Audio Spectrum

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Audio/Audio Spectrum

Outputs the amplitude of the frequencies of a sound. ​


The Audio Spectrum box transforms an AudioLine into an Audio Spectrum by computing a frequency analysis. The Audio Spectrum outputs the repartition of the sound frequency and the amplitude of each frequency. When the box is selected, the Preview Window shows the outputted Spectrum values.

General Use Case: The Audio Spectrum is used with the Spectrum Band Filter. The Audio Spectrum generates the full sound spectrum and allows adjustment. The Spectrum Band Filter selects a range of frequency to output the average gain value. Together, both boxes allow creating an interaction based on sound. Multiple Spectrum Band Filter boxes may be connected in a row in order to optimize the process.

Note: The Spectrum Band Filter and the Audio Spectrum boxes need a Sound Device or a Sound Card set in the System Configuration.


Audio Audio Line Receives the Audio Line to process.


Spectrum Audio Spectrum Outputs the sound spectrum of the received Audio Line.



Output Scale String Chooses the scale of the outputted spectrum between the Linear or the Logarithmic scale. Using Linear reduce the noise, while the Logarithmic scale gives more precision for low levels.
Logarithmic Clamp Float Defines the maximum value of the logarithmic spectrum normalization.
Chop Off Bias Float Sets the value subtracted to the gain value of each sample. Note that the Chop Off Bias is adjusted for the Logarithmic Scale. When using the Linear Scale, the Chop Off Bias must be near zero.
Gain Float Multiplies with the gain of each sample.
Temporal Filter Float Sets the temporal filter smoothing the variation in the outputted values. A value of zero removes the Temporal Filter.

See Also

Boxes related

Audio Line In, Audio Out, Audio Player, Spectrum Band Filter, ​​

Version Information

Current documentation version: 2.1.1. ​ ​