| Frequency | |
| Frequency modulation in its simplest form involves The repetition rate of some periodic vibration pattern, usually described in terms of repetitions per second. | 
If, for example, we say that a musical tone has a frequency of 300 hertz, this indicates that the waveform repeats itself 300 times each second. Frequency is inversely related period as given in the following equation: |
| In the example above the frequency of the signal can be determined from the two measurements given: |
| The discrete frequencies that make up a complex timbre can be found using Fourier analysis. | Frequency is correlated with the subjective sensation of pitch. |