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Oberheim Xpander

Desktop Synthesizer Module

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Xpander 1Xpander 2Xpander 3Xpander 4
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Oberheim Xpander
Oberheim Xpander
2 500.00 street price

In 1984 Oberheim tried to assemble a modular system in a relatively small housing with the ability to quickly and easily integrate with other devices. The result was Xpander which combines the flexibility of a modular system with the ease of controlling a digital synthesizer. The sound is produced by an analog circuit and, while the signal passes through all function blocks, it remains analog (it is not digitized, it does not pass through the ADC/DAC).

Six CEM3374 chips (one for each voice) are responsible for creating the primary sound wave they are represented by two independent VCOs combined in one housing. Each voltage controlled oscillator can produce a triangular, sawtooth or pulse wave. The sync mode, "detune" and frequency (FM) modulation of the two VCOs are available.

At the output of each voltage controlled oscillator there’s an independent VCA. Then the signal of two VCOs is mixed in VCF, after which the signal passes through two independent VCAs put in series.

The voltage controlled filter (VCF) can operate in four modes: low-pass, band-pass, notch and high-pass. In this case, the slope can be set to 6 (one filter stage/pole), 12 (two), 18 (three), 24 (four) dB per octave.
In addition, Xpander includes a number of separate digital function blocks that can be used to modulate any element of the system:

Envelope generators - each voice can have up to five ADSR envelope generators, and you can additionally set a value for the delay (the initial envelope stage). So the generators are presented by DADSR.

LFO - five independent low frequency oscillators producing a triangle, meander, saw, reverse saw and noise.
The Lag generator is a function generator similar to the traditional portamento. However, it can be routed not only to pitch, but also to control any audio signal.

Ramp generator - produces a control signal that increases linearly from zero to the specified value.

Settings can be saved in one of a hundred patches, and up to hundred multitimbral presets can be made out of patches.

Xpander has advanced MIDI support: each voice or group of voices can be assigned to a separate MIDI channel. There are also connectors for CV signal input/output, which provides integration of Xpander with modular systems.

Oberheim Xpander was used in the works of Cirrus, Josh Wink, Astral Projection, Vince Clarke, Mark Isham, Die Krupps, DJ Sasha, Chemical Brothers, Frontline Assembly, Front 242, Mitchell Froom, Gas Chamber Orchestra, Meat Beat Manifesto, Nine Inch Nails.

Tags: analog synthesizer

Country of origin / production: USA

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More info
Usage area
Sound Module/ Tone Generator 
Usage Design/ Form Factor
With Separate Keys Module 
Without Keys, Desktop 
Hybrid, Digital+Analog 
Tone Generator / Sound Synthesis
Synthesis Method Frequency Modulation (FM)
Oscillator Type VCO (Voltage Controlled Oscillator)
Oscillators per voice2
Waveform/ Spectral form (main generator) Pulse Width Modulation (PWM)
Waveform/ Spectral form (main generator) Triangle
Waveform/ Spectral form (main generator) Saw
Programs/ Voices/ Timbres
User-defined Multitimbral100
High-pass Filter (HPF) 
Low-pass Filter (LPF) 
Band-pass Filter (BPF) 
Band-reject Filter (BRF/ BEF) 
Envelope Generator (EG)
Arpegiator/ Portamento
General MIDI (GM) 
MIDI in/ out
Display type TFT
Color resolution Monochrome
Audio out
Dedicated output per voice 
Analogue: 1/4" (6.35mm)9
Voltage 230V
Voltage 120V
Voltage 50-60Hz
Power Supply Built-in, internal
Height125 mm
Width825 mm
Depth312 mm
Weight14.7 kg
Case/ body
Production start1984
Production end1988
Production ended

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Oberheim Matrix 12
/5 0

  Polyphonic Analog Synthesizer   4 500.00 U.S.Dollars

Matrix 12 is a programmable analog polyphonic synthesizer with the functionality of the modular system. It represents two Xpander modules combined into one housing with a five-octave dynamic keyboard. The control panel is identical to Xpander one, with a...