Transcript Slide 1
Violin Viola Cello String Bass Piano Lute String Instruments Dulcimer Banjo Guitar How does a String Make a Sound? • When a string is made to vibrate by rubbing or plucking, it communicates a frequency to the surrounding air. When these vibrations reach the tympanum (eardrum), they are perceived as sound. Without a medium (air or water), sound cannot be propagated. • Rubber Band Shoe Box Demonstration What is Resonance • When one object vibrating at the same natural frequency of a second object forces that second object into vibrational motion. • The word resonance comes from Latin and means to "resound" - to sound out together with a loud sound. • Resonance only occurs when the first object is vibrating at the natural frequency of the second object. • Tuning Fork Demo The Overtone Series Fundamental Tone First Harmonic- One Octave Second Harmonic-One Octave + A Fifth Third Harmonic-Two Octaves Fourth Harmonic-Two Octaves + A Third Fifth Harmonic- Two Octaves + Fifth Sixth Harmonic – Two Octaves + Minor7th Seventh Harmonic-Three Octaves If the finger is placed at a whole fraction of the length of the string, the vibration produces a note in harmony with the fundamental note. This principle was discovered by Pythagoras already two thousand years ago. Sympathetic Vibrations • Pythagoras discovered that if one string vibrates with twice the frequency of an identical string, we hear the higher frequency as one octave higher in pitch than the lower frequency • The vibrating systems on most musical instruments are made up of two or more vibrating systems working together to produce sounds loud enough to be heard by the human ear. • Examples of instruments with two or more vibrating systems include the membranes of leather stretched across the tensioning loop of a drumhead, the strings and the sounding board of a piano. • Other examples are the strings and the body of a guitar or violin, or the reed and air column of the air column of the clarinet. • Demo On Piano How Does a String Change Pitch? • Length • Thickness • Tension Violin Viola Violoncello Bass Viol/ Double Bass Middle C Fretted Instruments mandolin citern Bowed psaltry Pedal harp Irish harp Lute harp Celtic harp Keyboard instruments harpsichord clavichord String instruments of other cultures Kotojapan Kora-africa Balalikarussia Sitar-india lute