10.6

47Logic Pro Instruments
Logic Pro Alchemy formant filter controls
Source components are shown only in advanced view. Click the Advanced button to switch
to advanced view, then click the A/B/C/D button to select the source you want to edit.
The parameters in this section are shown when the Formant button is active in an additive
or spectral source subpage.
When audio is imported into the additive or spectral engines with the Formant option
enabled, the signal is analyzed and resonances in the original signal are extracted and
converted into a formant filter shape. See Logic Pro Alchemy Import browser.
The formant filter scales the amplitude of additive partials or spectral bins over time to
recreate the characteristic resonances of the instrument, rather than processing the audio
signal like a conventional filter.
Formant filter analyzed parameters
The analyzed controls work only if you enable the Formant button in the Import browser
when importing your audio files. This more detailed analysis attempts to determine the
resonant frequencies of the source audio data.
• On/off button: Enable or disable the analyzed formant section.
• Shift knob: Shift the formant filter up or down in semitones. Higher values can make
sounds seem brighter or thinner. Lower values can create a darker, thicker character.
• KTrack knob: Determine how the formant filter tracks notes on the keyboard. At 100%,
filter resonances shift up or down in pitch with the note. Set to lower values to reduce
key tracking which may make some sounds playable over a wider keyboard range.
• Size knob: Stretch the formant filter to change the perceived size of the resonant
chamber. Use this parameter to alter the size of a guitar body or to make a child’s vocal
sample sound like that of a giant, for example. The Size knob works in conjunction with
the Center parameter.
• Center knob: Set the center frequency for formant stretching (controlled with the Size
knob). Resonances below the center frequency are shifted upward as the Size knob
value is increased. A corresponding downward shift occurs to resonances above the
center frequency.
Note: The Center knob has no effect when the Size knob is set to 100%.
• Smooth knob: Set the rate of change for the formant filter. High values smooth and slow
down formant changes. Low values exaggerate and speed up changes. Low values can
also introduce an unusual “chattering” distortion that may be suitable for drum sounds.