The Formant Filter Node provides pre-configured filters, to mimic various vowel sounds from natural human speech, usable by simply selecting a vowel. You can use this effect, for example, to create rich, choir-like synth sounds.
This effect usually works best with complex audio sources, where there is plenty of audible content left after the filters are applied.
Inputs
Audio
An audio signal to which the effect is applied. This should be a complex (or even noisy) audio signal, with a broad frequency spectrum, so that there is plenty of audio left after the filters have been applied.
Settings
Articulation
Sets which pre-configured group of filters to use, and thus which vowel to mimic.
Sequence mode
In this articulation case, the node uses a custom built sequence of vowels for filtering.
Seq. step duration
Sequence articulation mode only – ★ with AudioNodes HD
Specifies the length of time for each vowel in the sequence.
Seq. transition smooth
Sequence articulation mode only – ★ with AudioNodes HD
Only available in sequence articulation mode. It softens or strengthens the transition between individual vowels. The higher the value, the smoother the transition.
Reset on play
Sequence articulation mode only
When set, sequence will start at the beginning after every playback initiation.
BPM sync
Sequence articulation mode only
When set. vowel steps durations are interpreted as beats.
Outputs
Audio
The audio signal result, with filtering applied. Compared to the input audio signal, the output is often significantly quieter overall. This is because filtering attenuates and removes parts of the audio spectrum, to mimic the selected formant.
You can compensate for this by raising the output signal’s volume, using a Gain Node.