JBL GTO804 User manual

THANK YOU
for purchasing a JBL®Grand Touring®Series subwoofer.
Subwoofer installation requires woodworking skills and some
experience in disassembling and reassembling automotive
interiors. If you lack the tools or necessary skills, have your
subwoofer installed by an authorized JBL dealer.
GRAND TOURING®
SERIES
GTO804
GTO1002D
GTO1004D
GTO1202D
GTO1204D
GTO1502D
GTO1504D
car audio subwoofer
owner’s manual

CHOOSING AN ENCLOSURE
WARNING: Playing loud music
in an automobile can permanently
damage your hearing as well as
hinder your ability to hear traffic.
We recommend listening at low
levels while driving. JBL accepts no
liability for hearing loss, bodily injury
or property damage resulting from
use or misuse of this product.
Grand Touring Series subwoofers
are optimized to perform best in
small, sealed, vented and prefabri-
cated bandpass enclosures. While
infinite-baffle mounting of GTO subs
is possible, power handling will
be greatly compromised because
there’s no enclosed volume of air
to prevent the speaker’s cone from
moving past its limit. For this reason,
we do not recommend infinite-baffle
mounting for GTO subwoofers.
You should choose the enclosure
you will use based on the type of
music you listen to, how much
amplifier power you will use for the
subwoofer and how much space
inside the vehicle you can devote
to a subwoofer enclosure.
Because a sealed enclosure
provides the most control over
the woofer’s movement, a woofer
mounted in a sealed enclosure will
handle more power than a woofer
mounted in another enclosure type.
Sealed enclosures provide more
accurate sonic reproduction than
other enclosure types when
mounted inside a vehicle, so they
are well-suited to all types of music.
Sealed-enclosure construction is
straightforward and there are many
prefabricated sealed enclosures
available. An optimum sealed
enclosure is always smaller than
other types of enclosures optimized
for a particular speaker, so they
require the smallest amount of
space inside the vehicle.
Vented enclosures provide better
efficiency in the 40Hz – 50Hz range
but this efficiency comes at the
expense of sound in the lowest
octave (below 40Hz) and at the
expense of some control and power
handling at the lowest frequencies.
If you are using a small amplifier,
avented box will provide more
perceived bass output from less
power. Vented enclosures are also
well-suited to a variety of music
types. Because vented enclosures
require the volume of the enclosure
and the size of the port to have
a specific relationship with the
characteristics of the woofer, the
enclosure must be built exactly to
the specifications provided. While
there are some prefabricated
vented boxes available, matching
aprefabricated box to a particular
woofer is difficult. If you wish to
use a vented enclosure, we strongly
recommend having your authorized
JBL dealer build it or verify that your
design is correct if you wish to build
it yourself. An optimum vented
enclosure is always larger than the
optimum sealed box for the same
woofer and will require more space
inside the vehicle.
Bandpass enclosures often provide
the most output available from any
amplifier and subwoofer combination
at the expense of sonic accuracy.
If sheer SPL (sound-pressure level)
is what you desire most, choose a
bandpass enclosure. Bandpass-
enclosure design is very tricky and
the aid of a computer and enclosure
design software is necessary. If you
are an experienced installer or have
some woodworking experience,
you may wish to build the bandpass
enclosure described in the enclosure
design sheet included with this
woofer. Fortunately, there are many
prefabricated bandpass boxes
available and they are all optimized
to extract the most output possible
from any woofer. Bandpass
enclosures can be quite large and
may require a lot of space inside
your vehicle.

JBL Grand Touring Series
subwoofers are available in two
different configurations: as dual
4-ohm voice coils or as dual 2-ohm
voice coils. Depending on the
amplifiers you are using, you may
use GTO subwoofers in singles or
multiples to maximize the power
available from your amplifiers. To
achieve the maximum amplifier
output possible, you should design
aspeaker system that provides
the lowest impedance that your
amplifier will drive safely. When
designing a subwoofer system,
consider the following rules:
1. Do not mix different subwoofers
or enclosure types in the same
system. Subwoofers being used in
the same enclosure or powered
from the same amplifier should
be identical models. Mismatched
woofers and enclosures can
result in poor performance from
your subwoofer system.
2. You may connect the coils of a
dual-voice coil woofer in series,
but we recommend that you avoid
connecting separate woofers in
series.
3. You must use both coils of a dual-
voice coil woofer connected
either in series or in parallel.
4. Most amplifiers deliver exactly
the same amount of power
bridged into a 4-ohm load
as they do running a 2-ohm
stereo load.
To design a subwoofer system
that maximizes available amplifier
power, keep the following rules
in mind:
1. The total system impedance
of woofers in parallel can be
calculated using the formula:
Impedance = 1
1+1+1...
w1w2w3
where w is the nominal
impedance of the woofer.
2. The total system impedance
of voice coils (or woofers) in
series can be calculated using
the formula:
Impedance = w1+ w2+ w3...
The diagrams at right show parallel
and series speaker connections.
NOTE: There are two jumpers
supplied with the woofers to make
connections easier.
Figure 1. Parallel connection
NOTE: The GTO1004D, GTO1204D
and GTO1504D come with both
jumpers installed for a parallel
configuration.
Figure 2. Series connection
NOTE: The GTO1002D, GTO1202D
and GTO1502D come with one
jumper installed for a series
configuration.
CONNECTING YOUR SUBWOOFER TO YOUR AMPLIFIER

SPECIFICATIONS
GTO804 GTO1002D GTO1004D GTO1202D GTO1204D GTO1502D GTO1504D
8" Single 4-Ohm 10" Dual 2-Ohm 10" Dual 4-Ohm 12" Dual 2-Ohm 12" Dual 4-Ohm 15" Dual 2-Ohm 15" Dual 4-Ohm
Subwoofer Subwoofer Subwoofer Subwoofer Subwoofer Subwoofer Subwoofer
Power Handling, RMS 200W 250W 250W 300W 300W 300W 300W
Power Handling, Peak 800W 1000W 1000W 1200W 1200W 1200W 1200W
Sensitivity (2.83V/1m) 91dB 91dB 91dB 93dB 93dB 93dB 93dB
Frequency Response 30Hz – 400Hz 25Hz – 400Hz 25Hz – 400Hz 23Hz – 400Hz 23Hz – 400Hz 23Hz – 400Hz 23Hz – 400Hz
Impedance 4 Ohms 4 Ohms/1 Ohm 8 Ohms/2 Ohms 4 Ohms/1 Ohm 8 Ohms/2 Ohms 4 Ohms/1 Ohm 8 Ohms/2 Ohms
Mounting Depth 4-3/8" (112mm) 4-9/16" (116mm) 4-9/16" (116mm) 5-1/16" (129mm) 5-1/16" (129mm) 5-5/8" (143mm) 5-5/8" (143mm)
Cutout Diameter 7-3/16" (183mm) 9-3/16" (234mm) 9-3/16" (234mm) 11-3/16" (285mm) 11-3/16" (285mm) 13-7/16" (342mm) 13-7/16" (342mm)
Overall Diameter 8-1/4" (210mm) 10-3/8" (264mm) 10-3/8" (264mm) 12-7/16" (316mm) 12-7/16" (316mm) 15-1/16" (383mm) 15-1/16" (383mm)
Avalid serial number is required for warranty coverage.
Features, specifications and appearance are subject to change without notice.
These products are designed for mobile applications and are not intended for connection to the mains.
JBL CAR AUDIO SUBWOOFER SYSTEMS