adding in a microphone that measured the sound field, manipulated the sound it heard and gave that data to a different source. Lueg’s ideas were a substantial start, but overall, too simple for the complexities that exist with sound waves. They did lay down a solid foundation that others began to build upon over the years however. Harry Olson and Evert May contributed to the next big addition in active noise control. They published a paper in 1953; their main idea was to have another object absorb the sound, and they envisioned this being used in planes or cars (14). In addition, William Conover was another inventor working in the 1950s. His ideas greatly contrasted to those of Olson and May, as he focused on the amplitude of sound waves while Olson and May had concentrated on general ideas as opposed to the scientific details of waves. By the end of the 1950s, no one had produced a machine that would effectively cancel out sound—not because the inventors did not understand the concepts, but because the necessary technology was too advanced.
After discussing the idea of sending out sound waves to cancel out sound, the following question may arise: why not simply block the sound instead of trying to use opposing sound waves? This is the difference between active noise cancellation and passive control. Passive noise control technology involv...


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...ation when the ratio of cost to effectiveness is measured, so it would be less expensive than trying to muffle the sounds of hundreds of people and machines (Hansen 2).
As a whole, trying to create the machinery that precisely measures sound as it produces an opposing wave is extremely difficult to get exactly right, and this is where the disadvantages lay. For one, it takes many years of education to fully understand the way the sound waves work and how to create an active noise cancelling machine, so the amount of people available to install such is limited, which therefore restricts how far and how quickly the sound cancelling technology will spread (Hansen 7). Without more people understanding how to install an active noise control barrier, the idea cannot be as widespread as other scientific ideas that have many people all over the world capable of applying it.