The Voltage Modular Synthesizer Expander Module is an emulation of the classic Oberheim® Synthesizer Expander Module, aka the "SEM." Originally released in 1974, the keyboardless, mono SEM module was intended as a companion to the Oberheim DS-2, one of the earliest digital sequencers. Though it was a simple, barebones monosynth, the SEM sounded fantastic, and had a tone quality very different than the common fuzzy, fat Moog sound, thanks to its 12 dB/oct state-variable filter. With lowpass, bandpass, highpass and notch modes, this flexible filter was the star of the show. We've precisely recreated it here with a detailed emulation programmed by award-winning synth designer, Mark Barton (MRB). The design is similar to the "patch panel" reissue SEM's released in the 2000's; these were basically identical to the 70s versions but added an extensive patch panel for modular synth flexibility.

Disclaimer: Oberheim® and SEM are trademarks of Tom Oberheim. There is no association, affiliation or endorsement of Cherry Audio or its products by Tom Oberheim.

Doc Joe

Jul 30, 21

Pure joy

The EightVoice is one of my two "go to" softsynths these days. It is the near perfect sound of joy from my childhood: thick, lush, wide and spacious. The Expander modules (poly and mono) are likewise beautifully crafted, bringing even more possibilities through Voltage. The level of sonic control you obtain by driving every aspect of the Expander module via CV is... awesome. Imagine four of these units, each with subtle variations, all singing together, but with S&H and glacial glides on different parameters ... its as close to complex sonic perfection as you can get.