Today's Lesson

Frequency, in its most pragmatic definition, is the exact number of times, or cycles, the waves of a particular sound move through the air per second. Hertz is the unit of measurement used to identify frequency. One complete cycle that travels in one second is 1 Hertz (Hz).

A low E string on a guitar vibrates at 82 Hz. When plucked, its sound waves complete 82 cycles in one second. Middle C on a piano resonates at 261 Hz. All sounds have a frequency number identifying the exact number of cycles per second. 

Musicians will refer to the notes they play as “pitch” or “pitches”. They use letter names such as, C, Eb, G#, F, Db, and so forth. On the EQ tools used by studio and live sound engineers, these same pitches or notes are referred to in terms of frequency numbers or Hz. So, simply put, frequencies and notes are the exact same thing.

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