Moog Minimoog, Minimoog Model D Operation 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

mixer
modifiers

modulation mix
others

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 intercon­nected 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 ar­ranged 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 in­strument creatively and efficiently.

basic mini moog features

The Mini Moog contains the basic components and features to be found on larger, studio­oriented 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 con­tour 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 intro­duced 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 tim­ing 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, guitar­type 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 VOL­UME 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 head­phone 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. Re­turn 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 Os­cillator 1. To hear this, turn on switches (C) and (E), turn off (G), and depress a key. Ad­just 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 discon­nected 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.