Rockford Fosgate 1000, 360, 400 User Manual

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car audio

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Power AMPLIFIER

INSTALLATION & OPERATION

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®

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POWER 360 POWER 400 POWER 500 POWER 800 POWER 800 POWER 1000

2-channel 4-channel 2-channel 2-channel 4-channel 2-channel

481 Watts x 1 232 Watts x 2 710 Watts x 1 960 Watts x 1 525 Watts x 2 1460 Watts x 1

242 Watts x 2 127 Watts x 4 330 Watts x 2 480 Watts x 2 270 Watts x 4 730 Watts x 2

154 Watts x 2 84 Watts x 4 210 Watts x 2 240 Watts x 2 150 Watts x 4 450 Watts x 2

90 Watts x 2 50 Watts x 4 125 Watts x 2 200 Watts x 2 100 Watts x 4 250 Watts x 2

180 Watts x 2 100 Watts x 4 250 Watts x 2 400 Watts x 2 200 Watts x 4 500 Watts x 2

360 Watts x 1 200 Watts x 2 500 Watts x 1 800 Watts x 1 400 Watts x 2 1000 Watts x 1

50Hz – 210Hz 50Hz – 210Hz 50Hz – 210Hz 50Hz – 210Hz 50Hz – 210Hz 50Hz – 210Hz

PECIFICATIONS

S

Dynamic Power Rating

(IHF-202 Standard) - Measured at 14.4 Volts

Mono into a 4Ω Load

Per channel into a 2Ω Load

Per channel into a 4Ω Load

Continuous Power Rating

(Competition Standard) - Measured at 13.8 Battery Volts

RMS continuous power per channel,

both channels driven into a 4Ω load

from 20 to 20,000 Hz with less than

0.05% Total Harmonic Distortion (THD)

RMS continuous power per channel,

– i –

both channels driven into a 2Ω load

from 20 to 20,000 Hz, with less than

0.1% Total Harmonic Distortion (THD)

RMS continuous power mono into a

4Ω load from 20 to 20,000 Hz, with

less than 0.1% Total Harmonic Distortion (THD)

Signal-to-Noise Ratio (A-weighted) >100dB >100dB >100dB >100dB >100dB >100dB

Crossover Slope (Butterworth) 24dB/octave 24dB/octave 24dB/octave 24dB/octave 24dB/octave 24dB/octave

Crossover Frequency

Specifications are subject to change without notice.

18.27" (46.40cm) L

9.60" (24.38cm) W 9.60" (24.38cm) W 9.60" (24.38cm) W 9.60" (24.38cm) W

9.60" (24.38cm) W

POWER 360 POWER 400 POWER 500 POWER 800 POWER 800 POWER 1000

2-channel 4-channel 2-channel 2-channel 4-channel 2-channel

2.62" (6.65cm) H 2.62" (6.65cm) H 2.62" (6.65cm) H 2.62" (6.65cm) H 2.62" (6.65cm) H 2.62" (6.65cm) H

9.60" (24.38cm) W

12.27" (31.16cm) L 13.27" (33.70cm) L 13.27" (33.70cm) L 18.27" (46.40cm) L 18.27" (46.40cm) L

- 200kHz 20Hz - 200kHz 20Hz - 200kHz

4V (RCA) 250mV~4V (RCA) 250mV~4V (RCA)

17V max. (RCA) 17V max. (RCA) 17V max. (RCA) 17V max. (RCA) 17V max. (RCA) 17V max. (RCA)

overload. Thermal switch shuts down the amplifier in case of overheating.

(0 to +18dB) (0 to +18dB) (0 to +18dB) (0 to +18dB) (0 to +18dB) (0 to +18dB)

Specifications are subject to change without notice.

Dimensions (end caps installed)

Heatsink Type (internal use only) #3 #4 #4 #6 #6 #6

Frequency Response (±0.5dB) 20Hz - 20kHz 20Hz - 20kHz 20Hz - 20kHz 20Hz - 20kHz 20Hz - 20kHz 20Hz - 20kHz

Bandwidth (±3dB) 20Hz - 200kHz 20Hz - 200kHz 20Hz - 200kHz 20Hz

Damping Factor @ 4Ω (at output connector) >200 >200 >200 >200 >200 >200

Slew Rate 30 Volts/ µs 30 Volts/ µs 30 Volts/ µs 30 Volts/ µs 30 Volts/ µs 30 Volts/ µs

IM Distortion (IHF) <0.05% <0.05% <0.05% <0.05% <0.05% <0.05%

Input Sensitivity (+0dB gain overlap) 250mV~4V (RCA) 250mV~4V (RCA) 250mV~4V (RCA) 250mV~

Source Unit Compatibility (+15dB gain overlap)

– ii –

Protection NOMAD - Internal analog-computer output protection circuitry limits power in case of

Battery Fuse Rating (External to Amplifier) 40A 50A 50A 60A* 60A* 2-50A or 1-100A*

Fuse Type ATC AGU AGU AGU AGU 2-AGU OR 1- ANL

Equalization (45Hz Punch Bass) Variable Rear Variable Variable Variable Rear Variable Variable

Input Impedance 20k ohms 20k ohms 20k ohms 20k ohms 20k ohms 20k ohms

* recommended fuse not supplied with amplifier

Dear Customer,
Congratulations on your purchase of the world's finest brand of car audio amplifiers.

At Rockford Fosgate we are fanatics about musical reproduction at its best, and we are
pleased you chose our product. Through years of engineering expertise, hand craftsman­ship and critical testing procedures, we have created a wide range of products that
reproduce music with all the clarity and richness you deserve.

For maximum performance we recommend you have your new Rockford Fosgate
product installed by an Authorized Rockford Fosgate Dealer, as we provide specialized
training through Rockford Technical Training Institute (RTTI). Please read your
warranty and retain your receipt and original carton for possible future use.

Great product and competent installations are only a piece of the puzzle when it comes
to your system. Make sure that your installer is using 100% authentic installation
accessories from Connecting Punch in your installation. Connecting Punch has
everything from RCA cables and speaker wire to Power line and battery connectors.
Insist on it! After all, your new system deserves nothing but the best.

To add the finishing touch to your new Rockford Fosgate image order your Rockford
wearables, which include everything from T-shirts and jackets to hats and sunglasses.

To get a free brochure on Rockford Fosgate products and Rockford accessories, in the
U.S. call 480-967-3565 or FAX [phone]. For all other countries, call +001-480­967-3565 or FAX [phone].

PRACTICE SAFE SOUND™

CONTINUOUS EXPOSURE TO SOUND PRESSURE LEVELS OVER 100dB

CAUSE PERMANENT HEARING LOSS. HIGH POWERED AUTOSOUND

MAY
SYSTEMS

MAY PRODUCE SOUND PRESSURE LEVELS WELL OVER

130dB. USE COMMON SENSE AND PRACTICE SAFE SOUND.

If, after reading your manual, you still have questions regarding this product,
we recommend that you see your Rockford Fosgate dealer. If you need further
assistance, you can call us direct at 1-800-669-9899. Be sure to have your serial
number, model number and date of purchase available when you call.

The serial number can be found on the outside of the box. Please record it in
the space provided below as your permanent record. This will serve as
verification of your factory warranty and may become useful in recovering your
amplifier if it is ever stolen.

Serial Number: ________________________________
Model Number:________________________________

– iii –

T

ABLE OF

C

ONTENTS

Specifications.............................................................................................. i

Introduction................................................................................................ 1

Power Amplifier Accessory Pack ................................................................... 1

Feature Chart.............................................................................................. 2

Design Features ..........................................................................................3

Installation Considerations ........................................................................... 7

Mounting Location ......................................................................................8

Battery and Charging .................................................................................. 9

Wiring the System....................................................................................... 9

Using Passive Crossovers........................................................................... 11

Table of Component Values........................................................................ 12

Installation ...............................................................................................13

Operation................................................................................................. 21

System Diagrams...................................................................................... 24

Troubleshooting........................................................................................ 28

Dynamic Power Measurements................................................................... 31

Warranty Information ................................................................................ 33

International Information............................................................................ 34

GETTING STARTED

Welcome to Rockford Fosgate! This manual is designed to provide information
for the owner, salesperson and installer. For those of you who want quick
information on how to install this product, please turn to the

Section

of this manual or refer to the icons listed below. Other information can
be located by using the Table of Contents. We, at Rockford Fosgate, have
worked very hard to make sure all the information in this manual is current. But,
as we are constantly finding new ways to improve our product, this information
is subject to change without notice.

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Sections marked

ADVANCED OPERATION

include in-depth

technical information

Sections marked

INSTALLATION

include “slam dunk”

wiring connections

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include recommendations for

curing installation problems

Installation

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Sections marked

TROUBLESHOOTING

I

NTRODUCTION

Rockford engineers designed the Power amplifiers to provide an awesome
amount of power while delivering superior sound quality in a convenient and
efficient package. The TRANS•
low voltage circuits used in the preamp stage of the Power amplifiers that let
the music sound crystal clear and very real, even when played at high
volume levels. This is matched with TOPAZ, a unique grounding circuit used
to eliminate noise problems associated with car audio systems and their
installation. The use of a protection circuit called NOMAD, along with
MOSFET, DSM (Discrete Surface Mount) and innovative MEHSA heat
dissipating technologies improves amplifier efficiency. The result of these
components give the Power amplifier awesome sound quality in a “Bullet
Proof” package.

P

OWER AMPLIFIER

The accessory pack shipped with the Power amplifiers includes the mounting
hardware necessary to secure the amp to the vehicle.

A

ana

& patented TRANS•

CCESSORY PACK

nova

topologies are

Installation & Operation Manual
Punch Verification Certificate
(4) Amplifier mounting screws (#8 x 3/4" Phillips)
(4) Speaker/Power connector set screws (3/32" Allen)
(4) Endbell mounting screws (9/64" Allen)
(1) Allen wrench (3/32")
(1) Allen wrench (9/64")
(1) Inline fuseholder (Power 360, Power 400 & Power 500 2-channel amps)
(1) AGU 40 amp fuse (Power 360 2-channel amp)
(1) AGU 50 amp fuse (Power 400 4-channel & Power 500 2-channel amps)
(1) Remote Punch Bass (replacement part #WP-2429)
(1) 15' Remote Punch Bass cable (replacement part #CC-2421)
(2) Remote Punch Bass bracket screws (4 x 7/16" Phillips)

NOTE: Refer to the specifications section for recommended fuse sizes on the
Power 800 2-channel, Power 800 4-channel & Power 1000 2-channel amps.

– 1 –

P

OWER AMPLIFIER FEATURE CHART

POWER AMPLIFIER MODEL Power Power Power Power Power Power

360 400 500 800 800 1000

# of CHANNELS 2422 42

Stable Into: (stereo/mono) 2Ω/4Ω 2Ω/4Ω 2Ω/4Ω 2Ω/4Ω 2Ω/4Ω 2Ω/4Ω

CIRCUITRY

TRANS•
TRANS•
DIAMOND

1

ana

– circuit topology xxxx x–

nova

– patented circuit topology

– patented MOSFET driver stage

2

–––– –x

3

–––– –x
Class-G – high efficiency topology –––– ––
MEHSA – heat dissipating technology xxxx xx
TOPAZ

– patented noise eliminating circuitry

4

xxxx xx
DSM – discrete surface mount xxxx xx
MOSFETs – power supply & output devices xxxx xx
NOMAD – protection circuit xxxx xx

FEATURES

Die Cast Heatsink

5

xxxx xx
Hi-Level Inputs – for factory radios –––– ––
RCA Inputs – for aftermarket radios xxxx xx
Input Switches – eliminates “Y” adaptors –x–– x–
Pass-Thru – feeds signal to aux. amp xxxx xx
Pwr/Spk Screw Terminals –––– ––
Pwr/Spk Block Terminals xxxx xx
4 Gauge PWR/GND xxxx xx
Variable Punch Bass (0dB ~+18dB @ 45Hz) Remote Remote Rear Remote Remote Remote Rear Remote
Variable Xover (50Hz ~ 210Hz) HP/FULL/LP

6

HP/FULL/LP6HP/FULL/LP6 HP/FULL/LP

6

HP/FULL/LP

6

HP/FULL/ LP

6

Crossover Slope (Butterworth) 24dB 24dB 24dB 24dB 24dB 24dB

0

Phase Warp (0

1

Additional information on features, specifications and system designs can be found at: www.rockfordfosgate.com

2

Trans•nova is patented under "U.S. Patent No. 4,467,288"

3

DIAMOND is patented under "U.S. Patent No. 5,673,000"

4

TOPAZ is patented under "U.S. Patent No. 5,751,823"

5

Diecast Heatsink is patented under "U.S. Patent No. D401,225"

6

HP = 24dB/octave High-Pass / LP = 24dB/octave Low-Pass / FULL = Full Range

7

Recommended fuses not supplied with amplifier

0

~ 180

) –––– –x

– 2 –

D

ESIGN FEATURES

Power 360

2-channel

Power 400

4-channel

Speaker

9

+ L -

2

9

Hz

210

50

190

55

145

110

65

80

Crossover Frequency

Left Gain

LR

Pass-Thru

LR

77

5

Input

8

Right

Remote

Gain

Punch Bass

HP-Full-LP
Crossover

2

9

Speaker

+ R -

1

6

3

10

LED

REM

9

7

4

2

B+ GND

5

9

9

7

8

1

Front
Crossover
HP-Full-LP

Hz

210

50

190

55

145

4/2

110

Input

Front
Gain

Crossover
Frequency

65

80

Front

Front Pass-Thru Rear

RR

LL

210
190
145

110

Rear

Crossover

Frequency

Hz

50

55

65

80

Rear
Gain

6

2

3

LR+ LR- RR+ RR- B+ GND LF- LF+ RF+RF-

REM

2

10

LED

– 3 –

Rear
Crossover
HP-Full-LP

2

Rear

Remote

Punch

Bass

Power 500

2-channel

Power 800

2-channel

Speaker
+ L -

8 99

7

5

Input

Right

Remote

Gain

Punch Bass

HP-Full-LP
Crossover

Speaker
+ R -

2

Hz

210

50

190
145

110

65

80

Crossover Frequency

55

Left Gain

7

LR

LR

Pass-Thru

2

1

6

3

10

LED

REM

2

9

2

B+ GND

5

77

8

2

9

1

Speaker
+ L -

Hz

210

50

190

55

145

110

65

80

Crossover Frequency

3

10

LED

REM

Left Gain

Input

LR

Pass-Thru

LR

6

2

B+ GND

– 4 –

HP-Full-LP
Crossover

Right

Remote

Gain

Punch Bass

Speaker
+ R -

Power 800

4-channel

5

9 9

899 774

1

Power 1000

2-channel

Front
Crossover
HP-Full-LP

Hz

210

50

190

55

145

4/2

110

Input

Front
Gain

Crossover
Frequency

65

80

Front

Front Pass-Thru Rear

RR

LL

210

190

145

110

Crossover
Frequency

Hz

50

55

65

80

Rear

HP-Full-LP

Rear

Gain

6

3

7

Left

Gain

2

5

Input

LR

Pass-Thru

LR

10

LED

8 99

7

HP–Full–LP
Crossover

Right

Remote

Gain

Punch Bass

2 2

REM

LR+ LR- RR+ RR- B+ GND LF- LF+ RF+RF-

2

11

Crossover

Phase

Frequency

Warp

Hz

210

50

190

55

Speaker
+ L -

145

110

65

80

6

10

3

2

Rear

Crossover

Speaker
+ R -

Rear
Remote
Punch

Bass

2

1

LED

REM

B+ GND

– 5 –

1. Cast Aluminum Heatsink – The cast aluminum heatsink of the Power
amplifier dissipates heat generated by the amplifier's circuitry. The inherent
advantage of casting provides a 30% improvement of cooling over conven­tional extrusion heatsink designs.

2. Speaker/Power Terminals – The heavy duty, gold-plated terminal block
connectors (+ and –) will accept 4 gauge cable and are immune to corrosion
that can cause signal degradation.

3. REM Terminal – This spade terminal is used to remotely turn on and turn off
the amplifier when +12V DC is applied.

4. Signal Input Switch (Power 400 & Power 800 4-channel amplifiers) – This
switch allows the amplifier to be driven with either 2 or 4 pairs of inputs.

5. RCA Input Jacks – The industry standard RCA jacks provide an easy
connection for signal level input. They are gold-plated to resist the signal
degradation caused by corrosion.

6. RCA Pass-Thru Jacks – The Pass-Thru provides a convenient source for
daisy-chaining an additional amplifier without running an extra set of RCA
cables from the front of the vehicle to the rear amplifier location.

7. Gain Control – The input gain control is preset to match the output of most
source units. It can be adjusted to match output levels from a variety of source
units.

8. Remote Punch Bass – The Punch Bass helps correct for acoustical
deficiencies in the listening environment by helping reproduce full range
sound without adding excessive boost. The Punch Bass control is a narrow
band adjustment centered at 45Hz variable from 0dB to +18dB. Connection
is made with a cable using RJ-45 and can be installed under the dash for
remote control access.

9. Internal Crossover – The internal crossover is a 24dB/octave Butterworth
filter selectable for High-Pass (HP), Full Range (FULL), or Low-Pass (LP)
operation variable from 50Hz to 210Hz.

10. LED Power Indicator – The LED illuminates when the unit is turned on.

11. Phase Warp (Power 1000 2-channel amplifier) – The phase warp is a

variable control used to adjust the phase of the output signal relative to the
phase of the input signal. The phase warp is most noticable when the system
is playing a sine wave (test tone). When used with the proper test equipment,
this feature can increase the relative SPL in a system.

– 6 –

I

NSTALLATION

The following is a list of tools you will need for installing the Power amplifier:
Voltmeter Wire strippers
Electric hand drill w/assorted bits Battery post wrench
17' (5 m) Red Power Wire Wire cutters
12' (4 m) Remote Turn-On Wire Assorted connectors

1.5' (45 cm) Black Grounding Wire Wire crimpers
This section focuses on some of the vehicle considerations for installing your

new Power amplifier. Checking your battery and present sound system, as
well as pre-planning your system layout and best wiring routes, will save
installation time. When deciding how to lay out your new system, be sure that
each component will be easily accessible for making adjustments.

Before beginning any installation, be sure to follow these simple rules:

1. Be sure to carefully read and understand the instructions before attempt-

ing to install the amplifier.

2. For safety, disconnect the negative lead from the battery prior to

beginning the installation.

3. For easier assembly, we suggest you run all wires prior to mounting your

amplifier in place.

4. Route all of the RCA cables close together and away from any high

current wires.

5. Use high quality connectors for a reliable installation and to minimize

signal or power loss.

6. Think before you drill! Be careful not to cut or drill into gas tanks, fuel

lines, brake or hydraulic lines, vacuum lines or electrical wiring when
working on any vehicle.

7. Never run wires underneath the vehicle. Running the wires inside the

vehicle provides the best protection.

8. Avoid running wires over or through sharp edges. Use rubber or plastic

grommets to protect any wires routed through metal, especially the
firewall.

9. ALWAYS protect the battery and electrical system from damage with

proper fusing. Install a fuseholder and appropriate fuse on the +12V
power wire within 18” (45 cm) of the battery terminal.

10. When grounding to the chassis of the vehicle, scrape all paint from the

metal to ensure a good, clean ground connection. Grounding connec­tions should be as short as possible and always be connected to metal
that is welded to the main body, or chassis, of the vehicle.

C

ONSIDERATIONS

– 7 –

M

OUNTING LOCATION

The mounting location and position of your amplifier will have a great effect
on its ability to dissipate the heat generated during normal operation. The
design of our cast aluminum heatsink serves to easily dissipate the heat
generated over a wide range of operating conditions. However, to maximize
the performance of your amplifier, care should be taken to ensure adequate
ventilation.

Trunk Mounting

Mounting the amplifier vertically on a surface with the fin grooves running
up and down will provide the best cooling of the amplifier.

Mounting the amplifier on the floor of the trunk will work but provides less
cooling capability than vertical mounting.

Mounting the amplifier upside down to the rear deck of the trunk will not
provide proper cooling and will severely affect the performance of the
amplifier and is strongly

Passenger Compartment Mounting

Mounting the amplifier in the passenger compartment will work as long as
you provide a sufficient amount of air for the amplifier to cool itself. If you
are going to mount the amplifier under the seat of the vehicle, you must have
at least 1" (2.54cm) of air gap around the amplifier's heatsink.

not

recommended.

Mounting the amplifier with less than 1" (2.54cm) of air gap around the
amplifier's heatsink in the passenger compartment will not provide proper
cooling and will severely affect the performance of the amplifier and is
strongly

not

recommended.

Engine Compartment Mounting

Rockford Fosgate amplifiers should
compartment. Not only will this void your warranty but could create an
embarrassing situation caused by the ridicule from your friends.

– 8 –

never

be mounted in the engine

B

ATTERY AND

C

HARGING

Amplifiers will put an increased load on the vehicle's battery and charging
system. We recommend checking your alternator and battery condition to
ensure that the electrical system has enough capacity to handle the
increased load of your stereo system. Stock electrical systems which are in
good condition should be able to handle the extra load of any Rockford
amplifier without problems, although battery and alternator life can be
reduced slightly. To maximize the performance of your Rockford Fosgate
amplifier, we suggest the use of a heavy duty battery and an energy storage
capacitor.

W

IRING THE SYSTEM

CAUTION: Avoid running power wires near the low level input cables,
antenna, power leads, sensitive equipment or harnesses. The power wires
carry substantial current and could induce noise into the audio system.

1. Plan the wire routing. Take care when running signal level RCA cables
to keep them close together but isolated from the amplifier's power
cables and any high power auto accessories, especially electric
motors. This is done to prevent coupling the noise from radiated
electrical fields into the audio signal. When feeding the wires through
the firewall or any metal barrier, protect them with plastic or rubber
grommets to prevent short circuits. Leave the wires long at this point
to adjust for a precise fit at a later time.

2. Prepare the Power cable for attach­ment to the amplifier by stripping
5/8" of insulation from the end of
the wire. The use of 8 gauge power
cable can interfere with the installa-

STRIP WIRE

AMP

>

5/8"

>

INSULATION

>

><

tion of the end caps. Proper wire
dress can prevent this from occur­ring. To prevent the wire from fray­ing, strip the insulation at a 45°
angle. Insert the bared wire into the B+ terminal with the long side of
the insulation on the top. Bend the cable down at a 90° angle. Tighten
the set screw to secure the cable in place.

3. Strip 3/8" from the battery end of the power cable and crimp a large
ring terminal to the cable. Use the ring terminal to connect to the
battery positive terminal. Do not install the fuse at this time.

– 9 –

4. Prepare a length of cable to be used for the ground connection. Strip
5/8" of insulation from the end of the cable as described above and
connect to the appropriate terminal of the amplifier. Prepare the chassis
ground by scraping any paint from the metal surface and thoroughly
clean the area of all dirt and grease. Strip the other end of the wire and
attach a ring connector. Fasten the cable to the chassis using a non­anodized screw and a star washer.

5. Prepare the REM turn-on wire for connection to the amplifier by stripping
1/4" of insulation from the wire end and crimping an insulated spade
connector in place. Slide the connector over the REM terminal on the
amplifier. Connect the other end of the REM wire to a switched 12 volt
positive source. The switched signal is usually taken from the source
unit's auto antenna or the accessory lead. If the source unit does not
have these outputs available, the recommended solution is to wire a
mechanical switch in line with a 12 volt source to activate the amplifier.

6. Securely mount the amplifier (with supplied screws) to the vehicle or
amp rack. Be careful not to mount the amplifier on cardboard or plastic
panels. Doing so may enable the screws to pull out from the panel due
to road vibrations or sudden vehicle stops.

7. Determine the number of inputs needed to drive the amplifier and move
the input switch to the desired setting (Power 400 & Power 800 4­channel amplifiers only.).

8. Connect the source signal to the amplifier by plugging the RCA cables
into the input jack(s) at the amplifier.

9. Connect the speakers. Strip the speaker wires 5/8" and insert into the
appropriate terminal on the amplifier. Insert the bared wire into the
speaker terminal and tighten the set screw to secure into place. Be sure
to maintain proper speaker polarity.

DO NOT chassis ground any of the

speaker leads as unstable operation may result.

10. Perform a final check of the completed system wiring to ensure that all
connections are accurate. Check all power and ground connections for
frayed wires and loose connections which could cause problems from
road vibrations.

– 10 –

U

SING PASSIVE CROSSOVERS

A passive crossover is a circuit that uses capacitors and/or coils and is placed
on speaker leads between the amplifier and speaker. The crossover delegates
a specific range of frequencies to the speaker for optimum driver performance.
A crossover network can perform one of three functions: High-Pass (capaci­tors), Low-Pass (inductors or coils) and Bandpass (combination of capacitor
and coil).

The most commonly used passive crossover networks are 6dB/octave
systems. These are easy to construct and require one component per filter.
Placing this filter in series with the circuit will reduce power to the speaker by
6dB/octave above or below the crossover point depending on whether it is a
high-pass or low-pass filter. More complex systems such as 12dB/octave or
18dB/octave can cause impedance problems if not professionally designed.

Passive crossovers are directly dependent upon the speaker's impedance and
component value for accuracy. When passive crossover components are
used in multiple speaker systems, the crossover's effect on the overall
impedance should be taken into consideration along with the speaker's
impedance when determining amplifier loads.

fiers are not recommended for impedance loads below 2Ω stereo and 4Ω
bridged (mono) loads.

+

CAUTION: The Power ampli-

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