Pitch is the characteristic of sound by which the ear assigns it a place in a musical scale. The ear assigns such a place to each musical tone but not to other sounds. When a stretched string is plucked, sound is produced that causes a given pitch sensation. When a glass breaks, we also know by the pitch of that sound that if the glass broke. The principal physical characteristic associated with pitch is the frequency of the sound wave. The range of frequency to which the human ear is sensitive varies considerably with the individual. The average ear manages to hear from 20-20000 Hz. This value was empirically obtained by testing a number of individuals with no hearing defects and in healthy conditions. As one ages, the cap for the frequency decreases. These limits are the extremes of which sound can be heard. However, for speech, the only required frequency range is from 100 to 8000Hz to reproduce with fidelity the sound of the speaker. Perfect fidelity of reproduction would require that the sound wave emitted by the reproducing system be exactly similar to that of the original source, both in frequencies present and in relative amplitudes of the various frequencies. High-fidelity reproduction attempts to approximate this condition.
Relatively recent developments in the recording and reproduction of sound have resulted in high-fidelity reproduction in which the full audio range is reproduced with little distortion. This became possible when electronic engineers fused the art of amplification of minute fluctuating electric currents with modern understanding of acoustics and music. As is the case with standard radios, the old 78-rpm records reproduce a frequency range of 50 to 7500Hz, while high-fidelity records (33 1/3 rpm) reproduce a frequency range of 30 to 1500Hz. There are several factors which must be considered in the production of high-fidelity music such as room acoustics, faithfulness of the original recording, quality of the record player and pickup mechanism.
Posted 2011-01-29 and updated on Jan 29, 2011 8:44pm by crisd