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The Moog Modular System 55
Please Note: Payment for the Moog System 55 can only be accepted via Cashiers Check, Money Order, or Bank Wire Transfer. No credit cards, please.
As you know, the Moog System 55 is a highly sophisticated and dynamic analog instrument comprised of 36 handcrafted modules and housed in 2 hand-finished solid walnut cabinets. This magnificent creation provides limitless sonic potential and inspiration, while delivering the depth and dimension of sound found only in a vintage Moog modular synthesizer. The System 55 comes equipped with the coveted 960 Sequential Controller for incorporating extensive rhythmic complexity and expanse into the creative process.
Faithfully Recreating the System 55
Over the course of 3 years, Moog Music set out to research and build a faithful recreation of the classic Moog modular System 55. Using all original documentation as well as circuit board and art files for every module, Moog Engineers have painstakingly recreated this incredible analog instrument.
Each System 55 is hand-built to its original 1974 Moog factory specifications and is a true recreation of the original. Individual modules are brought to life just as the originals were, by hand-stuffing and hand-soldering components to circuit boards, and using traditional wiring methods. Each module is then finished with a photo-etched aluminum panel, and placed in its new modular instrument.
This limited reissue of the Moog modular System 55 is built to order, and is available in highly limited quantities. Only 55 units will be made.
System 55 Modules
5x 902 Voltage Controlled Amplifiers
1x 903A Random Signal Generator
1x 904A Voltage Controlled Low Pass Filter
1x 904B Voltage Controlled High Pass Filter
5x 911 Envelope Generators
1x 911A Dual Trigger Delay
1x 914 Fixed Filter Bank
1x 921 Voltage Controlled Oscillator
2x 921A Oscillator Drivers
6x 921B Oscillators
1x 960 Sequential Controller
1x 961 Interface
1x 962 Sequential Switch
1x 992 Control Voltage Panel
1x 993 Trigger and Envelope Voltages Panel
1x 994 Dual Multiples Panel
1x 995 Attenuator
1x CP2 Console Panel
3x CP3A Console Panels
1x CP8 Console Panel
1x 350 Watt 120 VAC or 230 VAC Switch Selectable Power Supply
Included Patch Cabling
14x - 1' 1/4" TS cables
12x - 2' 1/4" TS cables
12x - 3' 1/4" TS cables
6x - 4' 1/4" TS cables
4x - 5' 1/4" TS cables
2x - 1' S-Trigger cables
3x - 3' S-Trigger cable
1x - Y-cable S-Trigger
Weights and Dimensions (approximate)
Main Cabinet: Weight: 100 lbs., Dimension: 48 1⁄2" wide x 15 1⁄2" high x 14" deep
Upper Cabinet: Weight: 60 lbs., Dimension: 48 1⁄2" wide x 10" high x 8 1⁄2" deep
Shipping Weights and Dimensions: 2 Crates total:
Main Console: 140 lbs, 59.8" L x 18.8" W x 28.8" H
Expansion Cabinet: 100 lbs, 53.3" L x 13.3" W x 17.3" H
Modules And Their Original "Functional Descriptions"
902 Voltage Controlled Amplifier: The 902 voltage Controlled Amplifier is a differential input and output circuit which gives an overall voltage gain of 2 {6dB} when the manual control potentiometer is at maximum {6}, or when a control voltage of 6 volts is applied to the control input. Maximum sum of control voltage {fixed control voltage and input jacks} is approximately 7.5 control volts, producing +4.7dB or gain of 3. Two modes of gain response are available: linear and exponential.
903A Random Signal Generator: The Random Signal Generator produces continuous bursts of random frequencies and waveshape from approximately 25Hz to 20kHz. Two types of energy distribution are
provided: white noise and pink noise. The former distributes amplitude evenly throughout the indicated audio spectrum- The latter reduces the amplitude of each frequency increment proportionally to produce equal energy per octave. Pink noise, thus, sounds "lower" in pitch to the
ear.
904A Voltage Controlled Low Pass Filter: The 904A Low Pass Filter attenuates frequencies above the fixed control voltage cutoff point at a rate of 24dB per octave. The cutoff point {cutoff frequency} is voltage controlled through the control input jacks. The sum of the applied control voltages doubles the frequency of the cutoff point for each one-volt increase {volt per octave standardization}. The regeneration potentiometer {variable Q} varies the amount of internal
feedback, creating a rEsonant peak at the cutoff frequency. This resonant peak will break into oscillation at clockwise settings of the
regeneration pot, creating a voltage controlled sine wave generator.
The fixed control voltage pot covers a 12-volt {octave} range. The
overall range of the FCV pot is determined by the Frequency Range
switch, which moves the frequency cutoff range in two-octave steps.
The basic cutoff frequency of the Low Pass Filter is determined by the
combination of fixed control voltage and frequency range in addition to
the control input signals. An increase in regeneration narrows and
increases the strength of the cutoff frequency peak, while decreasing
the amplitude of the lower frequencies.
904B Voltage Controlled High Pass Filter: The 904B Voltage
Controlled High Pass Filter attenuates input signal frequencies below
its nominal cutoff frequency setting. The attenuation below FCV cutoff
setting is 24dB/oct. As the fundamental is generally the loudest
frequency component of a complex tone, deletion of the lowest frequency
range can radically alter the timbre. The FCV cutoff point is raised or
lowered in octave per volt control inputs.
The Frequency Range switch sets the overall range of frequencies
covered by the Fixed Control Voltage potentiometer. The Low range
encompasses 4hz to 20kHz, while the High range shifts 1 1/2 octaves up
to 10Hz through 50kHz.
911 Envelope Generators: At the introduction of a
switch-to-ground {S-trigger} trigger signal from an external source,
the 911 Envelope Generator produces a single voltage contour whose
time/voltage variation is determined by potentiometers T1, T2, T3 and a
time constant sustaining level pot {Esus}. Closure of the input trigger
switch directs the voltage contour to T3 {final decay} regardless of
what stage { T1, T2 or E} was in current operation. The Envelope
Generator requires an S-trigger to operate. External sources must be
converted to the S-trigger format via the 961 Interface.
911A Dual Trigger Delay: The 911A Dual Trigger Delay is
designed to be used with 2 or more 911 Envelope Generators. It provides
one or two time delays on an input trigger voltage - bound for the
activation of an envelope switch trigger. Three different modes of
operation are available via coupling mode switch:
OFF: Delays are activated independently through individual trigger
inputs.
PARALLEL: Trigger input to top 911A activates timing circuit on both
simultaneously.
SERIES: Trigger input to top 911A activates top timing circuit then
triggers second upon activation of first.
914 Fixed Filter Bank: Similar in function to the Moog 907A Fixed
Filter Bank, the 914 Extended Range Fixed Filter Bank is a non-voltage
controlled modifier with 14 separate passband controls: high pass, low
pass and 12 center frequency knobs. Each passband range has an
attenuation slope of 12dB per octave above or below the center
frequency indicated.
921 Voltage Controlled Oscillator: The 921 Voltage Controlled
Oscillator is a variable waveform generator, which produces frequencies
ranging from .01Hz to 40kHz. Four waveforms are available: Sine,
Triangular, Sawtooth, and Rectangular {with variable duty cycle}. Both
fixed and variable levels can be obtained from front panel output
jacks. Nominal frequency is set manually by the scale, coarse range,
frequency and {octave} range controls found at the top of the module.
Voltage controlled rectangular width is set by the knob in the upper
center {left}, with accompanying voltage input jacks. Clamping point
{waveform reset control} may be set with the lower left knob and
accompanying trigger inputs to the left. Multiple frequency control
inputs can be plugged into this module in parallel. All waveform
outputs can be used concurrently if desired.
All manual controls on this module can be moved or switched during
operation. This module functions as both an audio or control voltage
generator.
921A Oscillator Drivers: The 921A Oscillator Driver is a control
voltage processor, which drives associated 921B oscillators through
internally wired connections {via edge connectors}. Two voltages are
generated: one for frequency control and one for rectangular wave duty
cycle. Control inputs to this module change the frequency of its
associated oscillators in volt/octave increments. Manual adjustment to
the Frequency and Width Of Rectangular Wave pots changes the nominal
frequency and duty cycle of all connected 921B's in parallel. Two
ranges are provided on the Frequency potentiometer: semitone {two
octaves compass} and octave {12 octaves compass} These ranges are
selected by the white switch below the Frequency potentiometer. Control
inputs for frequency and rectangular width are summing.
921B Oscillators: The 921B Oscillator generates frequencies from
1Hz to 40kHz minimum. They are wired in groups to a common 921A
Oscillator Driver, which provides both exponential frequency control
and rectangular width voltage control. Like the 921 Oscillator, this is
one of the building blocks of analog synthesis. This oscillator
generates both sub-audio and audio frequencies for control and audio
signal use. The Frequency pot at the top of the module has a two-octave
range for fine-tuning, while the Range switch shifts the frequency of
the oscillator in octaves, up or down. Number indications on the Range
switch correspond to traditional organ pipe range notations. Fixed
level outputs for Sine, Triangle, Sawtooth and Rectangular waveforms
are found at the right of the modules. DC Modulate is a linear
frequency control input {does not conform to 1 volt/octave control
voltage format}. AC Modulate input is a capacitor-coupled circuit like
the DC Modulate input, however, blocking constant DC voltages.
921B Oscillators may be phase locked together via the Synch input jack
and the associated three position Synch Switch. Phase locking
capability is generally limited to the first six harmonics of the input
signal. A sawtooth waveform is recommended for best synchronization
results.
960 Sequential Controller: The 960 Sequential Controller has a
wide variation of functions, both as an independent module and in
combination with the 961 Interface and 962 Sequential Switch.
The sequencer module consists of a voltage controlled clock oscillator,
which drives three rows of eight steps each. Indicator lights show
sequence and step position status. A separate potentiometer for each
step permits up to eight different voltage settings to be selected for
each row. The DC voltage output corresponds to the column of pots below
the lighted stage. Voltage range switches for each row determine the DC
voltage range of each pot with two volts {X1}, four volts {X2}, or
eight volts {X4} maximum extent. Two parallel outputs are provided for
each row. Jacks for trigger inputs and outputs appear below each
column. Trigger inputs activate that stage independently of the clock
oscillator trigger. Trigger outputs are available for any other
V-trigger activated input. Manual trigger buttons as well, are included
for each of the eight stages {found below the V-trigger jacks}.
Switches found immediately below each step position permit normal, skip
or stop functions. A ninth position providing skip {continuous
progression through the eight steps} or stop {one progression to
closure} functions is included at the end of the row. Timing control
for the eight steps is accomplished via the Third Row Control of Timing
switch. This switch connects the third row of the sequencer into the
control input of the clock speed for each stage according to the
settings on the third row potentiometers. The Shift input admits an
external clock input to the sequencing circuit. This input may be used
in addition to or exclusive of the internal clock oscillator trigger.
Manual shift from step to step is accomplished with the button next to
the shift input jack, as well as individual manual trigger buttons for
each step found under each step column.
Manual buttons or external v-trigger sources initiate the clock
oscillator start and stop functions. The clock oscillator is capable of
producing frequencies from .1Hz to 1kHz. It has both octave {range} and
vernier {fine adjust} controls. One control input jack is available, as
well as one rectangular wave output {approximately 90/10% duty cycle}.
The clock oscillator, like other Moog oscillators, is standardized to
one volt per octave.
961 Interface: Four independent circuits are found on the 961
Interface: one Audio-In to V-trigger Out circuit, one S-trigger In to
V-Trigger Out circuit, and two V-trigger In to S-trigger Out circuits.
All interface circuits may be used simultaneously, in combination, or
separately.
The Audio to V-trigger circuit generates V-triggers when the audio
input level rises above the threshold set on the Sensitivity
potentiometer. This V-trigger sensitivity varies with the frequency
band of the audio signal and with the frequency of its amplitude peaks.
V-trigger duration is commensurate with the length of time the audio
signal remains above the sensitivity threshold. Two parallel V-trigger
outputs are included.
The S-trigger to V-trigger circuits converts any Short-to-ground
trigger input to a v-trigger output.
Each V-trigger In to S-trigger Out circuit has two columns of six jacks
each for input triggers and one S-trigger output. Column A of the
V-trigger inputs will convert V-trigger signals to S-triggers with
duration equal to the input. Column B determines S-trigger duration by
the Switch-on-time knob ONLY. B Column S-triggers will block, extend or
fore-shorten Column B V-trigger inputs to conform to whatever duration
is indicated on the B-column potentiometer. A minimum switch-on-time of
40 milliseconds and maximum time of 4 seconds duration is available.
Simultaneous inputs to both A and B columns may be made. Simultaneous
inputs to two parallel jacks will result in the longer of the two
trigger signals being accepted.
962 Sequential Switch: The 962 Sequential Switch selects between
two or three signal inputs, coupling one signal to the output jack at a
time. A V-trigger pulse introduced to the Shift Input initiates the
sequence. The Sequential Switch will alternate between stages One and
Two, disregarding stage three until a standard {tip-sleeve} phone plug
is patched into Signal Input Three. A connection to Input Three will
cause the Sequential Switch to alternate between the three stages {in
order) when triggered. Separate V-trigger input and output jacks are
provided far each of the three stages, as well as buttons for manual
switching. A small light for each stage indicates its status, on
{coupled to the output} or off.
992 Control Voltage Panel: The 992 Control Voltage Panel is used
for routing up to four control voltage signals to the 904B Low Pass
Filter. The fourth input on the panel contains a signal inverting
attenuator circuit.
993 Trigger and Envelope Voltages Panel: The Trigger and Envelope
Voltages Panel is a signal routing module for S-triggers coming from
one or two controllers. Lighted switches labeled "FROM 1" and "FROM 2"
at the top of the panel connect the controller trigger outputs (when
lighted) to the 911A Dual Trigger Delay. The lower three left hand
column switches route the trigger signal as follows: top switch - to
left 911 with no delay, center switch - to center 911 with delay set by
top 911A delay unit, bottom switch - to the right 911 with delay set by
the bottom 911A. The right hand green switches connect the DC control
voltages from the 911's to their respective 902 Voltage Controlled
Amplifiers: Left to left, center to center, right to right.
994 Dual Multiples Panel: The multiple is a device, which
permits multiple distribution of one signal to several different
places. This process is often called signal splitting. Multiples are
used for many purposes; from linking two patch cords together, sending
a single signal to several different modules at the same time, to
doubling or trebling the amplitude of a signal by sending it X3 to a
particular source.
995 Attenuator: Attenuators reduce the gain or amplitude of any
applied input signal, control or audio. Moving clockwise from zero gain
to unity with input, these attenuators can be used for reducing the
effect of a control upon a voltage controlled module, providing up to
three variable outputs from a single source input or reducing the gain
of an entire signal complex.
CP2 Console Panel: specifications to be provided
CP3A Console Panels: The CP3A module has four varied functions.
The primary circuit is a 4x1 mixer with positive and negative outputs
and a maximum gain of 2x. This mixer can combine both AC and/or DC
voltages. The second series of functions are four signal routing
switches, which connect the incoming control voltages from keyboard,
ribbon or other controller units to the frequency control input of
associated oscillator drivers found directly above the switching panel.
The fourth input switch has both an external input jack and attenuator
{found directly below}. This input jack is connected to the Oscillator
Driver when the associated switch is on and the attenuator set above
zero. At "10" a signal introduced here will be equal to one which is
introduced directly into the frequency control inputs found on the
Oscillator Driver itself. The two final elements found on the CP3A are
a multiple {signal splitting - one input becomes three} and trunk line
jacks, which carry a signal to the rear of the synthesizer.
CP8 Console Panel: specifications to be provided
