Pitch and Frequecy

When an object, such as a tuning fork or particles in the air, vibrates, a sound wave is created. The frequency of this sound wave is how often the particles vibrate as the wave travels. This frequency is measured in Hertz, where one Hertz is equal to one vibration per second. When these vibrations in the air hit the human ear, they are processed and transmitted via auditory nerves.

  • Frequency
    • All particles disturbed by a sound wave vibrate at the same frequency, because each particle is bumping the next causing it to move.
    • The human ear can detect sound waves with frequencies from 20 Hz to 20 KHz
    • “The sensation of a frequency is commonly referred to as the pitch of a sound.”
    • Most people can tell when two sounds have different frequencies greater than 7 Hz because of the interference and superposition of the two waves.
    • The first audio sample of Dr. Lau’s guitar is tuned to use the E2, A2, D3, G3, B3, and E4 notes or “standard” guitar tuning with frequencies (82.41, 110.00, 146.83, 196.00, 246.94, 329.63) in Hertz.
  • Pitch = human ear’s perception of frequency of a sound vibration
    • High pitch corresponds to high sound and vice versa.
    • “Certain sound waves when played (and heard) simultaneously will produce a particularly pleasant sensation when heard are said to be consonant.”
    • low pitch = low frequency
    • high pitch = high frequency
    • Units of subjective pitch = megs
    • Frequency/pitch relationship is non-linear
    • Pitch changes as loudness increases



Brainstorming Session: Guidelines

  1. Group members must attend every meeting, unless they have an academic commitment. If a group member is unable to attend, they must let the group know via GroupMe as soon as possible.
  2. Group will meet every Tuesday at 3:20 PM to work on the project. The number of meetings per week may increase as the project deadline approaches.
  3. The group will update their progress 1 – 2 times a week on Storify. Group members will take turns documenting the progress.
  4. The group will specifically outline roles and expectations of each member by the next meeting.
  5. The group currently plans to take the Arduino approach, using a microphone to detect the sound, code to determine the frequency and note, and seven segment display to display the note.

The guidelines were written by all group members.