Oberheim OB-X8 Analog Synthesizer Demo + Review

Tom Oberheim is Back...with His Best Synth Yet

Ryan Gaston · 09/07/22

In the synth world, we're familiar with the names of a handful of early innovators: people whose inventions in the 1960s and 1970s had a profound influence on the course of music altogether. I'm think of people like Bob Moog, Don Buchla, Alan R. Pearlman, Dave Smith...and of course, Tom Oberheim. These people (and many like them) invented groundbreaking technologies, and ran companies dedicated to producing state-of-the-art electronic instruments designs.

In the years following their early crowning achievements, many of these inventors stepped away from the helm of their companies—for reason of financial hardship, or simply because they wanted to move on with their lives. Interestingly, though, we've seen many of them return, resurrecting their companies to continue to produce ground-breaking instruments in the 21st century, from Bob Moog's final instruments to Dave Smith's modern-day Sequential. But what about Tom Oberheim?

Well, Tom Oberheim has been making instruments all along—Marion Systems devices, special-run SEMs, limited edition updated Two Voice Pros, etc.—but recently, he regained the right to the Oberheim brand name and IP. First founded in 1969 and closing their doors in 1985, this company produced some of the most influential instruments of all time...and today, we're happy to announce that Oberheim is back in full force.

Reformed with the help of Sequential LLC., former employee and Line 6 founder Marcus Ryle, and Tom Oberheim himself, the 21st century Oberheim has announced the release of their first new instrument in 35 years: the OB-X8, a new design based on some of the most influential of all of their legendary instruments. Let's take a look at what's going on with the OB-X8, and how it fits into the ongoing Oberheim legacy.

OB-X8 and the OB Legacy

Oberheim's new OB-X8 is an eight-voice analog keyboard synthesizer that draws inspiration from some of the most iconic polysynths of all time: the OB-X, OB-Xa, and OB-8. These synths are responsible for some of the most iconic synth sounds of all time, from Van Halen's "Jump," Rush's "Tom Sawyer," Prince's "1999," and tons of other hits. But of course, if you're not familiar with these instruments, you might be wondering...what makes them so special?

Oberheim's classic SEM and the OB series are praised for having a particularly special liveliness, punch, and distinct tone. This is thanks in part to their embrace of discrete circuitry in the oscillator and/or filter designs...whereas later designs (such as the Xpander and Matrix-12) relied much more heavily on higher-level integrated circuits that packed basic synth functions onto individual chips, produced by Curtis Electromusic Specialties.

While designs that utilized these Curtis components can certainly sound incredible—in fact, the OB-Xa and OB-8 did employ Curtis filters—there's an undeniable magic in Oberheim's original, discrete designs that places his instruments in a class all their own. With a slightly different set of tolerances related to component selection, the instruments that featured discrete oscillator and/or filter designs had slight discrepancies in performance from voice to voice within the same instrument, making them feel organic and alive in a way that's difficult to approach with lower-tolerance, IC-centric designs.

Of course, I'm not knocking Curtis chips: the special sound of Curtis chips is another part of the sound and story of these instruments. The sound of Curtis filters, for instance, is a distinct characteristic of 1980s analog synth design, instantly transporting you back 40 years. If you're heard a vintage Sequential Circuits instrument, you should know what I mean. And that's some of the sonic magic that Oberheim has recreated with the new OB-X8: the combination of unique discrete circuits and embrace of some of the best-loved technologies from the 1980s. And of course, it's no accident that this is exactly what the new OB-X8 presents...a faithful reproduction of the specific oscillator circuits, filters, and other defining characteristics of each of these classic synthesizers.

So, that preamble behind us...what's up with the OB-X8?

The New Oberheim OB-X8 Analog Polysynth

OB-X8 is an Oberheim synth in the truest sense: an eight-voice, bitimbral, purely analog instrument with tons of discrete circuitry, punchy sound, rich filters, a friendly user interface...heck, it even has the classic pitch and modulation paddles. The OB-X8 panel features clearly-labeled, spacious controls on a classic gray-on-black background. Visually, the gray blocks denote the synth engine's primary function blocks: from left to right, a Master control section, Control section, Modulation section, Oscillator section, Filter section, Envelopes, Keyboard assignment controls, and Programmer. Let's look at each in detail, starting with the audio path itself.

Each voice features three sound sources: a noise source and two discrete analog oscillators straight from the SEM/OB-X lineage. The oscillators are the source of the classic Oberheim sound: a huge, raw tone with plenty of weight and punch. Each of the two oscillators allows access to sine, saw, triangle, and pulse wave shapes. The pulse waves have variable pulse width, oscillator 2 can be hard synced to oscillator 1, and there's even continuously variable cross modulation between the two oscillators—great for adding a lively sense of instability into your sounds. What's more, each of the oscillators has its own dedicated quantized tuning control, and oscillator two has a dedicated detune knob...so it's quite easy to dial in everything from huge-sounding stacked intervals to massive detuned tones. There's also a unison mode for invoking all eight voices simultaneously, for particular Of course, you could elect to use only one oscillator per voice for cleaner/thinner sounds...but I'm sure the temptation will always lead me to let both oscillators blast. Can't help it, it's just who I am.

The filter is where things get particularly fun. The filter section is one of the places where the OB-series synthesizers differed from one another...and in the OB-X8, we get the best of all worlds. The filter offers a switchable "type" parameter allows access to each version of the classic Oberheim filter sound. At the flick of a switch, you can change between discrete SEM-lineage VCFs, capturing the raw spirit of the original OB-X, and Curtis chip VCFs...matching the character of the OB-Xa and OB-8. You can easily access a keyboard tracking option for the filter, and what's more, the OB-X8 is hiding a number of additional SEM filter modes behind the surface, providing highpass, bandpass, and notch functionality to the OB-X filter. If your jaw didn't just drop, I'll punctuate this fact by simply saying that the inclusion of these additional SEM filter types is just...really, really cool.

The modulation section itself also allows for a host of incredible sonic animations. The built-in LFO offers sine, square, saw, ramp, and sample & hold shapes, and features two mod busses with independent depth controls: one which allows modulation of the oscillators' pitches and filter's cutoff frequency, the other of which provides per-oscillator PWM and final amplitude modulation. The envelopes are directly tied to the filter and amplifier, though the filter envelope can be made to perform oscillator pitch modulation—great for patches that employ sync or audio-rate filter modulation. The envelopes are modeled to specifically match the behavior of each vintage OB synth...providing a sound and feel entirely accurate to the originals.

There are, of course, a number of additional expressive features—perhaps most notably that the Fatar keybed is both velocity and pressure-sensitive, allowing for expressive patches employing (monophonic) aftertouch. Velocity can be easily assigned to the filter's cutoff and the VCA loudness; aftertouch can be applied to the filter or even to modulation depth. The "control" section additionally allows for portamento, and even features the "vintage" function first introduced in Sequential's recent re-release of the Prophet-5. If you've not played a new Prophet-5, I'll take a moment to stress that this "Vintage" function is surprisingly well-implemented. It's not just like a traditional "oscillator slop" control—it taps into many parts of the circuit, imparting subtle instabilities between voices that range from barely-perceptible to outright seasick. It's an amazing and finely-tuned function, and I'm truly excited to experience what it can do applied to an Oberheim synth architecture.

Now, one other significant thing worth mentioning: the OB-X8 is bi-timbral. It allows for simultaneous access of any two presets, which can either be split or layered across the keyboard, making for an insane level of depth and sonic possibility (about which I'm currently getting goosebumps). And while on the topic of presets, the OB-X8 includes 400 factory programs, including all of the factory sounds originally found in the OB-X, OB-SX, OB-Xa, and OB-8. Yep, it really is all of these synths rolled into one. (There are over 600 user-programmable preset locations in total.)

Of course, there's more: the left-hand controller section features the two classic Oberheim modulation paddles for expressive access to pitch bending and vibrato controls (with an independent LFO for performance modulation, enacted via the levers). This section also features the arpeggiator controls, allowing you to create sonic flurries at whim. This will prove particularly useful in creating deeply interesting layered patches.

Additional niceties include variable oscillator and noise levels (as opposed to purely switch-based mixing control), per-voice stereo panning (!!!), and other quality-of-life features including MIDI In/Out/Thru, USB MIDI communication, volume/sustain/filter input jacks, and a dedicated arpeggiator clock input. Lest we forget—it also uses an integrated fanless, heatsink-free power supply...which, in the 1980s, wasn't necessarily a given.

Oberheim + the Future

Overall? I couldn't be more excited about the OB-X8. Frankly, it's super exciting that Tom Oberheim is back at the helm of his company, and that the world gets to see yet another inspiring Oberheim design. I'm also thrilled that the OB-X8 isn't just a modern-day re-tooling of a vintage instrument. Much like the re-released Prophet-5, this design is full of new features that help to bring the sound of classic instruments up to the standards of 21st-century instrument design—retaining the sound of its predecessors, while making for an altogether much more expressive and inter-connectable instrument.

In some ways, that makes the OB-X8 a clearer realization of the humanness of these designs altogether, and I'm beyond excited that the world now gets to see what an honest-to-goodness, fully-featured, no-compromises, 21st-century Oberheim instrument would be. No doubt we'll see an enormous range of new music, and—with luck—perhaps even more new instruments as well.