Frequencies, like amplitudes, are often measured on a logarithmic scale, in order to emphasize proportions between them, which usually provide a better description of the relationship between frequencies than do differences between them. The frequency ratio between two musical tones determines the musical interval between them.
The most commonly used logarithmic pitch scale is "MIDI pitch", in which the pitch 69 is assigned to a frequency of 440 cycles per second - the A above middle C. To convert between a MIDI pitch m and a frequency in cycles per second f, apply the Pitch/Frequency Conversion formulas:
Middle C, corresponding to MIDI pitch m=60, comes to f=261.626 cycles per second.
(Source: Miller Puckette, The Theory and Technique of Electronic Music. World Scientific Publishing Co. Pte. Ltd. 2007)
The rate of repetition of the cycles of a periodic quantity, such as a sound wave. Thus, frequency is the inverse of the period. More generally, frequency can be thought of as the rate of change of phase. Frequency is denoted by the symbol f, and is measured in hertz (Hz) - formerly called cycles per second (cps or c/s) - kilohertz (kHz), or megahertz (mHz). The only sound which consists of a single frequency is the pure sine tone. All other sounds are complex, consisting of a number of frequencies of greater or lesser intensity. The frequency content of a sound is its spectrum. The subjective sense of frequency is called pitch. That is, frequency is an acoustic variable, whereas pitch is a psychoacoustic one. (Source: Barry Truax - Handbook for Acoustic Ecology CD-ROM Edition. Cambridge Street Publishing, 1999 - CSR-CDR 9901)
A technical term that describes Pitch. The higher the frequency of a sound the higher it sounds in pitch.
Frequency is measured in Hertz (Hz). The number of wave cycles per second.
术语顾问/Consultant to terminology