Moog Minimoog User manual

the
minimoog
synthesizer
operation
manual
moog
MUSIC INC.
Academy Street (P.O. Box 131)
Williamsville, NY 14221

A GUIDE TO THE OPERATION OF THE MINI MOOG MODEL D
contents
introduction
basic mini moog features
audio, control, and timing signals
setting up the instrument
output section
oscillator bank
controllers
modulation mix
others
mixer
modifiers
filter and filter contour
loudness contour
accessories
options
s-trigger plug
left-hand controller
tuning procedures
introduction
An electronic music synthesizer is a musical instrument whose circuitry can be intercon-
nected and set up in a large variety of ways to produce a broad spectrum of musical sounds.
The component circuit controls and interconnections of the Mini Moog Synthesizer are ar-
ranged in a logical and convenient way which is ideal for live performance.
The purpose of this manual is to acquaint you with the component circuitry of the Mini Moog
and the operation of each of the controls and switches regulating the generators, modifiers,
and control devices involved in the synthesizing of a musical sound. After proceeding step
by step through the instructions outlined below, you should be ready to begin using your in-
strument creatively and efficiently.

basic mini moog features
The Mini Moog contains the basic components and features to be found on larger, studio-
oriented synthesizers. Its five sound sources include three oscillators for the production of
pitched tones, one noise source for the production of unpitched sounds, and one microphone
preamplifier for the introduction of live signals. Mixer controls are available for balancing
these signals.
Sound modifiers include a lowpass filter and an amplifier, both of which have their own con-
tour generators. The control devices include a 44-note keyboard for use by the right hand,
and two wheel controls and two switches for use by the left hand.
Provision is made at the rear of the instrument for connecting external controlling devices
such as sequencers, foot pedals, and two-dimensional (joystick) controllers. These may be
used to control volume, pitch, and filter characteristic. Timing signals may also be intro-
duced to trigger the contour generators.
audio, control, and timing signals
Sound travels through the Mini Moog circuitry in the form of electrical signals which are
called AUDIO signals. These audio signals are generated by the five sound sources, and after
undergoing extensive modification emerge as the output signal. It is this signal, amplified,
which is translated into sound by your speaker system.
There are two other types of signals which are not heard directly as sound, but instead are
used to influence the way in which the generating and modifying circuitry performs:
CONTROL signals are used to change the pitches of the oscillators, the characteristics
of the filter, and the amount of amplification by the amplifier. These control signals
are responsible for all of the musically significant changes and contours in the musical
sounds produced by the Mini Moog.
TIMING signals come from the keyboard (or from an external source) and are used to
trigger, or start off, the contours which open and close the filter and amplifier. A tim-
ing signal begins whenever a key on the keyboard is depressed, and stops when all
keys are released. Timing signals are used to initiate and terminate musical sounds,
whereas control signals are used to shape and change these sounds while they occur.

setting up the instrument
Place the instrument at a convenient level for playing and secure the Front Panel in the "up"
position by means of the metal bracket underneath.
1. Set all switches in the off position (left-hand or bottom half depressed).
2. Referring to Fig. 1, below, set all of the control knobs as indicated.
3. Plug the power cord into any conventional 117 Volt A.C. outlet.
4. Two 6’ patch-cords are supplied with the Mini Moog. If you are using a portable, guitar-
type amplifier, run the cord with the phone plug at each end from the LOW level MAIN
OUTPUT jack on the rear connector strip of the Mini Moog to an input on your amplifier.
If you are using a monitor amplifier, you will need to use the other cord. Plug the phone
plug end into the HIGH level MAIN OUTPUT jack of the synthesizer, and run the small
phono-plug at the other end into the high level input of the monitor amplifier (or into the
line level input of a tape recorder).
The following sections of this guide will be devoted to a systematic description of individual
control functions in relation to the synthesizer’s component circuits.
Fig. 1

output section
The Output section of the front panel includes two basic switches: the POWER switch, which
turns the instrument on and off, and the MAIN OUTPUT switch, which sends the final audio
signal out the MAIN OUTPUT jacks at the rear and into your amplifier. In addition, there
are volume controls for the MAIN OUTPUT and HEADPHONE signals, and an A-440
switch, all of which will be described below.
1. Turn on the POWER switch (P). The instrument should generally be given about ten
minutes to warm up before tuning and playing. Once warmed up, there is practically no
limit to the length of time it may be kept on and in use.
2. Turn on switches (B) and (C) and the MAIN OUTPUT switch (M). Adjust the volume
control on your amplifier so that, as you play the keyboard, fairly loud tones are heard.
Further adjustments in the overall volume may be made with the MAIN OUTPUT VOL-
UME control (26)
3. Briefly turn on the A-440 switch (Q). This signal will be used for tuning the instrument,
and is not used during actual performance. The tuning procedure will be described in the
controllers section, step 11.
4. A separate output is available for headphones, in addition to the MAIN OUTPUT. For
quiet practice, or for tuning up prior to performance, the MAIN OUTPUT switch may be
turned off, so that the audio signal is not fed into the amplifier. A pair of low impedance
headphones with a stereo plug may be plugged into the jack labelled PHONES (N). The
HEADPHONE VOLUME control (27) is then used to regulate the volume of the head-
phone signal.
Front Panel Diagram
26
27
B
12
13
14
15
16 H
A
1
2 3
17 18 19
20 21 22
23 24 25
J
K
L
P
M
Q
2928
S
R
D
F
E
C
G
CONTROLLERS MODIFIERS OUTPUTMIXER
54
OSCILLATOR BANK
876
9 10 11
N

oscillator bank
This group of circuits contains three separate and independent oscillators. Each oscillator
produces a waveform which repeats regularly, thereby giving rise to a tone of definite pitch.
The audio signal outputs of the three oscillators are activated by turning on mixer switches
(C), (E), and (G). Since switch (C) is now on, we are hearing the output of oscillator 1,
which is the top row of controls (4, 5, and 12).
1. The RANGE switch (4) determines the pitch range in which the oscillator functions.
Press down a key in the middle of the keyboard, and turn the RANGE switch through its
6 positions. You will hear that all positions except the lowest are separated by one octave.
The LO position produces sub-audio clicks which may be used for rhythmic effect. Re-
turn the switch to its 8´ position.
2. The WAVEFORM switch (5) selects one of six waveforms, each of which has a different
overtone spectrum, and therefore produces a different basic tone quality. From left to
right, the available waveforms are: triangular, sawtooth-triangular, sawtooth, square, wide
rectangular, and narrow rectangular. (Oscillator 3 substitutes a reverse sawtooth for the
sawtooth-triangular.)
Hold a key down and run the WAVEFORM switch through its positions, noticing how
the tone quality changes. The triangular waveform has the least harmonic content; the
narrow rectangular has the most. Generally your ear will be your best guide in deciding
which waveform to use for a particular quality.
3. The VOLUME control (12) adjusts the amount of Oscillator 1 signal which is fed to the
mixer, while switch (C) instantly turns the oscillator on or off. Oscillators 2 and 3 may be
heard by turning on switches (E) and (G) respectively, and their relative volumes may be
adjusted with VOLUME controls (13) and (14).
4. FREQUENCY controls (7 and 10) are found only on Oscillators 2 and 3. These controls
raise or lower the pitch of their oscillator by as much as a major sixth with respect to Os-
cillator 1. To hear this, turn on switches (C) and (E), turn off (G), and depress a key. Ad-
just control (7) until the pitches of Oscillators 1 and 2 are nearly in unison. As you move
up and down the keyboard, the pitches of the two oscillators will move together. Now
turn control (7) clockwise while depressing a key, until a perfect fifth is made. Once
again, this interval will remain constant as you play different notes on the keyboard. Any
intervals within the range of the oscillators may be set up simply by setting the RANGE
switches and FREQUENCY controls appropriately.
5. By turning off the OSCILLATOR 3 CONTROL switch (B), Oscillator 3 may be discon-
nected from the control of the keyboard. To observe this, turn off switches (B), (C), and
(E), and turn on switch (G). The pitch of the oscillator will not change as different keys
are struck. You will also observe that Oscillator 3’s FREQUENCY control has a much
wider range when switch (B) is off. If you hold down one key and turn control (10)
through its range, you will hear a frequency sweep of 6 octaves rather than one octave.

controllers
This section will demonstrate the use of the controls located to the left of the Oscillator Bank
(used in tuning and setting up a sound), as well as the keyboard and the manual controls on
the panel to its left (used during performance). All of these controls have an effect on the os-
cillators’ pitches, while the Modulation Mix and keyboard may also be used to control the fil-
ter.
modulation mix
Oscillator 3, unlike Oscillators 1 and 2, is available as a control signal in addition to function-
ing as an audio signal. As a control signal, it may be mixed with the output of the Noise
Source using the MODULATION MIX control (3) and introduced whenever the performer
wishes, using the MODULATION wheel (29). The procedure described below will familiar-
ize you with the use of the Modulation Mix in controlling the pitch of Oscillator 1:
1. Turn off switch (B), so that the pitch of Oscillator 3 is not affected by the keyboard.
2. Turn off switch (G) and turn on switch (C). Now you are hearing Oscillator 1, but not
Oscillator 3, when a key is depressed.
3. Set Oscillator 3’s RANGE switch (9) to the LO position, its FREQUENCY control (10)
to mid (0) position, and its WAVEFORM switch (11) to the triangular (extreme left) set-
ting. This produces a very low frequency triangular waveform which oscillates only a
few times a second.
4. Set the MODULATION MIX control to 0, so that its signal is that of Oscillator 3. Turn
on the OSCILLATOR MODULATION SWITCH (A). This switch directs the Modula-
tion Mix signal to control the oscillators’ pitches.
5. The slowly varying output voltage of Oscillator 3 is now going through the MODULA-
TION wheel (29) at the left of the keyboard, and from there may be applied to periodi-
cally change the oscillators’ pitches (we will hear its effect on Oscillator 1). The MODU-
LATION wheel is in effect a level control for the Modulation Mix. Slowly move the
MODULATION wheel back and forth with your left hand while holding down a key with
your right hand. The position of the Modulation wheel will determine the amount of
variation you hear in the pitch of Oscillator 1.
6. Change the setting of Oscillator 3’s FREQUENCY control and notice the resulting in-
crease and decrease in the speed of the modulation
7. Change the setting of Oscillator 3’s WAVEFORM switch and you will notice the change
in the shape of the modulation. You should actually be able to hear the contours of the
different waveforms − the alternation of high and low tones in the square wave, the re-
peated upward glissandi of the sawtooth, etc.
8. The setting of the MODULATION MIX control determines the proportions of the mix-
ture of Oscillator 3 and Noise Source. As you slowly turn this control clockwise, you will
hear less periodic modulation and more random modulation.

9. Before continuing, defeat the oscillator modulation by turning off switch (A).
other controllers
10. The PITCH wheel (28), located next to the MODULATION wheel to the left of the key-
board, is used to bend the pitch determined by the keyboard (as much as half an octave up
or down) when the performer wishes to introduce expressive nuances to individual notes
during performance. Depress a key, and move the PITCH wheel back and forth with your
left hand. Notice that you can reset the control by feel − a detent mechanism holds it in
its normal center position.
11. The TUNE control (1) is used to tune up the Mini Moog oscillators to the pitch of the en-
semble in which it is being used, or to its A-440 reference tone. Check to see that switch
(C) is on, and notice that, when a key is depressed, the pitch moves up and down by a few
tones as the TUNE control is turned through its range. Make sure the PITCH wheel is in
its center position, and turn on the A-440 switch (Q). Depress an A key on the keyboard,
and adjust the TUNE control so that the two A’s are in tune with each other. Turn off the
A-440. The other two oscillators may now be tuned to Oscillator 1 using their FRE-
QUENCY controls.
12. The GLIDE control (2) regulates the amount of portamento, or glide, heard between
pitches as first one key and then another is depressed. This control is activated by turning
on the GLIDE switch (R). Setting the GLIDE control at various levels, play a scale or ar-
peggio, first with the GLIDE switch on, then using the switch to introduce glide selec-
tively between certain notes only. Notice that the further to the right control (2) is set, the
longer it will take a tone to move from one pitch to the next.
13. Finally, the KEYBOARD itself functions as a controller. It produces a control signal
which varies according to the position of the key struck. If more than one key is held
down, only the lowest one has effect. The control output of the KEYBOARD is perma-
nently connected to Oscillators 1 and 2. Switch (B) couples it to Oscillator 3. Switches
(K) and (L) couple it to the filter, and are discussed in the section titled modifiers, step 8.
The KEYBOARD also produces a timing signal each time a key is depressed. This will
be discussed in the modifiers section in connection with filter and loudness contour con-
trols.

mixer
Audio signals produced by the three oscillators, noise source, and microphone preamplifier
are combined and balanced by the Mixer section’s switches and volume controls. It is this
composite signal, the output of the mixer, which is then modified by the filter and loudness
contour controls and appears as the audio output signal of the Mini Moog.
1. The OSCILLATOR VOLUME controls (12, 13, and 14) are used to regulate the relative
levels of the audio signals produced by the three oscillators. Switches (C), (E), and (G)
instantly turn the individual audio signals on and off. Switch (G) does not affect the con-
trol signal produced by Oscillator 3 via the Modulation Mix. The operation of these con-
trols and switches has been discussed earlier.
2. The EXTERNAL INPUT VOLUME control (15) is connected to a microphone preampli-
fier. The input to this preamplifier is the phone jack on the rear panel labelled EXT. SIG-
NAL INPUT. Any sort of high impedance microphone signal or sound source may be fed
into this input. This includes guitar microphone, voice microphone, wind instrument mi-
crophone, tape recorder output, radio, etc. Control (15) is adjusted so that the OVER-
LOAD light blinks on and off occasionally when loud sounds come through the external
input. Switch (D) feeds this source into the mixer.
3. The NOISE VOLUME control (16) regulates the level of the signal produced by the
Noise Source. This source generates a random waveform producing pitch-less sound.
Two colors of noise are available − white, or high-pitched, and pink, or low-pitched.
These are selected by the Noise Quality switch (H), labelled WHITE/PINK. As an audio
signal, the Noise Source may be fed into the mixer by turning on switch (F). As a control
signal, it is available through the Modulation Mix, as described in the controllers section.

modifiers
The Modifiers section of the front panel features controls for the two sound modifiers, the
Filter and the Loudness Contour, which respectively shape the overtone content and
loudness/time contour of the audio signal as it passes through the modifying circuitry from
the mixer. In order to hear the effect of these controls, begin by setting the controls in the os-
cillator and mixer sections as follows:
Control Setting
Oscillator MODULATION SWITCH (A) off
Oscillator 1 RANGE (4) 16´
Oscillator 1 WAVEFORM (5) narrow rectangular (extreme right)
Oscillator 1 VOLUME (12) 7
Oscillator 1 MIXER switch (C) on
Other mixer switches (D, E, F, G) off
Switches (J) (K) (L) off
The controls on the Modifiers section should still be set as shown in Fig. 1 of the section
titled setting up the instrument.
filter and filter contour
The Mini Moog features a wide-range lowpass filter. This filter attenuates, or cuts out, those
frequency components of an audio signal which lie above a variable cutoff frequency, while
passing those components which lie below it.
1. The CUTOFF FREQUENCY control (17) is used to set the filter’s cutoff frequency.
Hold down a key and turn this control first clockwise, then counter-clockwise. You will
hear the tone become more shrill and then more muted, as the higher overtones are first
allowed to pass and then attenuated. If control (17) is moved all the way to the left, the
entire signal will be cut out.
2. The AMOUNT OF CONTOUR control (19) determines the amount of filter contour ap-
plied to the filter’s cutoff frequency. Each time a key is depressed, a contour generator
attached to the filter is actuated, and sends a control signal to the filter. The control signal
rises at one rate, then falls at a second rate, and finally levels off at a certain level. This
results in a corresponding rise, fall, and leveling off of the filter cutoff frequency, which
we call the filter contour.
Set the CUTOFF FREQUENCY to -2 and repeatedly depress and hold down a key while
setting the AMOUNT OF CONTOUR at various levels. The more this control is turned
up, the greater will be the increase and decrease in the brightness of each note. Controls
(17) and (19) have an additive effect on the cutoff frequency.
3. The ATTACK TIME control (20) determines the duration of the initial segment of the fil-
ter contour. The initial rise of the filter cutoff frequency can be as short as 10 mil-
liseconds or as long as 10 seconds. (The frequency at which the contour begins is deter-
mined by control (17), while the peak which it reaches is determined by controls (17) and
(19) combined.) Repeatedly depress a key while varying the setting of the ATTACK