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Oberheim OB-X

Category	Electronic (analog polyphonic synthesizer)
Country of origin	USA
Classification	analog synthesizer
Wikipedia	en.wikipedia.org
Wikidata	Q3347942

Overview

The Oberheim OB-X is an analog polyphonic synthesizer released in 1979. It was Oberheim’s first integrated polyphonic instrument with a built-in keyboard, programmable patches, and four, six, or eight voices depending on configuration. The OB-X established the warm, layered Oberheim sound that would be refined in the OB-Xa and OB-8 successors.

Origin & History

Earlier Oberheim polyphonic synthesizers, such as the Four Voice and Eight Voice, were assemblies of separate Synthesizer Expander Modules controlled by an external module. The OB-X integrated voices, controls, programmable memory, and keyboard into a single instrument, following the lead of the Sequential Circuits Prophet-5 which had appeared the previous year. It was produced for only about two years before being replaced by the OB-Xa, which used different filter chips and offered greater stability and lower cost.

How It’s Played

The OB-X is played from its built-in keyboard. Each voice has two oscillators with several waveforms, a noise source, a low-pass filter, two envelope generators, and an LFO. Patches can be saved to memory, removing the need to reset front-panel controls between sounds. Performance features include split and double modes that allow two patches to be combined across the keyboard.

Cultural Significance

The OB-X became part of the foundational sound of late-1970s and early-1980s rock and pop. Its discrete-component design and warm filter response give it a sound that is often described as having particular depth and density, especially on pad and brass-style patches. Original units are highly collectible, and modern Oberheim-branded reissues have aimed to recreate its character.