4True Analog Lives!
Marion Systems
True Analog Lives!
The Tom Oberheim TVS-PRO is a two-voice, two-way multi-timbral, pure analog synthesizer that incorporates
two classic Synthesizer Expander Modules with a 16-step, two-voice analog sequencer and a 37-note, two-voice
velocity and aftertouch keyboard. It is basically a re-creation of the original Two Voice synthesizer from 1975, but
with some interesting updates to the Mini-Sequencer, along with signicant enchancements to the audio sub-
system. And although a major design goal was to retain the essence of the original Two Voice, the TVS-PRO also
incorporates modern features such as MIDI In and Out, velocity and aftertouch keyboard facilities, and a univer-
sal, world-wide-capable power supply.
Of course, the heart of the TVS-PRO is the pair of Synthesizer Expander Modules. Each SEM is a true analog
synthesizer, very much like the original Minimoog, ARP 2600, and the Oberheim Four Voice and Eight Voice
polyphonic synths. What we mean by this is that the SEM is 100% analog! (Not just its “signal path.”)
Like many classic synths of that era, the SEMs are not programmable, which means that you can’t store patches.
But the idea behind the TVS-PRO, just as it was with the original Two Voice, is that it is meant to be PLAYED, but
not just the notes on the keyboard or the steps on the sequencer. The knobs are there to be turned!
Playback Assignments
The fun really begins when the two SEMs are integrated with the easy to use, 16-step Mini-Sequencer. This
integration of the two SEMs with the Mini-Sequencer is controlled by the ASSIGNMENTS section on the Mini-
Sequencer panel. This allows you to select one of three operation modes:
• Keyboard controlling both SEMs
• Keyboard controlling one SEM and the Mini-Sequencer controlling the other SEM
• Mini-Sequencer controlling both SEMs
• The random sample/hold control source controlling one SEM or both SEMs
Keyboard Modes
The 37-note two-voice polyphonic keyboard works in the following modes:
• Unison mode with and without Retrigger
• Two-voice polyphonic mode
• Split mode with the split point selectable
The keyboard has velocity and aftertouch capability which can be utilized to control various parameters in the
SEMs, such as lter frequency and overall module loudness.
Mini-Sequencer
The Mini-Sequencer is a classic 16-step analog sequencer using rotary knobs to set the pitches, quantized to
semi-tones. You can dene a sequence using the knob settings and the sequence is immediately functional.
Since the knob settings are stored in a temporary note memory, you can also dene a second sequence to
produce two-voice polyphonic operation with up to 16 steps per sequence.
Once you have created a two-voice sequence, the knob settings can then be stored in ash memory. Up to 50
two-voice polyphonic sequences can be stored.
