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Homework Help: Why are low beats more audible than high beats

  1. Jun 7, 2008 #1
    question: "why are beats more audilbe between two consecutive low notes than two consecutive high notes? support your answer with relevant calculations and explanation?"
    we were given some rules first:
    (the formula for a sound wave, h=hz and t=the x value when graphing)

    (2 sin*((2pi*hi )t+(2pi*hii )t)/2)√ócos*((2pi*hi )t-(2pi*hii )t)/2)
    where hi is the frequency of one tone and hii is the frequency of the sequential tone.

    i remembered that 2^(1/12) would be the difference between them and i still need help explaining why

    any help is muchly appreciated
  2. jcsd
  3. Jun 7, 2008 #2


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    Homework Helper

    Hi brandy,

    The difference is 2^(1/12) because they say consecutive notes; for example, think of consecutive keys on a piano. When you go from one C note to the next higher C, you have to cover 12 keys. And when you go from one C to the next C, the frequency doubles. So the frequency at each steps goes up by a factor of 2^(1/12).

    To answer your question, you might think about what is the difference in frequencies between two consecutive low notes, and between two consecutive high notes, since it is the small difference in frequencies that give rise to (regular) beats.
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