Listen:
By definition, “streamlining” refers to
the process of making something simpler
or more efficient. And this certainly
appears to be the direction behind the new
Streamliner amps, a series of class-D bass
amps from Jeff Genzler and his team at
Genz Benz. While other amplifiers in the
Genz Benz line offer tone-tweaking options
like FET and tube preamps, active parametric
equalization, and global signal-shaping
circuitry, the Streamliner holds true to its
name with a simple, user-friendly control
configuration and an all-tube, class-A preamp
section.
Brick House
The Streamliner 900 has a very different look
than its class-D cousins in the Genz Benz
Shuttle series. The chassis is aesthetically pleasing,
with extruded aluminum sides that convey
a sense of durability. The knobs feel substantial,
and their smooth rotation contrasts with the
finer movements of Shuttle pots.
What makes the Streamliner so unique
lurks within its clean, well-designed interior.
Removing the top plate reveals a six-stage, all-tube
preamp with three 12AX7 tubes—one
for Gain, one for the Bass and Treble controls,
and one for the active Mid EQ. Genz
Benz also integrated its proprietary Heat
Abatement Technology, which effectively—
and just as importantly,
silently—cools the
unit during operation. Another unique feature
is the Streamliner’s 3 Dimensional Power
Management (3DPM) technology—a limiter
that compresses lower frequencies while leaving
upper mids and highs untouched. This
creates a feel similar to tube compression
while protecting the class-D power amp.
About Face
The Streamliner’s front panel is simple and
straightforward. The 1 MΩ input matches
well with high-impedance pickups—
whether they’re in a passive electric bass or a
pickup-equipped upright. Next to the input
and conveniently placed Mute switch, the
preamp section has a Gain switch for overdriven
tones. Used in conjunction with the
Gain and Volume knobs, it enables you to
achieve a variety of tones—from clean tube
warmth to a nasty snarl.
A first for Genz Benz is the influence
of the Bandaxall topology on the Bass and
Treble shelving filters. This creates smooth
enhancements to the lows and highs without
dramatically affecting other frequencies.
And continuing with the streamlining philosophy,
Genz Benz simplified the midrange
EQ by allowing the user to cut or boost
within three frequency centers—220 Hz,
600 Hz, and 2.5 kHz. These commonly
used frequency points allow you to add
some very precisely tuned punch and presence
to your tone.
Rounding out the front panel is a Master
knob, and an array of LED indicators confirming
power delivery (blue), signal peaking
(amber), and Protect mode (red). When
you turn on the Streamliner, the red LED
also indicates that Warm-Up mode is active
and allowing the tube preamp to bias and
stabilize properly before operation.
The rear panel has common features
like dual Neutrik speakON connectors, an
effects loop, and a DI. Genz Benz also
included an auxiliary input for a
CD or MP3 player, a Tuner Out, a
Headphones jack that you can use
without a speaker load, and a voltage
selector for the world traveler.
Wielding the Hammer
My initial impressions of the
Streamliner 900 were based on a
comparison with its counterpart, the
Genz Benz Shuttle 9.0. Setting both amplifiers
flat and pairing them individually with
a 4x10 cabinet, it was immediately clear
these two amps were very different animals.
The Streamliner 900 provided a thick tone
and solid attack, and with each pull of the
strings I could feel the weight of each note.
The Shuttle had a more modern sound
with clarity and response, but it couldn’t
quite match the warmth and heft of the
Streamliner. As a sonic weapon, the Shuttle
is more like a sword, while the Streamliner
is definitely a war hammer.
I used four basses to assess the versatility
of the Streamliner 900—a 1964 Fender Jazz
bass, a 5-string Music Man StingRay, a Bill
Nash P-style with flatwound strings, and
a carved German upright with a Fishman
BP-100 pickup. I paired the Streamliner
with a variety of 4x10, 1x12, and 1x15 cabinet
configurations. After setting the Gain
and Volume knobs to minimize peaking, I
played the basses with the EQ set flat. Then
I tested how various adjustments to certain
frequencies enhanced the basic sound.
The J bass retained its clear, articulate tone,
and soloing on the bridge pickup sounded
round and burpy. Boosting the mids at 220
Hz gave the ’64 J’s aging pickups some extra
punch. The 3DPM feature was a big benefit
when slapping and popping on the StingRay,
because it kept the bottom tight and maintained
the bright transients of that modern
classic bass. The Streamliner also handled the
5-string Music Man’s B string with good definition.
I was also impressed with how well the
Nash P bass matched with the Streamliner—
pairing the amp with a 1x15 cabinet evoked
enough old-school tone to bring out my best
possible James Jamerson impressions. I was
also able to capture the classic P-bass growl by
backing off the Bass control and boosting the
mids at 600 Hz.
With all the electric basses, I engaged the
Gain switch and experimented with varying
amounts of overdrive. The switch is useful
in adding an edge or a bit of hair to the
tone, but the lack of power tubes seemed to
keep the Streamliner from completely hitting
the mark on classic overdrive sounds.
While I was pleased with how the
Streamliner handled electric basses, I was most
impressed when I plugged in my upright. Set
flat, the amp brought out the wood of the
instrument, as well as a tight, low-end punch
on every note. And it was simple to temper
the highs of the Fishman pickup by cutting
the well-voiced Treble EQ. On a recent jazz
quintet gig with the Streamliner, some listeners
were surprised to learn my bass was amplified—
the tone was that pleasing and natural.
I have tried numerous amps in search of these
qualities, and the Streamliner 900 has quickly
joined the group of rigs that fit the bill for me
when gigging with an upright bass.
Power Play
Besides pumping out great tones, the
Streamliner delivered an impressive
amount of power for its 6 1/2-pound
package. Rated at 900 watts at 4 Ω (500
watts at 8 Ω), the Streamliner held its
own against volume-happy guitarists and
bombastic drummers. It also blended in
well with jazz combos and big bands. If
you don’t need that much power, check
out the Streamliner 600, which uses the
same preamp but is rated at 600 watts at
4 Ω (375 watts at 8 Ω).
The Verdict
The Streamliner 900 is a solid option for
great tube tone in a small package. Its simplicity
and nod to classic bass designs make
it a welcome addition to the Genz Benz
family. Their engineers have designed a
musical EQ that makes it easy to solve tone
issues in live performances. While it’s not
the lightest or smallest amongst the many
class-D amps on the market, the Streamliner
makes up for it with its durable chassis and
well-built components. So if you’re seeking
a versatile, powerful, extremely portable
bass head, the Streamliner 900 is well worth
checking out.
Buy if...
you seek portability and tube
tone that works well with acoustic
and electric basses.
Skip if...
you prefer modern tones or only
an all-tube amp will do.
Rating...
