Waves of different amplitudes differ in the degree to which the high point (condensation of air) differ in the degree to which the high point (rarefraction of air) of the wave differ from each other. Amplitude is measured by db (decibels) we can hear it as quiet as 1db and a normal conversation between 2 person is around 40-60db. Sound of 130db produces pain: complexity: perceived as the sound"s timbre (pure sounds of those composed of a wide variety of frequencies) Overtones: frequencies higher than the fundamental frequency: fourier analysis when complicated sounds are broken down into simple component. This is used to compress sounds in a computer. The middle ear: the tympanic membrane vibrates and passes the vibration to 3 bones. (known as ossicles, malleu, incus, stapes, each other bone amplifies the wave further through the oval window. The outer hair plays a role in tuning the cochlea through contraction and relaxation.