AUDIO PLAYGROUND'S ARCHIVES OBERHEIM PAGES
The Oberheim Two, Four, Six, & Eight Voice
synthesizers were based on a
semi-modular design that was unique within the industry. The basic
building
block of the design was the Synthesizer Expander Module (SEM).
A complete
synthesizer in and of itself, it contains: Two Voltage Controlled
Oscillators (VCO'S), a four mode, two pole, Voltage Controlled
Filter (VCF),
Voltage Controlled Amplifier (VCA), Low Frequency Oscillator (LFO),
and
two Attack, Decay, Sustain (ADS) Envelope Generators.
The Oberheim Two Voice Polyphonic Synthesizer brings true polyphonic
operation and modular expansion capability to the compact synthesizer
field Fully loaded, this versatile Synthesizer contains two Synthesizer
Expander Modules, each of which is electronically a complete synthesizer,
an eight position, two voice Quantized Mini-Sequencer with Sample
& Hold, and a true two voice polyphonic, 37 note digital keyboard.
This powerful combination of precision electronic music modules
allows the synthesizer user to control two completely independent
synthesizer voices. For instance, the upper and lower voices from
the keyboard can separately be directed to the two Expander Modules
for playing two separate musical lines from the keyboard Or, the
Sequencer program can drive one Expander Module while the user
plays the second Expander Module From the keyboard. Or, the Sample
& Hold can drive one Expander Module while the Sequencer drives
the second n The secret to the Synthesizer's Flexibility is the
Synthesizer Expander Module. Despite its small size (7 1/2"
by 9" panel size) the Expander Module is a complete basic
synthesizer. All the essential circuitry necessary for a complete
synthesizer voice is included: two voltage controlled oscillators
(VCO's), a voltage controlled filter (VCF), two envelope generators,
a low frequency oscillator (LFO) and a voltage controlled amplifier
(VCA). In addition, numerous "patches" can be implemented
by using the pots and switches contained on the Expander Modules
front panel O The two voice digital keyboard can be operated in
either the polyphonic or monophonic mode When - operated polyphonically,
two separate and independent sets of control signals are available
to drive the Expander Modules. In the monophonic mode, both sets
of signals operate when a single key is pressed. This one key
depression can then drive four oscillators, Two filters and four
envelope generators, thereby making monophonic synthesizer sounds
previously available only to users of large studio synthesizes
. Two Voice Keyboard Electronics include a three position switch
which enables you to select left voice first. right voice first
or unison Also included is Portamento for the left and right voice,
a two octave Transpose switch and a Pitch Bend Pot with center
detent which covers a two octave range.
The Mini-Sequencer adds greatly to the Two Voice Synthesizer's
capability Basically, it consists of a dual output, : eight position
quantized analog sequencer, combined with a sample & hold
circuit and voltage controlled clock. The two separate control
voltage outputs from the Sequencer can be
used to generate two separate melodic lines through two Expander
Modules. or one control voltage output can produce the melodic
line while the second drives the voltage controlled clock to produce
the desired rhythm The Sample & Hold circuit is an integral
part of the Mini-Sequencer This circuit samples an internal noise
generator (the output of which is available as an audio input
to the Expander Modules) and includes controls for Range and Lag.
n An Output Module is included which contains a two input mixer
with master gain control for mixing together the outputs of the
two Expander Modules, and a headphone amplifier and 600 ohm line
driver circuit . For the synthesizer buyer on a budget, the Two
Voice Polyphonic Synthesizer can be purchased in its minimum configuration
of one Expander Module and the two voice keyboard. Then, at a
later date. the unit can be 1 expanded by the addition of a second
Expander Module and the Mini-Sequencer O Internally. the Synthesizer
is of rigid, 1. all-metal construction. The various modules are
mounted on sloping panels which, along with the keyboard, mount
on a robust. " aluminum plate. The entire assembly is then
packaged in a portable, vinyl covered case. Outside case dimensions
are 26" wide, 10" high. 19" deep. Weight is 45
lbs.
The 2 Voice has 37 Note keyboard, 2 Voice Polyphonic, 4 Oscillators,
Mini Sequencer w/sample & hold. made from 1976 to 1980 at
a list price of
$2195.00
The one on the Left is the fisrt set of Two Voice synths, The
one on the Right is the second Ver. of the Two Voice Synth.
The Oberheim Four Voice Polyphonic Synthesizer with
Polyphonic Synthesizer Programmer ushers in a new era in performance
studio synthesizers. It is the first commercially available synthesizer
on which four notes can be played simultaneously, plus have the
facility to store up to 16 different Programs (Patches) of your
own design Using versatile Synthesize Expander Modules as its
major elements. it is actually four complete synthesizers controlled
by a single keyboard. Each Expander Module is a complete synthesizer
voice, including voltage controlled oscillators, filter. amplifier
and envelope generators. The 49-note keyboard utilizes advanced
technology to generate independent control signals for each Expander
Module. A variety of keyboard controls are provided to enhance
polyphonic "playability' An output mixer allows a stereo
"pan" to be generated, producing an unusually live sound.
The result is a portable. live performance or studio synthesizer
far surpassing in capability other instruments in its price range,
and in many cases exceeding in capability large, expensive studio
synthesizers. O The special polyphonic keyboard is unique in the
synthesizer field. It uses special circuitry to search the keyboard
at high speed to detect when a note has been played. Upon detection
of a note depression, control signals are directed to an Expander
Module as determined by the keyboard logic and the settings of
the keyboard switches. Numerous playing options are provided by
these switches. The "Reset-Continuous" switch is used
to select whether successive notes are always assigned to Expander
Modules in ascending numerical order (1,2,3,4)
or whether a note is assigned to the Expander Module following
in sequence the last Expander Module assigned. The "Split"
switch effectively splits the keyboard in two equal parts and
the "1-3. 2-2. 3-1" switch assigns the lower and upper
halves of the keyboard to different independent combinations of
Expander Modules The "Unison" switch places the keyboard
in the monophonic mode, with each single key depression driving
all four Expander Modules. The "Portamento" switch causes
a portamento to occur on all four voices, with the rate controlled
by a pot. O The concept of a synthesizer "voice" is
basic to the mechanization of a polyphonic synthesizer. That is
to say, it is not enough to have four oscillators only to produce
four part polyphony, but rather four complete voltage controlled
synthesizer systems are needed, each one including not only oscillators,
but also a filter, two envelope generators and a voltage controlled
amplifier. In the Four Voice Polyphonic Synthesizer, this task
is accomplished by the Synthesizer Expander Module.
Despite its small size (7 1/2" x 9" panel size), the
Expander Module is a complete basic synthesizer. It includes two
voltage controlled oscillators (VCO'S), a voltage controlled filter
(VCF). two envelope generators, a low frequency oscillator (LFO)
and a voltage controlled amplifier (VCA). The precision and stability
of the Expander Module is unsurpassed. a quality that is absolutely
essential in a polyphonic situation where as many as eight of
sixteen (in the case of the Eight Voice) oscillators must stay
in tune with each other. · A four channel Output Module
is provided with the Synthesizer which consists of a four input
mixer with a Level control and Pan
control on each channel. a Master gain control, left and right
channel 600 ohm line outputs and a pair of stereo headphone amplifier
outputs. With the aid of the Pan pots, a stereo "spread"
of the four Expander Module outputs can be produced, which results
in a most effective "live" sound.
O Expansion capability has been provided for in the
Synthesizer. Although only four Expander Modules can be physically
accommodated in the Synthesizer case, the keyboard electronics
and the Programmer can be expanded to eight voices with the extra
voices' output signals brought out to a connector. When upgrading
to an Eight Voice an Eight Voice extension unit and interfacing
cables are provided. The additional circuitry required for the
expansion is added to the keyboard and Programmer electronics
via stackable printed circuit cards. A jack is provided for a
Master Filter Pedal.
Additionally, a cassette interface is available allowing complete
groups of sixteen programs to be dumped on a standard audio cassette.
using a standard cassette recorder and later be loaded back into
the Programmer. O Extra care has been taken in the construction
of the Four Voice Polyphonic Synthesizer to ensure trouble-free
performance. All circuitry is modular and easily removable. All
modules and the keyboard attach to panels which are rigidly held
in place by a 8" aluminum plate. The complete assembly then
mounts in a rugged vinyl covered wooden case. Outside case dimensions
are 42" wide, x 13.5" high x 19' deep. The unit weighs
79 pounds
The 4 Voice has 49 note, 4 Voice Polyphonic, 8 Oscillators, 16
Memory,
Cassette Interface, optional sequencer.made from 1976 to 1980
at
a list price of $5690.00
Not sure of this one , But it apears that a few black face Two
Voices were made.
The Oberheim Eight Voice Polyphonic Synthesizer
with Digital Programmer is undoubtedly the ultimate live performance
studio keyboard system available The flexibility of expression
available to the creative musician composer by having
eight complete synthesizer voices controlled by a single keyboard
is almost unimaginable The full. powerful richness
of having sixteen oscillators sound in unison is awesome and unique
to the Oberheim Eight Voice The Eight Voice is
basically two Four Voice Synthesizers with common keyboard. keyboard
electronics and Programmer Where you
have four complete synthesizer voices with the Four Voice you
now have eight, each includes two voltage controlled
oscillators (VCO's), a voltage controlled filter (VCF), two envelope
generators. a low Frequency oscillator (LFO) and a voltage
controlled amplifier (VCA). Additional keyboard and Programmer
logic is added to enable Eight Voice Polyphony and Programming
/ memory for the Extra Voices The keyboard assignment "Mode"
switches now affect all eight voices. i.e., the "Reset-Continuous"
switch selects Expander Modules in ascending numerical order (1.2,3,4.5,6.7,8).
The 1-3, 2-2, 3-1 switch now assigns the upper and lower halves
of The keyboard thusly, 2-6. 4-4. 6-2 The Unison switch
places all eight Expander Modules in the monophonic mode.
The Portamento switch causes portamento to occur on all eight
voices. The four additional Synthesize Expander
Modules and the extra stereo output module are housed In their
own case, similar to the Four Voice except keyboard, keyboard
electronics and Programmer are not included since they are provided
for with the Four Voice main frame. The outside dimensions of
the add-on unit are 42" wide x 13.5" high x 10.5"
deep. The unit weighs 45 pounds.
The 8 Voice has 49 note, 8 Voice Polyphonic, 16 Oscillators, 16
Memory,
Cassette Interface, optional sequencer.made from 1976 to 1980
at
a list price of $10,185.00
The Oberheim Polyphonic Synthesizer Programmer
(PSP-1) allows the musician to create
his "own" sounds, store them in a digital memory and
recall them with the touch of a finger
Sixteen totally different presets can be programmed and stored,
ready for recall on stage or
in the studio.
No longer does the multi-keyboardist need several synthesizers
on stage patched differently,
nor is he required to change patches under the pressure of live
performance. Also, he can be
assured of getting the same sound he got in the studio, because
it will be there in the digital
memory of the Programmer. As a matter of fact, many of his keyboards
are no longer
needed. The burdens of carrying freighting, packing, unpacking,
setting up, tuning, mixing,
patching and providing hard cases for four or more keyboards are
now over with the
Oberheim Four Voice Polyphonic Synthesizer and Polyphonic
Synthesizer Programmer combination.
The Programmer fits in a blank module location in the Four Voice
Synthesizer next to the
keyboard where it can be easily controlled by the player. The
most crucial parameter settings
are made at the Programmer control panel. Oscillator pitch, filter
frequency and modulation,
vibrato rate and depth, and envelope generator parameters (attack,
decay, sustain) can all be
set and stored separately for each Expander Module. All the normal
polyphonic keyboard
functions such as Pitch Bend. Portamento, Master Filter Tune,
and Keyboard Split are
unaffected by the presence of the Programmer.
Additionally a cassette interface is available allowing complete
groups of sixteen programs
to be dumped on a standard audio cassette, using a standard cassette
recorder and later be
loaded back into the Programmer The end result is you can build
a library of patches.
cataloged and stored on standard audio cassettes.
One more point worthy of mention is that your programs are not
lost when power is turned off.
Battery backup power is provided by standard batteries in the
Programmer and will last as long
as normal shelf life of the battery itself, typically 2 to 3 years.
The rest is up to you.