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Notes on video lecture:
Tones versus Noise
Notes taken by Edward Tanguay on January 26, 2016 (go to class or lectures)
Choose from these words to fill the blanks below:
harmonic, environment, transduce, humans, frequency, consider, rare, snapshot, sound, atmosphere, biology, continuously, static, hearing, sine, absence, plucked, white, spectrum, air, vibration
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categories of            signals
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we                    sound signals using the machinery of the human auditory system
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two extremes
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tonal sound signals
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           noise sound signals
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tonal sound signals
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a sound that repeats systematically and                          over time
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tuning forks are not natural sources of sounds
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you aren't going to find anything in nature that produces a          wave
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harmonic series
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much more relevant to                and music in particular
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e.g. a                string
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you can analyze that time varying signal of a plucked string by looking at its sound                 
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look at the sound spectrum
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a snapshot of the energy that this generated by the plucked string in a brief window of time
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the same thing happens to columns of air in wind instruments
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string 1:
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fixed at both ends
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when plucked, generates modes of vibrations
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these disturb the local                     
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it vibrates at
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full length
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half length
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third length
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fourth length
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and so on
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because of the nature of the wave form
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when you take a                 , you get a spectrum described as a harmonic series
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the natural source of a tonal sound, generated by e.g. a plucked string, a column of air and the reed that disturbs it
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fundamental frequency
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the                    that corresponds to the full length of the string
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the vibration that exerts the greatest disturbance to the atmosphere
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the first vibratory mode of a string or column of       
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the defining freqency of music or vocal tone, or any tone that is being generated in which there are vibrations of a series of modes
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the vibration at half the length
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the second harmonic
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the harmonics go on as long as you want to                  them
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tuning fork
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only generates a single frequency
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no                  series as with the a string
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tuning forks don't exist in the natural                       
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plucked strings and columns of air that produce a harmonic series are also          in the environment
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almost always indicative of animals including              and their way of communicating with each other
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most natural sounds are noisy
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the extremes in the range of human               
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1. sine wave and natural tones
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e.g. animal communication
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systematically repeating at a certain                   
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2. white noise
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all frequencies equally distributed
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e.g. TV or radio             , or water rushing
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most sounds are between these two extremes
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the                of a systematic repetition characteristic of a sine wave
Tones versus Noise