Over the past decade, Arturia has done a terrific job of delivering virtual versions of some of the world’s most famous vintage analog synths, rightfully earning accolades and endorsements from top artists and journalists. More recently, they’ve expanded these products into iOS territory with their Minimoog emulation (iMini, reviewed June ‘13) and now, the Oberheim SEM, aptly named iSEM.
PROS: Spot-on implementation of SEM voice architecture. Sweepable filter curves. Full integration with iOS inter-app protocols. Decent monophonic performance even on an original iPad. Eight-voice mode allows subtle parameter offsets for each voice.
CONS: Virtual oscillators don’t have quite the aural density of the original SEM.
Bottom Line: Arturia’s emulation of the Oberheim SEM, now on your iPad.
In recreating the original SEM’s architecture, Arturia did their homework thoroughly, as always. The little quirks of the oscillator configuration, the continuously sweepable filter curves, the basic LFO and attack-decay-sustain envelopes (release is tied to decay, as on the Minimoog) are all in place, along with quite a few enhancements.
As with all Arturia vintage recreations, there are tons of intelligently designed amenities included with the original synth architecture. If you want to stay true to the essence of the instrument, you can skip these extras, but if you want to really ratchet up the sound, the tools are there. In the case of the iSEM, there’s a variable-wave sub-oscillator, a noise generator, an extra LFO with a wider array of waveforms, and some essential effects like overdrive, chorus, and delay, all integrated nicely with the iSEM user interface. There’s also a modulation matrix for assigning the LFOs, envelopes and all of the usual MIDI control sources to almost any parameter in the app.
The cherry on the sundae is that the iSEM is eight-voice polyphonic, and in a nod to the original Oberheim four- and eight-voice synths (behemoths comprised of multiple SEMs, a keyboard, and a programming panel in the same chassis), you can slightly offset the parameter values for each voice. Eligible parameters include cutoff, resonance, and tuning, and this facility really helps to recreate the subtle unevenness of discrete analog voices. This goes a long way toward capturing some of the feel of those original Oberheim polyphonic synths.
Beyond the synthesis tools, the iSEM is packed with the most modern iOS amenities, including Apple’s new Inter-App Audio connectivity, along with Audiobus, CoreMIDI, and Korg’s WIST protocol. This makes the iSEM a true team player in the iOS universe and easy to integrate with your iPad rig.
These bells and whistles, combined with Arturia’s deep experience with analog emulation, make the iSEM one of the better virtual analog synths available for the iPad. But the big question remains: Does it really sound like an SEM?
As an artist who owns and uses a modern Tom Oberheim SEM on a regular basis, I’d label Arturia’s iSEM as “evocative.” Arturia has done a solid job on recreating the SEM’s smoothly variable filter modes, which is no mean feat. It also behaves in a manner that’s faithful to the original, especially with the ability to tweak the character of individual voices in polyphonic mode. But the overall sound of a single voice just doesn’t have the heft and authority of the original analog hardware. It’s also worth noting that a real SEM costs around a grand and that’s just for one voice, so it’s a wee bit unrealistic to expect a $10 iPad app to replace that. It’s like the difference between looking at video of the Grand Canyon on a new 4K television. . . and standing at the edge yourself. You certainly get the impression of the scale and grandeur from the pictures, but not the actual experience.
That said, I still think the iSEM is a fantastic synth—among the best available for iOS, actually. Its combination of effects, enhanced modulation, and SEM-faithful signal path really puts it over the top in overall usability. So, if you’re looking for another analog flavor in your iPad rig, I heartily endorse this app.