# Fundamental frequency

### Learn more about Fundamental frequency

The **fundamental tone**, often referred to simply as the **fundamental**, is the lowest frequency in a harmonic series.

The **fundamental frequency** (also called a **fundamental**) of a periodic signal is the inverse of the pitch period length. The pitch period is, in turn, the smallest repeating unit of a signal. One pitch period thus describes the periodic signal completely. The significance of defining the pitch period as the *smallest* repeating unit can be appreciated by noting that two or more concatenated pitch periods form a repeating pattern in the signal. However, the concatenated signal unit obviously contains redundant information.

A 'fundamental bass' is the root note, or lowest note or pitch in a chord or sonority when that chord is in root position or normal form.

In terms of a superposition of sinusoids (for example, fourier series), the fundamental frequency is the lowest frequency sinusoidal in the sum.

To find the fundamental frequency of a sound wave in a tube that has a closed end you will use the equation:

F = V/(4*L)

To find L you will use: L = (gamma)/4

To find (gamma) you will use: (gamma) = V/F

To find the fundamental frequency of a sound wave in a tube that has open ends you will use the equation:

F = V/(2*L)

To find L you will use: L = (gamma)/2

To find (gamma) you will use: (gamma) = V/F

The velocity of a sound wave at different temperatures: V = 343 m/s at 20 degrees celsius ; V = 331 m/s at 0 degrees celsius

WHERE:

F = fundamental Frequency ; L = length of the tube ; V = velocity of the sound wave ; (gamma) = wavelength

## [edit] See also

es:Frecuencia fundamental fr:FrÃ©quence fondamentale nl:Grondtoon (natuurkunde) pt:Fundamental sv:Grundfrekvens