At the heart of Cannibal Corpse’s bone-crushing
bass sound is a small pedal
called the Darkglass Electronics B3K
MicroTubes Overdrive. Its big brother, the
B7K, offers even broader tones.
This past summer I had the pleasure of
attending a Cannibal Corpse soundcheck
at the Starland Ballroom in New
Jersey. I was there to interview guitarist Rob
Barrett, who recently came onboard as a
Yet what really got my attention during
the band’s soundcheck was bassist Alex
Webster’s tone, which offered massive low
end, tight, punchy midrange, and just the
right amount of overdrive to make things
mean without sounding sloppy or overly
synthetic. To sum things up, it was nothing
short of monstrous—apropos for a band
like CC, I suppose.
I was able to get some face time with
Alex and he gave me a quick rundown of
his rig. In addition to his signature Spector
Bass and wall of SWR amplifiers, he gave
a lot of the credit for his bone-crushing
sound to a tiny device nestled snugly in his
pedalboard: the Darkglass Electronics B3K
A small boutique builder out of
Finland, Darkglass specializes in bass
effects and the B3K MicroTubes is their
flagship model. A big buzz has been building
around this little box, and with good
reason. Simply put, this pedal is all killer
and no filler.
Housed in a small and simple package,
the B3K offers the standard drive and level
controls you’d expect on any OD pedal. In
addition, it sports a dry blend control—an
essential tool to achieve distorted bass
tones without losing low-end punch.
The B3K also features two “secret
weapon” switches: Grunt is a 3-way pregain
bass boost that allows you to select
the amount of low end to saturate. Each
position sounds great in its own right, with
“fat” being my favorite of the bunch. The
attack switch is an ultra-high boost that can
add some treble grit to your tone—perfect
for delivering extra presence to fingerstyle
playing or warming up edgy pick work.
With these simple controls, the pedal
delivers a vast array of boosted and overdriven
bass tones. While I found myself
steering more towards the fully saturated
settings, the B3K is equally adept at providing
milder overdrives or just a slight hint of
tube-like warmth for less aggressive applications.
I was pleased to discover that the
B3K lived up to the hype and I had great
fun conjuring brutal, Webster-esque bass
tones in the comfort of my home and with
my standard bass-and-amp setup.
Intrigued, I did more research and found
that the B3K has a big brother, the B7K
MicroTubes. The B7K boasts the same
drive section as the B3K, but with the addition
of a 4-band EQ and a direct output,
taking it into the realm of bass preamp/
DI that has been ruled by the Tech 21 Bass
Driver DI for well over a decade.
I’ve been a big advocate of the T21 bass
boxes since they released the original Bass
Driver back in the early ’90s. I’ve done
many gigs and recordings with the Bass
Driver, yet I always felt that the lack of a
midrange knob limited the variety of tones
you could get from it. Likewise, I always
found myself longing for a bit more saturation
from the drive control to take me into
all-out distortion territory.
Darkglass obviously took these issues
into consideration when they designed the
B7K. In addition to the grunt and attack
switches of the B3K, it’s also equipped with
bass, treble, low-mid, and hi-mid controls
to help sculpt your EQ. When shaping
bass sounds, I find dual mid-band EQs
essential, so these latter two knobs were a
welcome feature. Furthermore, the B7K
offers more drive and output level than the
reigning champ, allowing for a much wider
variety of saturated tones.
In back-to-back comparisons of these
two pedals, I found the B7K to be more
transparent and offer a less compressed
sound than the T21 Bass Driver. This
allowed me to create subtle variations in the
degree of breakup just by changing playing
dynamics. While dialing in a sound
took longer on the B7K, the payoff was a
broader palette of tones.
Considering that the B7K is more than
twice the price of the legendary Bass Driver,
you really have to weigh these pros and cons
carefully before making a purchase decision.
However, if you’re a player who demands
the ability to fine-tune your tone or simply
needs a wider variety of tonal options, then
the B7K is worth every penny and more.
Darkglass recently cut a production deal
with 3Leaf Audio, so all Darkglass products
are now handmade in the USA with shorter
lead times and lower prices. This leaves
Darkglass free to concentrate on design
work, and yes, they’re coming out with a
series of effects for guitar very soon!
If the MicroTubes models are any
indicator of what we can expect from this
talented little company, I think we’ll be
hearing a lot more about Darkglass effects
in the future. Until then, visit their website
at darkglasselectronics.com to see and
hear what the MicroTubes might do for
your bass tone.
is the president
and founder of Godlyke, the U.S.
distributor for many well-known
boutique effect brands, including
Maxon, Guyatone, EMMA, and