The frequency can also be changed by changing the tension in the string using the tuning pegs: tighter gives higher pitch.On classical guitars, the size change is complicated by a change in density: the low density nylon strings get thicker from the E to B to G then the higher density wire-wound nylon strings get thicker from D to A to E. On steel string guitars, the strings get thicker from high to low. The mass of the string: more massive strings vibrate more slowly.The pitch of a vibrating string depends on four things. To relate notes to frequencies, see Notes and frequencies. (For an introduction to harmonics, see Strings and standing waves. Although the fundamental frequency of the guitar notes do not usually go up into this range, the instrument does output acoustic power in this range, in the higher harmonics of the most of its notes.
Human ears are most sensitive to sounds between 1 and 4 kHz - about two to four octaves above middle C. The orginary guitar can play notes with fundamental frequencies above 1 kHz. The lowest note on the standard guitar is E at about 83 Hz, but a bass guitar can play down to 41 Hz. In guitar music, however, it is normally written an octave higher.) We can hear sounds from about 15 Hz to 20 kHz (1 kHz = 1000 Hz). (The guitar A string plays the A normally written at the bottom of the bass clef. The next A (5th fret on the high E string) is 440 Hz, which is the orchestral tuning A. The A above that (second fret on the G string) is 220 Hz. For example, 110 vibrations per second (110 Hz) is the frequency of vibration of the A string on a guitar. The pitch of a note is almost entirely determined by the frequency: high frequency for high pitch and low for low. The number of vibrations per second is called the frequency which is measured in cycles per second or Hertz (Hz). Ultimately this sound wave causes a very tiny vibration in your eardrum - but that's another story.Īt any point in the air near the source of sound, the molecules are moving backwards and forwards, and the air pressure varies up and down by very small amounts. The disturbance in the air spreads out as a travelling sound wave. Some of this air flows outwards, compressing the next layer of air. When it moves forwards, it compresses the air next to it, which raises its pressure. First, something about sound If you put your finger gently on a loudspeaker you will feel it vibrate - if it is playing a low note loudly you can see it moving.
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