Yamaha DX7 II FD User manual

YAMAHA
Voicing Parameter
Reference Guide
I
lru·FC>/D
DIGITAL PROGRAMMABLE ALGORITHM SYNTHESIZER
SUPPLEMENTAL BOOKLET

Welcome-----------.,
This is the first in a series of booklets designed to provide a practical guide to creating
your own sounds on the DX7 II. It describes all of the voice and performance parameters,
the range of their values, and the general effect each one has on the final sound. The
parameters are not presented in the order of their physical layout on the front panel.
Instead, they are presented in the order most conducive to understanding FM synthesis.
Section 1 provides a brief introduction to FM synthesis on the DX7 II.
Section 2 describes the basic voice parameters, which determine the actual timbre of each
voice.
Section 3 describes the voice effect parameters, which determine the keyboard and
controller configuration of each voice.
Section 4 describes the performance parameters, which determine such things as the
combination of different voices and the microtuning they will reflect
For continuing information concerning the DX7 II FD!D, consult AfterTouch, the official
publication of the Yamaha Users Group. Many advanced functions will be discussed in its
pages in the coming months. There will also be information regarding the availability of
other materials concerning more advanced applications. To receive a free copy of
AfterTouch every month, send your request to AfterTouch, P.O. Box 7938, Northridge,
CA 91327-7938. On your letter or postcard, be sure to indicate that you are the owner of
a DX7 II FD/D.

Contents
1 Section 1: Introduction
3 Section 2: Basic Voice Parameters
4
Algorithm Button (#7)
6 Output Level Button (#10) Part 1
6
Oscillator Button (#8)
8
EG Button (#9)
11 Pitch EG Button (#13)
13
LFO Button (#12)
16 Sensitivity Button (#11)
17
Output Level Button (#10) Part 2
20
Using the EG COPY Button
21
Section 3: Voice Effect Parameters
22
About Voice Effect Parameters
22
Key Mode Button (#23)
23
Pitch Bend I Portamento Button (#24)
26
BC!MW/AT Button (#25)
29
FC1/FC2 Button (#26)
31
Section 4: Performance Parameters
32
About Performance Parameters
32 Voice Mode Button (#28)
35
Pan Button (#30)
38 FS/CS Button (#27)
40
Micro Tune Button (#29)

Introduction
The DX7 II is a digital synthesizer capable of producing an almost infinite variety of
sounds using a technique of synthesis known as FM (Frequency Modulation).
- 1-

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-

Basic Voice Parameters
The basic voice parameters are used to shape the overall character ofa voice. They are
adjusted in the voice edit mode. This mode is entered by pressing one of the VOICE
MODE SELECT buttons from the play mode, selecting the AorB voice with the AlB key,
and pressing the EDIT button. The parameters described below are then accessed by
pressing the appropriate button.
-3-

Algorithm
Button (#7)
Algorithms form the foundation of FM synthesis. They determine which operators will
act as carriers and modulators, the specific arrangement of operators, and the feedback
path (described below). The following diagram represents Algorithm 1, and illustrates the
various parts of any algorithm.
r···;~;~~~;-~-h~;-··1
[ ___ ~esdback loop \
1st Stack 2nd Stack
1 modulator 3 modulators
The Algorithm button (#7) provides access to the following parameters in a single LCD
display.
Alg The Alg (algorithm) parameter selects the algorithm to be used in a voice.
1 Algorithm 1
32
Algorithm 32
Algorithms determine the way in which the operators are combined as carriers and
modulators. This has a fundamental impact on the types of sounds each algorithm can
produce. For example, algorithm 17 creates good flute sounds, and algorithm 32 produces
very good organ sounds.
Fbi Each of the 32 algorithms has one feedback path. The output of one operator (usually a
modulator) is directed back to its own or its modulator's input. The Fbi (feedback level)
parameter adjusts the level of the signal returning along the feedback path.
0 No feedback
7 Maximum feedback
The effect of this self-modulation is not unlike that of modulation by another operator. It
is often applied to string and brass sounds, as well as noise sounds with high level
settings.
-4-

Osc.sync
Transpose
Voice name
Each DX7 II operator produces a sine wave. The Osc.sync (oscillator synchronization)
parameter determines whether or not the sine waves all begin at phase 0. If they do, the
timbre of a voice will evolve in the same way each time a key is pressed.
off Do not start operators' sine waves at phase 0 for each keypress.
on Start operators' sine waves at phase 0 for each keypress.
The following diagram illustrates the effect of this parameter.
:::-· ...... ..
etc. etc.
If this parameter is off, the tonal transition will be smoother between notes played legato
and more abrupt between notes played staccato. This is often effective for acoustic
instruments.
Normally, the pitch of the DX7 II keyboard is set so that the key marked with the small
triangle corresponds to middle C (C3) with a frequency of 262 Hz. The transpose
parameter allows you to shift the pitch of this key (and thus the entire keyboard) for any
voice by half steps to as much as two octaves above or below the standard pitch.
C1 Assign the pitch Cl to the marked key.
C5 Assign the pitch C5 to the marked key.
This parameter is useful for adapting the keyboard range to suit the voice. For example, a
flute or piccolo patch would be well served by transposing the keyboard pitch up. A bass
sound would need a downward transposition.
This parameter lets you name the voice you are editing with up to ten symbols. The
available symbols (letters, numbers, etc.) are printed in brown below the Data Entry,
Voice Mode Select, EG Copy, Performance, and number buttons.
To enter a name, move the cursor to the voice name parameter and hold down the Edit
button, which has the word "Character" printed below it. While holding the Character
button, enter the desired symbols by pressing the respective buttons. Pressing the Internal
button while holding the Character button will produce lower case letters. The Cartridge
button will produce upper case letters.
-5-

Output Level
Button (#10)
Part 1
The Output Level button (#10) provides access to various level and scaling parameters in
two LCD displays. For the moment, only the level parameter itself will be described. The
other parameters control the level scaling of the voice, and will be described later in this
section.
The level parameter is accessed by selecting the normal scaling mode and pressing the
Output Level button once.
Level This parameter determines the output level (amplitude) of the selected operator.
Oscillator
Button (#8)
Mode
Coarse/Fine
0 Operator's output level is 0 (operator is oft).
99 Operator's output level is at maximum.
This parameter is of fundamental importance to FM synthesis. The output level of a
carrier influences the volume of the overall sound. Remember that carriers are operators
which actually produce an audio signal. A modulator's output level influences the timbre
of the overall sound. As the output level of a modulator increases, so do the number and
strength of the harmonics in the sound.
The Oscillator button (#8) provides access to the following parameters in a single LCD
display.
This parameter determines whether or not the pitch of the selected operator will vary as
different keys are pressed.
Ratio Specifies that the selected operator will vary in pitch as different keys are
pressed.
Fi xed Specifies that the pitch of the selected operator will remain unchanged
regardless of the keys being played.
The ratio mode is generally used by carriers to produce different musical notes as
different keys are played. The fixed mode is useful for special effects sounds, and for the
noise component found in many acoustic instrument sounds-such as the breath of a flute
or the plucking of a harpsichord string.
The frequency (pitch) produced by each operator is controlled primarily by the coarse and
fine frequency parameters. The coarse parameter adjusts the pitch of the selected operator
in large increments. The fine parameter performs the same task in small increments. They
are used together to establish a pitch for the selected operator. The coarse parameter's
maximum value is less than the highest possible total frequency value. The fine parameter
is used to increase the total value beyond the maximum coarse value.
-6-

De tune
In fixed mode, the coarse and fine parameters specify the frequency of the operator in
Hertz (Hz). In ratio mode, the frequency of the operator depends on the key being played.
The coarse and fine parameters specify the interval between the operator and the standard
pitch associated with each key. For example, setting the coarse and fine parameters to a
value of 2.00 in ratio mode will cause the operator to sound one octave higher than the
standard pitch level of the keyboard. A setting of 0.50 causes the operator to sound one
octave lower than standard pitch.
Fixed mode values (in Hz)
1. OOOHz Lowest fixed mode value.
1000 Hz Highest coarse value
9772 Hz Highest fixed mode value.
Ratio mode values
0. 50 Operator sounds one octave below standard pitch.
1.00 Operator sounds at standard pitch.
2. 00 Operator sounds one octave above standard pitch.
31.00 Highest coarse value (nearly 5 octaves above standard pitch).
61. 69 Highest ration mode value (nearly 6 octaves above standard pitch}.
Remember that doubling the coarse and fine parameter values raises the pitch of the
operator by one octave. In ratio mode, octaves below and above the standard pitch are
obtained at values of 0.50, 1.00, 2.00, 4.00, 8.00, and so on. The ratio value forming a
fifth with the standard pitch is obtained at 1.50 and the ratio value forming a third with the
standard pitch is obtained at 1.25.
The detune parameter provides a "super fine" frequency control for each operator. It is
used to shift the frequency of an operator by as much as 2 cents up or down (1 cent =
1/lOOth of a semitone). This parameter is independent of the coarse and fine parameters.
-7 Shift operator frequency down 2 cents.
0 Do not shift operator frequency.
+7 Shift operator frequency up 2 cents.
-7-