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Oberheim | SEM with MIDI to CV Converter


The Tom Oberheim Synthesizer Expander Module with MIDI to CV Converter shares the exact sound-producing components as the SEM above. Rather than using a patch panel approach, this version includes a precision MIDI-to-CV converter that has been specifically designed to allow MIDI to control the SEM, and has additional features that make use of the SEM's external inputs.

MIDI-to-CV Converter features:

• Select MIDI channel, controller number and bend range
• Select note assignment modes: latest, high note and low note priorities
• Select note re-trigger, filter track, LFO reset.
• A second independent control bus allows velocity, controller data or channel pressure to modulate either or both VCOs, the filter and the VCA.
• Transpose function allows different keyboard controllers to utilize the complete MIDI note range.
• Analog portamento.
• Input preamp gain control - allows an external audio input to be processed thru the SEM.
• Precision A-440 Hz tuning signal.
• Control voltages and gate are bought out to rear panel connectors so MIDI-to-CV function can be used with other CV/Gate gear.
ModelSEM with MIDI to CV Converter
Engine TypeAnalog
Voices (max)1
LFO1 Triangle
Engine Detailed2 VCO's (per voice) with sawtooth or variable-pulse waveforms
Filter (VCF)2-pole multimode (low-, band-, hi-pass, band-reject) VCF with ASR (Attack, Decay and Sustain) generator
Envelope (VCA)2 ADR (Attack, Decay and Sustain) Envelope Generators
SequencerMini Sequencer (with 8 steps and 2 voices)
Key typeN/A
CV-gateCV I-O
Produced:2010 - 2010
Legend: Obvious Y: Yes, N: No, N/A: Not Applicable
VCO Voltage Controlled Oscillator DCO Digital Controlled Oscillator
LFO Low Frequency Oscillator Sub Sub Oscillator
VCF Voltage Controlled Filter VCA Voltage Controlled Amplifier
Velocity As with a piano, the harder you hit a key, the louder the sound, unlike most organs which always produce the same loudness no matter how hard you hit a key. Aftertouch Pressing a key after you activated it. Channel Aftertouch, no matter which key, it will send a Channel message. Poly Aftertouch, sends the pressure per key instead of the whole channel.
Values for OSC, LFO, Filter, Envelope are per voice unless stated otherwise.

Manuals, patches etc.


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