Oberheim TVS-1

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"Technical Details:
The left-hand side of the unit contains the Sequencer. It is easy to use. The lower wide knobs control SEM #1, and the upper thin knobs control SEM #2. This allows for harmonies to the sequenced sounds, or doubling up of the sound for more powerful sequences. There is also a Sample & Hold (S/H) feature to the sequencer.

The External X/Y Controller Box controls the VCF’s (Voltage Controlled Filters), and the VCO’s (Voltage Controlled Oscillators). When the joystick is moved in the “X” left to right, it controls the VCO’s, changing the frequency. When moved up and down in the “Y”, it opens and closes the VCF’s. It makes for some very interesting sounds.

The two SEM’s (Synthesizer Expander Modules) allow for two-voice (two key) capability. Each SEM has two oscillators, which can be controlled separately, or synchronized by simply flipping the “Sync” switch. The SEM’s can also be used in unison, which makes for a very fat sound."