10.6

Table Of Contents
313Logic Pro Instruments
Noise generator parameters
Level knob: Control the amount of noise added to the signals of the two oscillators.
Color knob: Set the timbre of the noise signal. Turn full-left to hear white noise. Turn
full-right to hear blue noise (high-passed noise). White noise has traditionally been
used to create wind and rain sound effects. It has the same energy in each frequency
interval. Blue noise sounds brighter, because its bass portion is suppressed by a
highpass filter.
Tip: Set Color to the full-right position and Level to a very low value to achieve a
lively and fresh synthesis signal.
Logic Pro EVOC20 PolySynth tuning and pitch controls
The parameters at the lower left of the interface control the overall tuning and other pitch-
related aspects of the EVOC20 PolySynth sound.
Tuning and pitch parameters
Tune field: Set the overall tuning in cents. One hundred cents equals one semitone step.
Analog knob: Set the amount of random pitch detuning. Analog simulates the instability
of analog circuitry found in vintage vocoders by randomly altering the pitch of each
note. This behavior is much like that of polyphonic analog synthesizers.
Glide knob: Determine the time it takes for the pitch to slide from one note to another—
portamento. Also see Logic Pro EVOC20 PolySynth global parameters for information
about mono and legato mode.
Bend Range field: Determine the pitch bend modulation range, in semitone steps.
Logic Pro EVOC20 PolySynth filters
The Synthesis section includes a lowpass filter that is used for coarse signal shaping
before the signal is more precisely shaped by the individual bands of the formant filter
banks.