with a Bazooka BTA6100 amplified subwoofer, we help fix one of the biggest weaknesses
of the new Toyota Prius.
The SAS Bazooka BTA6100 package
all the accolades bestowed on the new Toyota Prius, one would think the carmaker
hasn't overlooked any details in designing this most high tech of high tech production
cars. The car certainly has more than its share of gee-whiz technology: Its super-quiet
operation during full-electric mode, its coolant thermos that keeps the gas engine
warm for three days, the locks that detect your presence as you approach the car
(the optional SmartKey), a stability control that purports to detect when you're
oversteering - and self-corrects the wheel angles via its electronic steering
mechanism (S-VSC), the continuously variable automatic transmission, and (in Japan
only) an automatic self-parallel parking option. That's a pretty impressive list.
Low Tech Fi in a High Tech Car
With all this technology going
into this car, it's perplexing how mediocre its sound system is. The Prius can
be had with one of two systems: A "premium" six-speaker system with separate woofers
and tweeters in the front doors and full-range speakers in the rear doors; or
an optional JBL nine-speaker system, with a center voice speaker on top of the
dash and two-way woofers and tweeters in each of the doors.
system offers anything approaching state-of-the-art sound. Curiously, the JBL
system is not all that much better than the standard "premium" system. The extra
speakers in the JBL system go toward speech articulation (the center dash speaker
is mainly for the talking navigation system) and tweeters for the rear passengers.
Neither system has a subwoofer.
As can be expected, what's missing from
both systems is any semblance of real bass from the speakers. Consequently, the
sound is rather shallow - sort of like what you'd expect from a small compact
As it turns out, the sound system ranks among the top
(albeit few) complaints of discriminating Prius owners (the other complaints being
the alloy wheels that look like plastic wheel covers and not being able to match
the EPA gas mileage ratings).
room for improvement in the Prius
Addressing The Problem
To address the sound system problem,
Southern California's online automotive magazine, turned
to its sister publication, LA Audio File.
Both publications have staff members with considerable experience - i.e., the
former technical director for Nakamichi USA, an audio equipment reviewer for The
Sensible Sound, members of the Audio Engineering Society, and an OEM engineer
for the Mark Levinson and Pioneer systems that go into the Lexus and Scion line
of vehicles, respectively.
For this project, we couldn't help noticing
that one of the popular factory-authorized optional accessories for the Scion
is the Southern Audio Services (SAS) "Bazooka" subwoofer. Our audiophile panel
came to a consensus: Given the physical similarities between the four-door hatchback
Scion and the four-door hatchback Prius, fitting an amplified Bazooka subwoofer
to the latter is a logical choice.
Withstanding the Test of Time
SAS is the company that popularized the bass tube subwoofer design (they
hold the patent on it), and they've been developing, refining, and building the
Bazooka subwoofer for over twenty years. Because Bazooka has withstood the test
of time (and its status as an official Toyota supplier brand), we chose to go
with an amplified Bazooka subwoofer for our Prius project car.
the little-known beliefs held by some Bazooka specialists is that the smallest
units with the 6-1/2 inch driver have the best bass articulation of the bunch.
The bigger units offer a bigger sound. However, if you're after the cleanest bass
reproduction, have a relatively small vehicle, and don't have a need to really
crank up the volume, consider one of the small Bazookas. We did just that in choosing
The BTA6100 is one of two amplified Bazooka bass tube subwoofers
with a 6-1/2 inch driver (the other being the BTA6200). Both the 6100 and 6200
have frequency responses that go down to 39 cycles per second (right about the
range of the lowest note of a stand-up acoustic bass instrument). Where the two
significantly differ is in power output (100 watts for the 6100 and 200 watts
for the 6200), crossover range (fixed at 85 hertz for the 6100, variable from
80-250 hertz on the 6200) and price ($199.95 versus $279.95).
about installing the unit ourselves. After all, there are some very capable Prius
teckies doing everything from installing full-electric (EV) buttons to back-up
cameras for their cars. However, that doesn't describe most Prius owners, and
taking apart the Prius dashboard is not something we want to wish on anyone. In
the end, we opted to have the installation done for us.
Circuit City Roadshop personnel
Serrano, Incledon & Medina
Just What We Needed
We chose to go with Circuit City. First of all, because they're national
in scope, and reader can replicate our results. Second, they carry the Bazooka
line, and are familiar with its installation. Last, but not least, Circuit City
charges a flat rate of only $55.99 to install this subwoofer into the Prius (in
the Los Angeles area - elsewhere it's $55.99-60.99, depending on the market) .
Given the myriad of dashboard parts that require removal to get to the central
sound system assembly, it's a pretty reasonable price for the installation (check
out Metro Toyota of Cleveland's Prius
XM Radio installation instructions to get an idea of what's involved).
Location, Location, Location
Armed with an SAS Bazooka BTA6100
powered subwoofer, we took our project car to Circuit City's new Roadshop facility
in West Covina. There, we met sales and installation manager Javier Serrano, who
went to great lengths to discuss the pros and cons of various installation locations
for the Bazooka.
We considered the cavity under the trunk area, but the
Roadshoppers thought that'll result in a muted sound. Also considered was the
area above the lid on top of the cavity, which will make the subwoofer unit easily
removable. Bazooka's standard recommendation is to have the unit mounted longitudinally
and firing into one of the rear corners of the trunk cavity. "We recommend that
orientation because it works in every vehicle we've encountered," says
SAS Bazooka Product Specialist Derek Tircuit. "It's almost like an eternal truth
that we can pass along. However, other orientations will work."
Serrano lobbied for the area just behind the rear seats, but that's just
above the hybrid car's battery pack. Roadshop installer Michael Lopez disassembled
the trunk area, however, and found that the battery pack is protected by dual
barriers. Thus, the installer can affix the subwoofer onto the first surface without
penetrating the second barrier that protects the battery pack. The location also
places the subwoofer away from the trunk opening, making it less obtrusive in
day-to-day use. Most importantly, it allows the unit to be adjacent to two surfaces
(the trunk floor and the rear of the seats, while firing into a corner of the
trunk cavity (corner loading is strongly recommended by Bazooka). We went with
the Roadshop recommendation.
The end result certainly looks attractive.
All the wiring is neatly tucked away and hidden from view. In order to avoid having
to splice too many wires, Circuit City used Bazooka's optional 1761 interface
harness, which fits certain model Toyotas. In the Prius, Lopez switched the remote
wire that turns on the amplifier over to the the accessory lead. "Otherwise, the
harness works fine," says Lopez. Circuit City installed the subwoofer with the
optional SAS chrome mounting rings, which adds some nice contrast to the black
Bazooka. In the event the seats need to be folded down for expanded cargo use,
a simple Allen wrench will disengage the subwoofer tube. For those who stick with
the tie-down straps that come standard with the subwoofer package, it's even easier.
The Bazooka is neatly tucked away
What About the Sound?
In a word: Transformed. The subwoofer
does what it's suppose to do. The bass enhancement on pop recordings is subtle,
with great extension where the material actually has extension. On certain concert
organ or electronic music, you feel - mot merely hear - the bass registers. When
the musical signal has no bass, the subwoofer stays out of the way.
More importantly, the midrange is now dramatically more open sounding. With
the Bazooka's crossover network cutting off the lower bass from the midrange-woofer
drivers, they are free to reproduce the midrange without having to do double duty
on the bass. The result is a cleaner sound overall. The Prius now has a sense
of transparently and immediacy that is lacking in the factory system.
On a few recordings, we detect a slight trough in the mid to upper bass. This
is more a fault of the factory woofers, in that they just don't product much sound
in that region. We have the BTA6100, which has a crossover network fixed at 85
hertz. We suspect that this is not even a factor with the more expensive BTA6200,
with its variable frequency crossover network. In any event, it's only noticeable
on a few recordings - and subtle use of the bass control on the factory system
mitigates this anomaly.
Keep an Allen wrench handy for quick removal
The other thing we notice is that the subwoofer reveals the variations from
recording-to-recording much more readily than the stock system. The Bazooka has
a subwoofer output control, so you can adjust the amount of volume that the subwoofer
puts out relative to the satellite speakers. However, while the output can sound
just fine with one recording, another recording may sound like it has a bit too
much bass. Again, the Prius' bass tone control (which thankfully affects the midrange
minimally) is quite helpful. What will help more is a remote subwoofer output
control. Such a control is, in fact, an optional accessory for the Bazooka.
The Bottom Line
Music is now more enjoyable in the Prius.
There is a sense of realism to the music that transforms what was once ordinary
to sound that is now extraordinary. The scale of sounds coming out of the system
is larger, more life-like. Playing "Pops Hoedown" off of the Telarc Round-Up
CD with the Cincinnati Pops Orchestra yields a palpable "you are there" quality.
The same quality is heard and felt when playing "Take Five" off of the Columbia
SBM Master Sound CD of the Dave Brubeck Quartet's Time Out. Play No Doubt's
"Hella Good" (The Singles 1992-2003, Interscope Records), and all hell
breaks loose as the Prius-Bazooka system belts out some clean, powerful rock n'
We find no adverse affects to the addition of the subwoofer
- no detectable impact on battery drain, battery charging, or fuel economy. We
do find ourselves looking forward to hearing the audio system in the Prius - something
we never did before. Trying out various CDs, we are continually amazed now much
better things sound - now that the Prius is armed with a Bazooka.
- Roy Nakano
Editors' Note: This article also appears
in L.A. Audio File's sister publication, LA Car, where it is entitled,
"Project Prius: Breaking The Sound Barrier." LA Car is a World Wide Web
journal of Los Angeles and its car culture. To view LA Car, aim your Web
browser to www.lacar.com