CDIS 4313 Lecture Notes - Lecture 4: Sine Wave, Sound, Musical Tone
Document Summary
Wave form graph that visualizes nature and characteristics of sounds: amplitude or intensity (vertical y-axis) as a function of time (horizontal x-axis) Amplitude = degree of displacement; translates to loudness . Pure tone: has one frequency, specific pitch, thin quality, sine wave, very rarely do we hear sounds in our environment that have one single frequency. Complex sounds: a sound wave consisting of two or more frequencies, they combine and interfere with each other, because most sounds we encounter are complex, the sound waves combine and interfere with each other to combine frequencies. Tympanic membrane also vibrates in more complex manner: types of complex sounds. Periodic series of frequencies that are systematically related to each other. Fundamental frequency (fo) lowest frequency of a sound. Harmonics in complex periodic sound are whole-number multiples of fo. Fo = 100 hz; harmonics = 200 hz, 300 hz, 400 hz, etc. Fo = 300 hz; harmonics = 600 hz, 900 hz, 1200 hz, etc.