TIMBRE is the tonal quality or color of a sound. This quality is determined by the wave shape, which is determined in turn by factors such as the shape of the vibrating body, its material (metal, wood, human tissue), and the method used to put it in motion (striking, blowing, plucking).
1. Vibrating Stimulus
(Drum Stick, Bow, fingers, pick)
2. Vibrating Body
(Drum Head, String, Metal, Air)
3. Resonator
(Body of Drum, body of violin or guitar)
4. Other
(Snares, guitar distortion, spider-web casing on balafon)
 
Each tone we hear is actually a composite of tones called the harmonic series. The pitches produced simultaneously by the vibrating sections are called partials, overtones, or harmonics.
 
The first partial, often called the fundamental, is the lowest frequency and is perceived as the loudest. This is what the ear identifies as the specific pitch of the musical tone.
 
TIMBRE: CLASSIFYING MUSICAL INSTRUMENTS
IDIOPHONES
 
Instruments made of naturally sonorous materials not needing any additional tension as do strings or drumskins. The basic question is how they are set into vibration.
 
Methods:
 
concussion (struck together)
struck
stamped
shaken
scraped
plucked
rubbed (friction)
 
AEROPHONES
 
Aerophones include what are usually called “wind instruments,” with the addition of a few instruments with a different acoustical principle called free aerophones. There are two essential factors: a tube enclosing a column of air, and a devise for setting that air into vibration.