By Geary Yelton
THE FIRST SYNTH I OWNED WAS AN OBERHEIM TVS-1 FROM THE MID
’70s. It housed a pair of monophonic Synthesizer Expander Modules (SEMs),
giving it two complete and independent synthesizers as its voices. Because the
TVS-1 had no memory, I had to manually dial up new patches on both modules
to change sounds. A few years later I got an FVS-1—a large model with four
SEMs and partial patch memory. I eventually sold it to buy my dream synth, an
Oberheim Matrix-12. After I began using soft synths in the studio more often than hardware,
I became frustrated that you could get accurate emulations of practically every
classic synth except an Oberheim. Luckily, Arturia—best known for spot-on re-creations of
classics such as the Sequential Prophet-5, Roland Jupiter-8, and Yamaha CS-80—recently
launched SEM V, which emulates Oberheim’s SEM-based instruments and goes far beyond.
Tom Oberheim introduced the SEM in 1974 as a
monophonic expander for existing synths such as
the Minimoog and ARP 2600. Both the original
SEM and the new models that appeared in 2010
are freestanding boxes containing two voltagecontrolled
oscillators (VCOs), a multimode filter
(VCF), a sine wave LFO, and two envelope generators.
The oscillators can be synced and generate
sawtooth and variable-width pulse waves.
The two-pole filter comes in four flavors: lowpass,
highpass, bandpass, and notch. The envelopes
have attack, decay, and sustain knobs and modulate
the amplifier and filter frequency. With only
three knobs to control each ADSR envelope, the
initial decay and the final release times are identical,
and a single knob controls both parameters.
SEM V’s architecture and front-panel layout
are faithful to their hardware counterparts, but
with significant additions. A second LFO offers
sine, sawtooth, or square waves, and you can
sync it to your host software’s tempo, as well
as determine how quickly its effect fades in. A
versatile sub-oscillator generates the same three
waveforms, either one or two octaves below the
frequency of VCO 1. I was pleased to find you can
apply pulse-width modulation to the sub-oscillator’s
square wave. You also get a white noise generator
and some effects (overdrive, chorus, and
delay) as well as a basic arpeggiator that spans up
to four octaves. Clicking the Open button at the
top of the window reveals Modulations and Effects
sections above the front-panel interface.
One of my favorite tricks with my old TVS-1
was to play it monophonically with portamento
turned on for only one SEM. However, in SEM V,
portamento is applied to all voices.
On a vintage Oberheim four- or eight-voice
synth, you could either layer all the voices at
once (unison mode), trigger them one after the
other (continuous mode), retrigger the same
voices (reset mode), or assign specific SEMs to
either half of the keyboard (split mode). SEM V
duplicates continuous mode when played either
polyphonically or monophonically. Arturia says
there’s no unison at this time, but SEM V sounds
so fat in mono mode with the sub-oscillator on
that I could have sworn there was.
Because a separate SEM generates each voice
in a vintage Obie, every voice differs slightly
from the others, even when parameter values
are identical. This partially accounts for its huge
sound, and SEM V’s unique “8-Voice Programmer”
section mimics this by letting you off set
parameters for each of eight simultaneous
timbres. The Programmer displays six modulation
routings, each with a pop-up menu for
selecting from 24 parameters that include VCO
tuning, VCF mode, LFO rate, and the timing of
individual envelope segments. To their right is
a window that resembles a step sequencer, with
graphical blocks you can resize, representing
parameter values for each voice.
Although SEM V lacks a sequencer, you can
duplicate one by setting one of the Programmer’s
modulation routings to affect oscillator pitch,
selecting a pitch for each of the eight voices, and
turning the arpeggiator on so that it retriggers
SEM V’s Keyboard Follow function is more
sophisticated than your average keyboard
tracking. Like the Programmer, it can modulate
six simultaneous parameters of your choosing.
Each of the six assignments has its own response
curve controlling how the affected parameter
responds to note position. For each curve, you can
define as many as 32 breakpoints and specify
whether the slopes between breakpoints are linear
or exponential. The Keyboard Follow section
is where you can make your SEM V patches stand
apart from those of other synths.
Another page reveals SEM V’s Modulation
Matrix, which lets you define sources,
amounts, and destinations for up to eight mod
routings. You can choose from eight sources—
including either of the envelope generators—
and 26 destinations that include vibrato and
Batches of Patches
SEM V is loaded with hundreds of outstanding
patches, many created by top synthesists such as
Ian Boddy, Drew Neumann, and Erik Norlander.
Banks are further divided into types such as
Bass, Percussive, Sequence, and so on. Although
bread-and-butter-type sounds aren’t especially
plentiful, many of them are terrific.
|The 8-Voice Programmer mimics the subtle variations between SEMs in a vintage Oberheim by letting you offset parameters of your choosing.
Most of the factory presets are designed to
show off SEM V’s capabilities, and they can get you
on the road to creating your own patches. Your best
strategy for learning to roll your own may be to
check out the Modulations settings. You can pick up
a few tricks just by analyzing what Arturia’s sound
designers have done in that section.
I’m impressed by how well SEM V captures the
sound of Oberheim hardware, and its extended
features make it more flexible than its namesake.
I commend Arturia on reproducing the SEM’s
filter characteristics. SEM V is one of the most
genuinely analog-sounding soft synths yet. If you
love the sound of vintage synths, SEM V should
be part of your virtual rig.
PROS Sounds like a real
Oberheim SEM. Versatile
sub-oscillator and second
LFO. Unexpectedly deep
and subtle programming
CONS Portamento can only
apply to all voices at once.
POLYPHONY Up to 32 voices,
FORMATS Mac or Windows.
AU (Mac only), RTAS, VST,
COPY PROTECTION eLicenser
Control Center software—Internet
connection required for initial
If you’ve always wanted the legendary
and nearly unattainable Oberheim
Eight-Voice, this is the soft
synth for you.
$249 list | $199 street