Yamaha DX7 II FD Reference Manual page 5

Introduction
The process ofFM synthesis involves the modulation of one oscillator's frequency with
the signal from another oscillator. In the DX7 II, oscillators are known as operators. Those
operators which actually produce an audio output are called carriers. Operators which
modulate the frequency of other operators are called modulators. The overall sound which
results from combining carriers and modulators depends on many factors, including the
specific combination of operators. Another important factor is the output level of each
carrier (which affects the volume ofthe sound) and each modulator (which affects the
timbre of the sound).
The DX7 II incorporates two sound modules, each consisting of six operators. The
operators in each sound module can
be
combined into 32 different configurations of
carriers and modulators. These configurations, known as algorithms, are depicted on the
front panel of the DX7 II. They determine which operators will act as carriers or
modulators, as well as their specific combination. In the diagrams shown on the front
panel, the operators in the lowest row are carriers. Those appearing above the carriers are
modulators. The lines connecting the operators indicate the signal paths.
The parameters described in the following pages are accessed by pressing the appropriate
button on the front panel. Some buttons display their parameters in several LCD "screens"
which are selected by pressing the button repeatedly until the desired screen is displayed.
The parameter to be edited is selected by positioning the cursor with the cursor keys. The
parameter value is changed using the
-11+
1 keys or the data entry slider.
-2-