P 7520 (serv.man3) - JBL Car Audio User Guide / Operation Manual

2

• 4, 3 or 2 channel Operation (P-7540),  

2 or One channel Operation (P-7520),
Mono Class-D subwoofer channel 
(P-2510)

• Simultaneous stereo and mono

Operation (P-7520, P-7540)

• Built-in 12dB/oct variable electronic

crossover

• Balanced Differential Input 
• Front and Rear Summing Inputs (P-2510)

for Non-fading  Bass

• Pre-amp outputs with crossover (P-7520,

P-7540)

• Oversized Floating Rail Mosfet Power

Supply

• Universal Interface
• Common Sense Turn-on
• Variable Input Sensitivity (250mV-4V)
• Fully Complementary, Direct Coupled

Discrete Power Amplifier Circuitry

• Ultra-efficient Class-D Subwoofer

Amplifier (P-2510)

• Gold-Plated Power, Input and Output

Connectors

• 2-Ohm Stable (stereo)
• JBL badge lights when amp is

operating, and flashes when protection
circuit is activated

• Made in USA

To attain maximum amplifier
performance, we encourage you to read
the remaining pages before installing and
operating your new JBL Power Series
Amplifier. Especially review the
Applications section for ideas on
designing and expanding your system.
Also, save these instructions for future
reference. 
IMPORTANT: Installation of automotive
stereo components can require extensive
experience in performing a variety of
electrical and mechanical procedures.
Although these instructions explain how
to install a JBL Power Series Amplifier in
a general sense, they do not show the
exact installation methods for your
particular vehicle. If you do not have the
experience, do not attempt the
installation yourself; instead ask your
Authorized JBL Car Audio Dealer about
professional installation options.

• The JBL Power Series amplifiers have

five levels of circuit protection that
monitor the amplifiers and will shut
them down if the electrical system
voltage drops below 5 Vdc or exceeds
18 Vdc, temperatures are above 194° F
(90° C), short circuits occur, or current
draw exceeds product specifications. For
best performance, check the intended
mounting site to make sure the
operating environment does not create
conditions that will trigger circuit
protection.

• Prior to installation, turn off all audio

systems and other electrical devices.
Also disconnect the (–) negative lead
from the vehicle’s battery.

• At the installation site, locate and make

a note of all fuel lines, hydraulic brake
lines, and electrical wiring. Use extreme
caution when cutting or drilling in and
around these areas.

• Check clearances on both sides of a

planned mounting surface before
drilling any holes or installing any
screws. Remember that mounting
screws can extend behind the mounting
surface. 

for purchasing your new JBL

Power Series Amplifier. Power Series
amplifiers feature the latest advances in
discrete circuit topology ensuring low
distortion and superbly clean and clear
sound quality.  In addition to RCA type
pre-amp inputs,  Power Series amplifiers
feature  Universal Interface™, designed to
facilitate integration with factory installed
audio systems for distortion free
performance that rivals conventional pre-
amp connections. Included in the
Universal Interface circuit is Common
Sense™ turn-on. Common Sense turn-on
senses the common-mode voltage
present on the speaker outputs of factory
and aftermarket radios, turning on the
amplifier without a separate remote wire.
All Power Series amplifiers feature built-
in electronic crossovers and pre-amp
outputs for easy system expansion
without requiring outboard processors.

3

• Always wear protective eyewear when

using tools. 

• When routing cables, keep input signal

cables away from power cables and
speaker wires. 

• When making connections, make sure

that each connection is clean, insulated,
and properly secured. Observe the
polarity markings on the rear panel.
Refer to the application drawings to set
up the amplifier for operation in stereo,
bridged-mono, bi-amp, or tri-mode
configurations.

• If the amplifier’s fuse must be replaced,

use only the same rating and type as a
replacement. Do not substitute another
kind.

1. Pre-amp Level Input Connector–

Connects to line level output from the
source unit. 

2. Universal Interface Speaker Level

Connector-Connects to speaker level
output from the source unit. Provides
Common Sense amplifier turn-on
when used with factory radios. 
(2-channel on P-7520, 4-channel on 
P-7540)

3. Pre-amp Level Output Connector-

connects to other amps or processors
in the signal chain  (flat on P-7520, flat
or filtered on P-7540)

4. Speaker Output Connector - (2-channel

on P-7520, 4-channel on P-7540)

5. Fuses-P-7520: 30A ATC type  P-7540:

30A ATC type x 2, P-2510: 40A ATC type.

6. Power Connector-Connections for 

12V +, Gnd. and Rem.

7. Input Mode Switch-Sums left and right

inputs.

8. Input Sensitivity Control-Adjusts input

sensitivity for pre-amp level and
speaker level inputs.

9. Pre-amp  Output Selector Switch-

Selects input path for pre-amp output.
Output can be summed from front and
rear inputs with no filter, or filtered by
the front or rear crossover.

10. Rear Channel Input Selector-Selects

rear channel input between front input
and rear input.

11. Crossover Selector-Determines

whether the crossover is a High Pass
filter (HP), Low Pass filter (LP), or
unfiltered (flat).

12. Crossover Frequency Control-

Determines the crossover frequency
for the amplifier channels (front or
rear) and the pre-amp outputs.

30

30

7540

30

3. If you are running either the P-7520 or

the P-7540  in Tri-Mode (stereo and
mono simultaneously to one or two
pairs of satellite speakers and a
subwoofer), refer to the  chart above
to determine the capacitor and
inductor values you’ll need to route
bass signals to the woofer, and
midrange and high frequencies to the
satellite speakers. These passive
crossover components will also ensure
that the impedance of the speaker
system doesn’t drop below 2 Ohms.
The P-2510 should be used to drive
woofers only as its bandwidth is
limited to 20Hz - 320Hz.

1. If you are using conventional RCA

input connections and a source unit
with output voltage less than 4V,
simply plug the RCA plugs into the
RCA jacks on the amplifier.

4

The JBL P-7520, P-7540, or P-2510 can be
mounted in virtually any location inside
the vehicle. However, make sure to keep
the amplifier away from heater vents or
ducts.
1. At the chosen site, use the amplifier as

a mounting template and mark
locations of the four mounting holes.

2. Drill a small pilot hole at each marked

location.

3. Mount the amplifier and securely

tighten the mounting screws.

1. Connect the speakers, observing

proper polarity, to the speaker output
barrier strip on the amplifier using at
least 1,25 mm

2

high quality speaker

wire. (Note: The total impedance of the
speakers connected to the outputs
when the amp is driven in stereo must
be at least 2 Ohms. Because the 
P-2510 is a single channel amplifier,
the speaker connections on the barrier
strip are wired in parallel inside the
amp. The total impedance of the
speakers connected to the P-2510 must
be at least 2 Ohms.) 

2. If you are bridging the amplifier,

connect the speaker wires to the
terminals marked “bridge” observing
proper polarity. (Note: The total
impedance of the speaker system to
be connected to the amplifier must be
at least 4 Ohms in bridge mode)

FREQUENCY

INDUCTOR

CAPACITOR

Crossover 

6dB/oct. LP

6dB/oct. HP

(4 ohm)

(4 ohm)

75Hz

8.0mH

530µF

100Hz

6.4mH

400µF

125Hz

5.0mH

318µF

150Hz

4.2mH

265µF

175Hz

3.6mH

227µF

200Hz

3.2mH

198µF

40

Refer to Figures 1-6 for connector
locations. 
1. For power, remote, and speaker wires,

strip 1⁄4" off one end of each jacket to
reveal bare wire for insertion into the
barrier strip connectors.

2. Locate the 3-connection barrier strip

labeled +Batt, Rem and Gnd. Connect
a black wire (at least 2.5 mm

2

) to the

Gnd terminal and connect the other
end to the nearest bare-metal chassis
component. Then, connect a red wire
(at least 2.5 mm

2

) from the vehicle’s

+12-volt battery terminal to the +Batt
terminal on the barrier strip. Finally
connect a blue wire (1,25 mm

2

) to the

Rem terminal on the barrier strip and
connect the other end to the Rem
output of the source unit. If you are
using speaker level inputs and speaker
level outputs from the source,
disregard the previous instruction
regarding the Rem terminal.