JBL 600GTI User manual

600 MANUAL/vs2.QXP 7/28/98 11:47 AM Page 1

Table of Contents
Welcome to Club GTi ............................................3
About this Manual .................................................3
Autosound at its Best ............................................3
Designing Your System.........................................4
Component Placement..........................................4
Installation Warnings and Tips ..............................5
Mounting Instructions............................................5
600GTi Mounting...................................................6
Wiring....................................................................7
System Connections .............................................7
Speaker Break-In ..................................................8
A Note on Power Handling....................................8
In Case of Difficulty ...............................................9
Specifications......................................................10
Thiele-Small Specifications .................................11
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Welcome to Club GTi
Thank you for purchasing the finest
automotive Component woofer/midbass
transducer JBL has ever produced. As a
GTi Competition Series owner, you are a
member of a select group of people who
enjoy the most advanced mobile audio
products available. We call this group
“Club GTi.” By sending in the customer
information card, which you will find
attached to your warranty, we will
automatically register you as a Club GTi
member which will give you access to
exclusive Club GTi apparel and other
special offers we will make available from
time to time. We suggest you fill the card
out at your earliest convenience.
Also, be sure to save your sales
receipt in a safe place. It will be necessary
to use this document as proof of purchase
in the event that you ever need warranty
service. It is also useful for insurance
purposes and for establishing value when
you re-sell your vehicle.
About This Manual
Because of the performance capability
of your GTi Competition Series product,
and the variety of potential system
configurations, we strongly recommend
that you have the system professionally
installed. You will also get a better
warranty if your equipment is pro-
fessionally installed by an authorized
GTi dealer and you have your warranty
card stamped. This manual provides
information on installation and usage to
help a skilled technician get the most from
your GTi Competition Series product. This
manual does not cover basic information
about installation which is common
knowledge to a professional installer,
except for information which is unique to
the 600GTi Woofer/Midbass.
If you feel you possess the necessary
skills, and prefer to install the equipment
yourself, this manual will provide you with
the necessary specifics to properly use the
600GTi in typical installations. Consult
your JBL dealer, or a qualified technician,
for more information.
Autosound at its Best
The 600GTi Woofer/Midbass is built to
meet the same rigorous standards of con-
struction and performance that have long
established JBL's renowned home and
professional speaker systems. The 600GTi
Woofer/Midbass incorporates a high poly-
mer laminate pulp cone which is especially
suited to the unique acoustic and environ-
mental requirements for an automotive
woofer/midbass unit. The 600GTi has
been engineered to provide excellent
power handling, optimum transient attack
and balanced frequency response.
The 600GTi Woofer/Midbass uses a
cast frame to secure the powerful Barium
Ferrite Magnet based motor structure.
The rigid cast frame prevents resonance
and flexing in the frame thus reducing
distortion. In the 600GTi, the high con-
centration of magnetic power generated
by the large motor structure is coupled to a
2" Edge-wound Aluminum Wire High
Temperature Fiberglass Voice Coil. This
powerful motor structure delivers dynamic
midbass while its large diameter and
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fiberglass former assure extremely high
thermal power handling.
A high polymer laminate cone is used
because of its excellent combination of
high stiffness and low mass. This lets the
600GTi reproduce the powerful attacks of
percussive bass with immediacy and
impact.
The cone motion of these high
excursion designs is controlled by an
Aromatic Polyamid Fiber spider. Because
it is seven times stronger than con-
ventional spiders, this new material is able
to control the extreme motion of the cone
while maintaining musical accuracy with
incredible ruggedness.
What does all this technology add up
to? A driver with smooth frequency
response, excellent transient response,
and high output capability all in a rugged
package. The result is exceptionally
dynamic and accurate music reproduction
over the bass and midbass frequency
range that cuts through road noise and
provides a solid musical foundation.
Designing Your System
The overall quality of any system
design is a result of how well all of the
components work together, not just the
result of the performance of any one
component. JBL GTi Series Tweeter,
Woofer/Midrange, Coupled Component
and Subwoofer Transducers are the ideal
companion products to your 600GTi
Woofer/Midbass. Each of the GTi
Competition Series products are designed
to complement the others to provide the
highest performance with the simplest and
most predictable system design. To use
the 600GTi as the woofer or midbass
transducers in a high quality system, we
recommend you use a high quality active
crossover such as JBL's GTX47, GTX4 or
GTX2 to provide optimum matching to
your subwoofer or midrange loudspeaker.
If you prefer passive crossovers, we
recommend that you use only high quality
audiophile grade film-type capacitors and
low DCR inductors to get the most out of
your system. The most popular system
configuration is a hybrid using an active
crossover for the subwoofer to woofer/
midbass crossover point, a second active
crossover for the midbass to midrange
crossover, and a passive crossover for the
midrange to tweeter crossover. Your GTi
Competition series dealer is uniquely
qualified to help guide you on the best
system configuration for your needs.
Component Placement
The location of each of the
loudspeakers plays a vital role in achieving
proper frequency response and spacious
imaging. Because the 600GTi Woofer/
Midbass have an extremely wide and
smooth dispersion pattern, excellent
performance may be achieved in any
vehicle. Due to the wide variety of
vehicles, there is not one “right” way to
locate the 600GTi, however knowledge of
the following considerations will help you
get the most from your system:
1. The most spacious stereo image is
achieved when the speakers are placed
as wide apart as possible. The lower
the crossover frequency is set, the
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less sensitive your ear will be to the
exact position of midbass frequencies.
The best system imaging is usually
achieved when the major portion of the
musical spectrum is handled by the full-
range system and the midbass drivers
only reproduce the frequency range
below 200-250Hz. This makes the
exact location of midbass speakers less
critical than the mid and high frequency
components in the system.
2. The best center image will be achieved
when the distance from the left speaker
to your left ear is as equal as possible
to the distance from the right speaker
to your right ear. This is most easily
achieved by placing the 600GTi as far
forward as you can.
3. The best system integration is achieved
when the 600GTi is mounted close to
the midrange. Installing the midrange
close to the 600GTi helps smooth the
transition from midbass to midrange at
the crossover point.
4. You will get the best frequency
response when the path from the
speakers to your ear is unobstructed.
5. Because of the high acoustic energy
capability of the 600GTi, they must be
securely mounted in a rigid panel which
is free from resonances, rattles and air
leakage.
6. Due to the low frequencies reproduced
by the 600GTi, an enclosure will
enhance performance when it is
possible to accommodate one in the
available space. Use the Thiele-Small
specifications to design a sealed or
vented enclosure using standard
formulas. Thiele-Small specifications
are listed in the specifications section of
this manual.
Installation Warnings and Tips
• Be careful not to cut or drill into fuel
tanks, fuel lines, brake or hydraulic
lines, vacuum lines or electrical wiring
when working on your vehicle. Inspect
behind panels before you cut or drill.
• Be sure to check for clearance of
window, cranks and linkages when
mounting speakers in door panels.
• Do not use the speakers unmounted.
Failure to securely mount this product
could result in damage or injury,
particularly in the event of an accident.
• Although the materials used on the
600GTi are inherently water resistant,
do not mount the speakers where they
will get wet.
• Always disconnect the ground wire
from the battery before doing any work
on the vehicle.
Mounting Instructions
Pick a mounting location after reading
the recommendations in the Component
Placement section of this manual.
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600GTi Mounting
Mounting the Speaker
1. Use the grill included in the package to
mark the location of the four screw
holes and the speaker cutout holes
(cutout hole size listed in Specifications
section). Before cutting or drilling make
sure that there are no car components,
electrical wiring or any other items that
could be damaged.
2. Cut out the speaker hole at the
mounting location and drill the four
marked holes with a 1/8" (3mm) drill.
3. Run speaker wire to the hole location,
making sure that either an active or
passive crossover is connected to the
speaker.
4. Connect the speaker wire to the
speaker by either soldering (preferred)
or using crimp terminals. The 600GTi
uses a .205 flat blade terminal for the +
connection and a .110 terminal for the –
connection.
5. Mount the speaker to the hole location
using four #8 x 11/4" screws as shown in
FigureA.
6. Push the metal grille down onto the
grille frame, making sure to align the
logo as desired.
Note: The metal grille is designed so
that it can be covered with grille cloth if de-
sired. Simply remove the metal grille from
the grille frame as shown in Figure A. Then
use spray adhesive to glue and wrap the
grille cloth to the metal grille. Push the
metal grille with cloth back in the grille
frame. For even better interior matching it
is also possible to use plastic compatible
paint to match the grille frame to the vehi-
cle’s interior color.
6
Figure A
METAL GRILLE
GRILLE FRAME
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Wiring
Use 2-conductor stranded type,
insulated wire to connect the 600GTi
Woofer/Midbass and Tweeter to the
included crossover, and the crossover to
the amplifier as shown in Figure B. A
minimum wire gauge of 18AWG is
recommended, with larger size suggested
for wire runs longer than 10 feet.
The polarity (the positive / negative
orientation of the connections) for every
speaker and crossover to amplifier
connection must be consistent from left to
right channel to assure proper imaging and
optimum frequency response. This does
not mean that the 600GTi should always
be connected in the same polarity as the
other drivers in the system however. It is
possible, that due to the difference in the
distance the sound travels from the
woofer/midbass to your ears compared to
the distance from the woofer/midrange or
subwoofer in a typical system, and the
short wavelengths of sound at the
crossover frequency, that a connection
where the midranges or subwoofers are
connected in reverse polarity from the
600GTi Drivers may actually result in
better sound. Because there is no way to
accurately predict this before installation,
we recommend that you try the connection
both ways, and leave it in the polarity that
gives the smoothest audible transition
between the woofer/midbass, subwoofer
and/or midrange. When the subwoofer,
midrange, and midbass drivers are
mounted close to each other, the in-phase
connection will usually yield the best
sound. Active crossovers such as the JBL
GTX47 sometimes include a phase switch
that lets you easily try both polarities by
merely flipping the switch polarity.
System Connections
There are a variety of system options
available with the 600GTi. The simplest
configuration is to use the 600GTi low
passed. In this situation, the 600GTi is
used as a small subwoofer. In small
vehicles at moderate power levels this will
yield good sound. You may also wish to
use the 600GTi in multiples, for example
four 600GTi Drivers will move nearly the
same air volume as a pair of 10" drivers.
This is a good solution when you have a
narrow area that won’t fit larger diameter
subwoofers. The best performance will be
achieved in a high-end 4-way system
which includes subwoofers and additional
midrange and high frequency transducers.
Here the 600GTi is at its best, adding
impact and power to the midbass
7
AMPLIFIER
AMPLIFIER
HEAD
UNIT
ACTIVE
X-OVER
AMPLIFIER
HEAD
UNIT
PASSIVE
X-OVER AMPLIFIER
AMPLIFIER
tweeter
JBL 08GTi
tweeter
JBL 08GTi
midrange
JBL 400GTi
midrange
JBL 400GTi
midbass
JBL 600GTi
midbass
JBL 600GTi
woofer
JBL 1200GTi
woofer
JBL 1200GTi
Figure B
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frequencies. Because the 600GTi are
specifically designed for midbass
frequency operation, in a 4-way system as
described they should have their low and
high frequencies blocked by an active or
passive bandpass crossover in order to
achieve the best system fidelity and the
widest dynamic range.
For the best performance, we
recommend that an active crossover with
a minimum of 12dB per octave slope be
used for the transition point between the
Subwoofer and the 600GTi. The optimum
crossover frequency for this transition is
dependent on the specific components
used, the vehicle, and other installation
details. As a general rule, the crossover
frequency should be as low as possible
to achieve the best system imaging. You
can fine-tune the crossover after the
installation is complete for the best sound.
A good place to start your tuning process
is approximately 50Hz for the subwoofer
to midbass high-pass crossover point.
Higher crossover frequencies will allow the
speaker to play louder. Since no crossover
is perfect, it is advisable to keep your
crossover points away from the range
where your hearing is most sensitive.
Therefore we recommend that you try to
keep the low-pass frequency below
250Hz. This lets your full-range system
reproduce the frequencies covering the
most important vocal and lead instrument
fundamentals and their harmonics, which
will help optimize imaging.
If you prefer to use all passive
crossovers, you will need to construct or
purchase a band-pass filter for the desired
midbass frequency range and install it in-
line ahead of the 600GTi. Although the
wide range and smooth roll-off of the
600GTi allows the use of a simple 6dB per
octave filter, for the best system dynamic
range, we recommend that a minimum
slope of 12dB per octave be used.
The most advanced system designs
use active electronic crossovers such as
the JBL GTX2, GTX4 or GTX47 at both the
subwoofer to midbass transition point and
at the midbass-to-midrange transition. The
maximum recommended RMS amplifier
power routed directly to the 600GTi
is 300 watts.
Speaker Break-In
The 600GTi Woofer/Midbass uses
many high strength materials which benefit
from a break-in period to achieve top per-
formance. The 600GTi will reach maximum
performance after playing for about one
hour at a moderate volume level.
A Note on Power Handling
As a result of their high efficiency,
all JBL loudspeakers will produce reason-
able volume levels in the automotive
environment using very little amplifier
power. However, the use of a low-powered
amplifier to attain very high volume levels
could lead to overdriving the amplifier. This
will generate high distortion levels which
can easily damage loudspeakers,
even if
the rated power of the amplifier is below
the rated maximum power handling of the
loudspeaker!
As a general rule, do not turn up the
volume control past the point where you
hear distortion in the form of either signal
distortion from an overdriven amplifier or
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mechanical noise from an overstressed
speaker.
For the best performance and
system reliability, you should select an
amplifier with an output rating greater than
the maximum power likely to be used to
generate the desired volume levels.
If you
want your system “Loud + Clear,” we
suggest that you step up to a JBL power
amplifier which has an RMS power rating
equal to, but not exceeding, the
Maximum
Recommended Amplifier Power
listed in
the specifications of your specific JBL
speaker. This margin of reserve power will
ensure that the amplifier will not attempt to
deliver more power than its design allows.
Your dealer will be happy to point out
which high-power JBL amplifiers are
optimum for your application and listening
habits.
Following these guidelines will provide
virtually distortion-free sound reproduction
and long loudspeaker life.
In Case of Difficulty
The most common difficulties are
noise, distortion, and intermittent
connections.
System noise is usually not the fault of
the 600GTi. Hiss or "alternator whine" is
most often the result of faulty grounding of
the system electronics or improper setting
of amplifier level controls. An exception to
this is if the passive crossover networks
are mounted near a source of radiated
noise, the network may pick-up this noise
with sufficient power to drive the 600GTi.
For this reason, be careful not to mount
any passive crossovers near wires
carrying high currents such as battery
cables or wires leading to ammeters or
tachometers.
Distortion is usually the result of
overdriving one or more components in
the system. The problem is most likely
insufficient amplifier power, or improper
setting of gain controls. Refer to the
instructions which came with the
electronics for assistance. The 600GTi will
not play as loudly, or handle the full rated
power, when used without a subwoofer
and associated high-pass crossover.
When using the 600GTi without a high-
pass filter, be careful to limit the volume
level to that which can be reproduced
without audible distortion from the speaker.
If you want to talk to us about any
problems, call JBL Customer Service at
1-800-336-4JBL (4525) between 9AM and
5PM eastern time.
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Specifications: 600GTi
Frequency Response: 45Hz – 3.5kHz
Recommended Minimum High-Pass Crossover Frequency
for High Power Operation: 50Hz
Continuous Power Handling With 12dB Passive Network
High Passed at Recommended Minimum Frequency: 300 Watts
Continuous Power Handling When Used Without
High-Pass (Subwoofer Operation): 75 Watts
Minimum Recommended Amplifier Power: 20 Watts
Maximum Recommended Amplifier Power Rating: 300 Watts
Sensitivity (2.83 Volts / 1 Meter): 90dB
Impedance: 4 Ohms
Dimensions – Woofer/Midbass Transducers:
Overall Maximum Diameter
(Mounting Tab to Mounting Tab): 71/2" (191mm)
Height: 3 7/32" (81mm)
Mounting Depth: 27/8" (73mm)
Cutout Size: 57/8" (149mm)
Weight: 4 lbs. 9 oz. (2.1kg)
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Thiele-Small Specifications: 600GTi
Free Air Resonance (Fs): 56Hz
Electrical Damping (Qes): 0.60
Mechanical Damping (Qms): 6.40
Total Damping (Qt): 0.55
Equivalent Volume of Compliance (Vas): 0.455 cu. ft. (12.9 liters)
Effective ConeArea (Sd): 21.7 sq. inches (0.014 m2)
Center to Peak Linear Excursion (Xmax): 0.250 in (6.35mm)
Voice Coil DC Resistance (Re): 3.5 ohms
Voice Coil Inductance (Le): 0.24mH @ 1kHz
Voice Coil Diameter: 2 inches (50.8mm)
Voice Coil Length (Winding Length): 0.650 inches (16.5mm)
Air Gap Height: 0.250 inches (6.35mm)
BL Product: 6.4 T/M
Effective Moving Mass (Mm): 0.606 ounces (17.2 grams)
Note: The Thiele-Small specifications shown apply only after a break-in period of approximately 2 hours.
JBL continually strives to improve its products. New materials, production methods and other refinements may result in a change from
published specifications and description. The changes will equal or exceed the original specifications, unless otherwise stated.
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A Harman International Company
NMGP/N:304595-001 5/94
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