A partial is the simple part of a more complex audio harmonic. Each instrument, from a trumpet to a violin, produces it's own unique quality of sound, called "timbre" which the human ear uses to identify it as sounding like a trumpet or like a violin. The timbre of a sound is created by a multitude of simple sine waves (called partials), that combine to form the total complex harmonic, often referred to as the "harmonic series" or "overtone series". This series is based on a fundamental frequency (first partial) with the remaining frequencies (or partials) making up the rest of the harmonics. The first partial is usually the strongest frequency to the ear and defines the pitch of that sound (such as an A note, or a G#). The intensity (or volume) of the remaining partials provide the timbre of the sound.<br>