10.6

Table Of Contents
307Logic Pro Instruments
Synthesis parameters: Control the polyphonic synthesizer of the EVOC20 PolySynth.
See Logic Pro EVOC20 PolySynth synthesis overview.
Formant Filter parameters: Configure the analysis and synthesis filter banks. See Logic
Pro EVOC20 PolySynth formant filter.
Modulation parameters: Modulate the synthesizer and filter banks—through two LFOs.
See Logic Pro EVOC20 PolySynth modulation.
Output parameters: Configure the output signal of the EVOC20 PolySynth. See Logic
Pro EVOC20 PolySynth output parameters.
Logic Pro EVOC20 PolySynth analysis controls
The parameters in the Sidechain Analysis section control how EVOC 20 PolySynth analyzes
and uses the input signal. Be precise with these parameters to attain the best possible
speech intelligibility and the most accurate tracking.
Sidechain analysis parameters
Attack knob: Determine how quickly each envelope follower—coupled to each analysis
filter band—reacts to rising signal levels. Longer attack times result in a slower tracking
response to transients—level spikes—of the analysis input signal. A long attack time on
percussive input signals—a spoken word or hi-hat part, for example—will translate into a
less articulated vocoder effect. Set the Attack parameter to the lowest possible value to
enhance articulation.
Release knob: Determine how quickly each envelope follower—coupled to each analysis
filter band—reacts to falling signal levels. Longer release times cause the analysis input
signal transients to sustain for a longer period at the vocoder output. A long release
time on percussive input signals—a spoken word or hi-hat part, for example—will
translate into a less articulated vocoder effect. Use of extremely short release times
results in rough, grainy vocoder sounds. Release values of around 8 to 10milliseconds
are useful starting points.
Freeze button: Turn on to hold, or freeze, the current analysis sound spectrum
indefinitely. When Freeze is enabled, the analysis filter bank ignores the input source,
and the Attack and Release knobs have no effect.
Bands field: Drag to set the number of frequency bands (up to 20) used by the filter
banks.