Chapter 4 The World Was Once Analog

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Chapter 4 - The World Was Once Analog

• Introduction
• Sound, Vibrations, And Analog Recording
  (phonograph record) - An analog device maintains
  an exact physical analog of information. For
  example, bumps on an early phonograph recording
  correspond to vibrations that we perceive as
  sound.
• Analog Electronic Devices - An electronic device
  is analog if the amount of electrical current it
  generates is proportional to its input. -
  cassette tape player
• Many Electronic Devices Are Analog - At one time,
  most electronic devices used analog techniques to
  store, amplify, or emit pictures or sounds -
  AM/FM radios, stereos, televisions

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Chapter 4 - The World Was Once Analog

• The First Analog Communication - Early
  telephones used an analog scheme to send voice
  from one place to another the amount of
  electrical current sent between two telephones
  was proportional to the volume of sound
• Analog Is Simple But Inaccurate - An analog
  device always distorts the input and adds noise.
• Sending An Analog Signal Across A Wire
  signal loss - attenuation
• Digital Music - A technology is digital if
  it uses numbers to record information instead of
  a physical analog like bumps on a record or
  magnetism on a tape
• The Digital Revolution transistor - ICs
  

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Chapter 4 - The World Was Once Analog

• Computers Are Digital Inside a computer, all
  information is represented by numbers
• Digital Recording
• Using Digital To Recreate Analog A-to-D
  converter
• Why Digital Music?
• Summary
• Information, including audio and video, can be
  encoded in digital form
• The chief advantage of using a digital
  representation arises because the information
  does not become distorted while being stored,
  copied, or communicated