Sound

Introduction

Sound is periodic in which the perceived pitch is directly related to the period. A complex tone has two spectral pitches at 1000 Hz and 1200 Hz, derived from the physical frequencies of pure tones. They also have a stack of harmonics in which the perceived pitch is related to the harmonics. Some theories of pitch perception hold that pitch has inherent octave, and therefore is best decomposed into a pitch for a periodic value around the octave, like the note names in western music, and a pitch height, which may be ambiguous, indicating which octave the pitch may be in.

Pitch depends on the sound pressure level of tone having frequencies below 1,000 Hz or above 2,000 Hz. The pitch of lower tone gets lower as sound pressure increases. For instance, a tone of 200 Hz that is very loud will seem to be semitone lower in pitch than if it is just barely audible. The pitch of higher tones gets higher as the sound gets louder.

Properties of Sound

Sound waves are a type of mechanical waves that have the power to stimulate the human ear and generate the sensation of sound. In the study of sound is required to distinguish the physical aspects of the physiological aspects related to the hearing. From a physical point of view the sound shares all the characteristic properties of wave behavior, so it can be described using the concepts of waves. In turn the study of sound serves to improve the understanding of typical phenomena of the waves. From a physiological point of view there is only sound when one ear is able to perceive. The four basic qualities of sound are the height, the duration, the timbre or color and intensity, strength or power.

In liquids and gases, where there are no significant variations in density, acoustic waves are longitudinal in nature, that is, the direction of oscillation of the particles coincides with the direction of movement of waves. In solids, in addition to the longitudinal strain, there is also the elastic shear strain, conditional on the excitation of transverse (shear) waves; in this case, the particles oscillate perpendicular to the direction of propagation. Velocity of longitudinal waves is much greater than the velocity of shear waves.

Pitch

Strict definition reads: "the pitch depends on the oscillation frequency of a vibrating body (string, vocal cords, etc.). The more vibrations, the higher the sound “This definition considers the sound ...