PROS
Massive sound. Audio-range LFOs.
Snappiest envelopes we’ve ever heard.
USB-to-CV conversion for controlling
vintage synths via MIDI or from your
DAW. Fully analog knob pots mean no
encoding artifacts.
CONS
No preset memory. Configuring and
using arpeggiator and advanced MIDI
functions is extremely fiddly. LFO waveforms
are limited to triangle and square.
Mono audio output only.
INFO
$625, doepfer.de
U.S. dist. by Analogue Haven,
analoguehaven.com

HANDS-ON
- The oscillator blends a square wave with triangle
and sawtooth options. To isolate either, turn the
PW knob to a 0:100 ratio.
- The 24dB-per-octave filter has a very Moog-like
sound at low resonances.
- Classic modular CV ins and outs, including VCO
pitch, filter cutoff, pulse width, and LFO, are in
this row of 1/8" mini jacks.
- This 1/8" input lets you pump external audio
through the filter and VCA. The mono audio output
uses a 1/8" jack as well.
- Dual LFOs work in low, medium, and high ranges,
with maximum frequencies in kHz — well into the
audio FM range.
- ADSR envelope includes multiple speeds for
super-snappy transients.
NEED TO KNOW
Is it fully analog?
Every component,
from audio signal path to modulation,
is completely analog, giving the Dark
Energy a monster sound that virtual
synths still can’t equal.
What makes it modular?
CV ins
and outs let you interface it with other
analog, voltage-controlled gear.
Can I play it from a MIDI keyboard?
Yes. You can also sequence it from
your computer via USB, and it can
even act as a MIDI-to-CV interface for
your other analog gear!
How does it compare to the Dave
Smith Mopho? Moog Little
Phatty?
Unlike those, Dark Energy
can’t store presets, and has only one
oscillator. On the other hand, its
modular structure makes for utterly
fresh and unique sounds.
Can it process audio?
As an audio
processing tool, the Dark Energy is
extremely deep. In addition to CV ins
and outs, an external audio input feeds
the filter and VCA sections.
Soft synths with great modulationoptions often get compared to modular
analog gear: “It’s got tons of LFOs! More
envelopes than you can shake a stick at!”
But have you ever actually played a real
modular synth? Have you experienced true
voltage control with patch cables and no
digital parameter encoding? Once you
have, you get spoiled. If you haven’t, it’s
probably because modulars can be esoteric
and expensive: You need multiple
modules to make familiar synth sounds, for
one thing. So when Doepfer announced
the Dark Energy — a self-contained baby
modular, with real patch cables, voltage
control, USB, and MIDI — we thought it
just might be the box that finally brings
modular synthesis to the rest of the keyboard-
playing world. In fact, it exceeded
those expectations.
VOICE STRUCTURE
The Dark Energy’s architecture is deceptively
simple: A single VCO feeds a
24dB-per-octave lowpass filter, which in
turn feeds a simple but clean VCA.
Throw in one envelope and two LFOs,
and to the casual observer, this seems
like a very basic box. Nothing could be
farther from the truth.
With a slew of control voltage and
audio jacks on the front panel, a small
array of MIDI-to-CV jacks on the back
panel, and a real analog signal path, this
synth can do tricks that even the hottest
programmable analog synths can’t quite
touch. Why? For one thing, the LFOs and
envelopes use entirely analog guts, delivering
ranges and fine-tuning control that
their digital counterparts simply can’t.
The trade-off is that you can’t store presets,
or sync modulation sources to the
tempo of something else, but you can
create sonic textures that are very unique
and surprisingly organic. The Dark
Energy breathes.
Oscillator. Octave range and tuning are
both givens here, so let’s delve into the
VCO’s niftier offerings. First up, the
waveforms are a continuous blend of variable-
width pulse wave combined with
either sawtooth or triangle. With the
saw/triangle switch in the off position, the
pulse wave is soloed. But how do you
hear the triangle or saw alone? Simply
set the pulse to 100:0 or 0:100 by turning
its width knob fully in either direction.
This is a fantastic approach that
should’ve been implemented in every
synth since time immemorial, as it gives
the oscillator far more tonal variety than
other methods.
The pulse width can be modulated via
either LFO 2 or the envelope for added
animation, and with some medium-rate
pulse width modulation, fat, chorus-y
leads can be whipped up with a minimum
of fuss. A frequency modulation knob
allows either LFO 1 or the envelope to
sweep the pitch for vibrato effects, dive
bombs, or Kraftwerkian thwips.
Filter. The Dark Energy filter sounds
really rich. It’s said that the circuit is
based on the Curtis chip, but there
seems to be some other voodoo going
on in here. With resonance at minimum,
the results are creamy, with a very Mooglike
low end warmth. This richness is fantastic
for bass patches. Cranking the
resonance all the way up gives the Dark
Energy an eerily Roland TB-303-ish kind
of feel: wet, squishy, and straight out of
an early ’90s rave.
There are two modulation knobs for
the cutoff — exponential and linear — that
make this VCF do far more than standard
fare. Exponential modulation, which is
Doepfer’s term for the type of filter modulation
found on most analog synths, can
be applied from either LFO 2 or the envelope.
This is the technique for creating classic wah-wah or juicy envelope
sweeps. At first, it seems a tad annoying
that you can’t apply both LFO and envelope
modulation to the filter, then you
glance at the row of jacks at the bottom,
and realize that yes, you can. Remember,
this is a baby modular synth!
The linear modulation knob controls
the amount of FM applied from the VCO.
I’ve always loved the warm complexity of
analog FM, and this implementation
doesn’t disappoint. “Wait a minute,” you
ask, “doesn’t FM mean you modulate one
waveform with another? How can the
Dark energy do it with only one oscillator?”
Easy. If you set the filter’s
resonance to maximum, it self-oscillates,
generating a sine wave — set the filter
cutoff to track the keyboard, and you
have an ideal carrier signal for FM. From
there, you can use the VCO as the modulator,
adjusting its frequency and waveform
to generate everything from bells
and chimes to ear-shearing nastiness.
Modulation. The modulation options
really bring the Dark Energy to life. The
two LFOs generate either a square or
triangle wave, and affect specific components
by default: LFO 1 modulates the
oscillator and the amplifier, whereas LFO
2 controls pulse width and filter modulation.
Here’s where the modularity of this
box comes into play. If you want to use
LFO 1 to control the filter cutoff or pulse
width, just grab a cable and patch it in.
Unfortunately, there’s not a similar option
for LFO 2, but that’s not a dealbreaker by
a long shot.
The LFOs get a lot more interesting
when you tinker with the range switch.
Each LFO has three modes: low,
medium, and high. Low mode is standard
synth fare, and great for sweeps, PWM,
and vibrato. Medium mode takes the LFO
rate into the lower audio range for FM
and ring mod type effects. High mode is
where the Dark Energy ratchets up its
sonic palette beyond other analog synths
we’ve heard. In high mode, the LFO rates
can reach well into the kilohertz range,
which means they’re not just modulation
sources, but oscillators in their own right!
Don’t believe me? Patch the output of
LFO 1 into the external audio in and listen
to it. We’re a tad bummed that
there’s no way to have the LFO rate track
the keyboard like a conventional oscillator,
but I digress.
Applying multiple audio-rate LFOs to
destinations like pulse width and filter
cutoff results in patches that only a full-on
modular (or a really sophisticated soft
synth) can touch. In fact, while [renowned
electronic music producer] Wolfgang
Gartner and I were putting the Dark
Energy through its paces at his studio,
we came up with incredible talkbox vocal
effects that Daft Punk would have been
proud of!
Envelope. This is a standard attackdecay-
sustain-release affair, with one crucial
distinction: another low/medium/high
switch. In low mode, the rates are slow
enough to create long, evolving drones.
In medium mode, it operates at speeds
similar to most classic synths. But in high
mode, the envelope is capable of
absurdly tight transients that make percussive
sounds, such as basses or things
you’d use in a tech or electro arpeggio, truly pop. This makes the Dark Energy
well-suited to analog drums and percolating
bass.
INTERFACING
For slotting this synth into your rig, there
are three options: USB, regular MIDI
input, and of course, control voltage (CV).
When driving the Dark Energy via USB, it
will even convert MIDI information from
your DAW to control voltages. Four CV
outs replicate the information for note,
pitchbend, velocity, and a single continuous
controller that defaults to the mod
wheel, but can be reassigned to any other
CC via the Learn button (see Figure 1 on
page 57). Using the included patch
cables, you can easily plug the velocity
CV out into the VCA in for velocity control
of volume, then plug the mod wheel into
the filter cutoff’s CV in for performance
control of sweeps and swells.
Since the note CV out adheres to the
classic one-volt-per-octave standard, you
can also use the Dark Energy to control
vintage gear. I tested this with my
beloved Roland SH-101 synth without a
hitch, sending MIDI data from Ableton
Live to the Dark Energy, then using its CV
outputs to drive the SH-101. From there,
I ran the SH-101 back into the Dark
Energy’s audio input, processing it
through the Doepfer filters and
envelopes, thus creating a hybrid modular
synth from the two. True confession:
This gave me goosebumps.
If you want to try this, note that some
vintage synths, such as the Korg MS-20,
don’t use the volt-per-octave standard.
You can still use the Dark Energy to control
parameter changes, but full-on musical
sequencing is just out of reach. So if
you’re planning to use the Dark Energy
as the nerve center for a vintage rig, a
little homework could save you a lot of
headaches down the road.
IN USE
I spent a solid month living with the Dark
Energy and never got bored with its
sound. More importantly, this box was a
source of inspiration every time I turned it
on. The external audio inputs let me
process and beef up the sound of other
vintage gear, like my Sequential Circuits
Prelude and even my Yamaha TX81Z
module, running them through the filters
and using gratuitous amounts of audiorate
modulation with amazing results.
Until now, I’d been using my SH-101’s
internal sequencer for cycling riffs, but to
be candid, slicing or looping the results
was pretty darned tedious. Being able to
directly sequence my 25-year-old piece
of history from Ableton Live has added a
slew of new colors to my studio palette.
We’d known that the Dark Energy had
this feature, but in practice, the results
were nothing short of inspirational — a bit
like running into a long- lost high school
crush and discovering that you have even
more in common now.
I was so jazzed about the box that I
started calling my analog-addicted
producer buddies and raving about its features
and sound. After a day in the studio
with the Dark Energy, Wolfgang Gartner
said, “I got completely lost in this box and
generated some of the coolest sounds and
patterns I’ve ever heard. I have to get one.”
There’s even an arpeggiator lurking
within the Dark Energy, but to be candid,
it’s quite fiddly to configure, and with
USB and MIDI control letting you play
notes from a sequencer or keyboard, its
inclusion isn’t all that enticing. Still, it’s
nice to know it’s there.
CONCLUSIONS
We’re completely sold on the Doepfer
Dark Energy. It’s a perfect first synth for
producers looking to get more deeply
into analog. It’s also an indispensable
addition to studios that already have a
few vintage or current analog synths laying
around. If you’re used to modern keyboards,
the only thing you might miss is
stereo output; more likely, you’ll be having
so much fun creating sounds that
you won’t care. The Dark Energy is
utterly unique, completely useful, and so
full of inspiration that I simply can’t bear
to part with it, so I’m purchasing my
review unit. Doepfer has a Key Buy-winning
hit on their hands, and considering
how back-ordered this box is right now,
you might want to get in line. You won’t
be disappointed.