Roland Alpha Juno-2 - Tone Color Parameters Oo; Synthesizer Structure

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7. Tone Color Parameters
A tone color consists of various parameters, there-
fore, to edit a tone color, change the values of
those parameters.
a. Synthesizer Structure
The a JUNO’s synthesizer section consists of
several blocks as shown in the picture. Each
block of the synthesizer section is controlled by
relevant tone-color parameters.
®
DCO Block
Modulation Pitch
Lever Bender
©
LFO
Block
@ DCO (Digitally Controlled Oscillator)
DCO is the digitally controlled oscillator that con-
trols the pitch and generates the waveforms that
are the sound source of the synthesizer.
@® HPF (High Pass Filter)
The HPF (High-Pass Filter) is a filter that passes
high frequency harmonics and cuts off the lower
ones. This changes the waveform and controls the
tone color.
@ VCF (Voltage Controlled Filter)
Each VCF lets lower frequency harmonics of the
input signal pass and cuts off the higher ones. In
other words, it is a usual low pass filter. By con-
trolling the cutoff point and resonance, the
waveform changes, thereby the tone color alters.
R
@ 1G)
VCF Block VCA Block
Keyboard
mae Audio Signal
-— Control Signal
@ VCA (Voltage Controlled Amplifier)
After filtered in the VCF, the signal is fed to the
VCA where the volume (amplitude) of the sound is
controlled.
@® CHORUS
@© LFO (Low Frequency Oscillator)
This oscillator generates extremely low frequency,
so produces a vibrato or growl effect by control-
ling the DCO or VCF.
@ ENV (Envelope Generator)
This generates the control voltage (Envelope)
which controls the DCO, VCF and VCA, therefore,
alters the pitch, tone color and volume in each
note.