Pioneer GM-X574 User Manual

Setting the Unit

Gain Control

Adjusting the gain controls A and B will
help match the output of the car stereo to
the Pioneer amplifier. Normally, set the
gain controls to the “NORMAL” posi­tion. If the output is low, even when the
volume of the car stereo is turned up,
turn these controls clockwise. If there is
distortion when the volume of the car
stereo is turned up, turn these controls
counter-clockwise.

• If you only use one input plug, set the gain
controls for speaker outputs A and B to the
same position.

• When using with an RCA equipped car
stereo (standard output of 500 mV), set to
the NORMAL position. When using with
an RCA equipped Pioneer car stereo with
max. output of 4 V or more, adjust level to
match the car stereo output level.

• If you hear too much noise when using the
speaker input terminals, turn the gain
control counter-clockwise.

Power Indicator

The power indicator lights when the
power is switched on.

LPF (Low-Pass Filter)/HPF (High-Pass Filter) Select Switch

Set the LPF/HPF select switch as follows according to the type of speaker that is connected
to the speaker output connector and the car stereo system:

LPF/HPF Select Audio frequency range Speaker Remarks

Switch to be output Type

LPF (Left) Very Low Frequency range Subwoofer Connect a subwoofer.

OFF (Center) Full range Full range

HPF (Right) Low Frequency range to Full range Use if you want to cut the

High Frequency range very low frequency range

because it is not necessary
for the speakers you are
using.

BFC (Beat Frequency Control) Switch

If you hear a beat while listening to an
AM broadcast with your car stereo,
change the BFC switch using a small
standard tip screwdriver.

Thank you for purchasing this PIONEER
product. Before attempting operation, be
sure to read this manual.

Composition of Manual

This manual applies to the GM-X574 and
GM-X374. However, the illustrations show
the GM-X574.

In case of trouble

When the unit does not operate properly,
contact your dealer or the nearest autho­rized PIONEER Service Station.

WARNING

• Always use the special red battery and ground
wire [RD-223], which is sold separately. Connect
the battery wire directly to the car battery positive
terminal (+) and the ground wire to the car body.

• Do not touch the amplifier with wet hands.
Otherwise you may get an electric shock. Also, do
not touch the amplifier when it is wet.

• For traffic safety and to maintain safe driving
conditions, keep the volume low enough so that
you can still hear normal traffic sound.

• Check the connections of the power supply and
speakers if the fuse of the separately sold battery
wire or the amplifier fuse blows. Detect the cause
and solve the problem, then replace the fuse with
another one of the same size and rating.

• To prevent malfunction of the amplifier and
speakers, the protective circuit will cut the power
supply to the amplifier (sound will stop) when an
abnormal condition occurs. In such a case, switch
the power to the system OFF and check the
connection of the power supply and speakers.
Detect the cause and solve the problem.

• Contact the dealer if you cannot detect the cause.

• To prevent an electric shock or short-circuit

during connection and installation, be sure to
disconnect the negative (–) terminal of the battery
beforehand.

• Confirm that no parts are behind the panel when
drilling a hole for installation of the amplifier. Be
sure to protect all cables and important equipment
such as fuel lines, brake lines and the electrical
wiring from damage.

Before Using This Product

Input Select Switch

For two-channel input, slide this switch
to the left. For four-channel input, slide
this switch to the right.

PIONEER CORPORATION

4-1, MEGURO 1-CHOME, MEGURO-KU, TOKYO 153-8654, JAPAN

PIONEER ELECTRONICS (USA) INC.

P.O. Box 1540, Long Beach, California 90801-1540, U.S.A.
TEL: [phone]

PIONEER EUROPE NV

Haven 1087, Keetberglaan 1, B-9120 Melsele, Belgium
TEL: [phone]

PIONEER ELECTRONICS ASIACENTRE PTE. LTD.

253 Alexandra Road, #04-01, Singapore 159936
TEL: [phone]

PIONEER ELECTRONICS AUSTRALIA PTY. LTD.

178-184 Boundary Road, Braeside, Victoria 3195, Australia
TEL: [phone]

PIONEER ELECTRONICS OF CANADA, INC.

300 Allstate Parkway, Markham, Ontario L3R OP2, Canada
TEL: [phone]

PIONEER ELECTRONICS DE MEXICO, S.A. de C.V.

San Lorenzo 1009 3er. Piso Desp. 302
Col. Del Valle Mexico, D.F. C.P. 03100
TEL: [phone]

Published by Pioneer Corporation.
Copyright © 2002 by Pioneer Corporation.
All rights reserved.

Publicado por Pioneer Corporation.
Copyright © 2002 Pioneer Corporation.
Todos los derechos reservados.

Printed in U.S.A.
Impreso en los EE.UU.

<HRD0224-A> ES<KYMFX/02I00000>

BRIDGEABLE FOUR-CHANNEL
POWER AMPLIFIER

AMPLIFICADOR DE POTENCIA DE
CUATRO CANALES EN PUENTE

Owner’s Manual

GM-X574
GM-X374

Manual del Propietario

Connecting the Unit

CAUTION

• Disconnect the negative (–) terminal of the battery
to avoid the risk of short-circuit and damage to
the unit.

• Secure the wiring with cable clamps or adhesive
tape. To protect the wiring, wrap adhesive tape
around it where they lie against metal parts.

• Do not route wires where they will get hot, for
example where the heater will blow over them. If
the insulation heats up, it may become damaged,
resulting in a short-circuit through the vehicle
body.

• Make sure that wires will not interfere with mov­ing parts of the vehicle, such as the gearshift,
handbrake or seat sliding mechanism.

• Do not shorten any wires. Otherwise the protec­tion circuit may fail to work when it should.

• Never feed power to other equipment by cutting
the insulation of the power supply wire to tap
from the wire. The current capacity of the wire
will be exceeded, causing overheating.

GM-X574

Speaker Channel Speaker Type Power

Four-channel

Subwoofer Nominal input: Min. 55 W

Other than subwoofer Max. input: Min. 100 W

Two-channel

Subwoofer Nominal input: Min. 135 W

Other than subwoofer Max. input: Min. 260 W

Three-channel Subwoofer Nominal input: Min. 55 W

Speaker output A Other than subwoofer Max. input: Min. 100 W

Three-channel Subwoofer Nominal input: Min. 135 W

Speaker output B Other than subwoofer Max. input: Min. 260 W

To prevent damage

• Do not ground the speaker wire directly or con­nect a negative (–) lead wire for several speakers.

• This unit is for vehicles with a 12-volt battery and
negative grounding. Before installing it in a recre­ational vehicle, truck or bus, check the battery
voltage.

• If the car stereo is kept on for a long time while
the engine is at rest or idling, the battery may go
dead. Turn the car stereo off when the engine is at
rest or idling.

• If the system remote control wire of the amplifier
is connected to the power terminal through the
ignition switch (12 V DC), the amplifier will
always be on when the ignition is on— regardless
of whether the car stereo is on or off. Because of
this, the battery could go dead if the engine is at
rest or idling.

• Speakers to be connected to the amplifier should
conform with the standards listed below. If they
do not conform, they may catch fire, emit smoke
or become damaged. The speaker impedance must
be 2 to 8 ohms. But in case of two-channel and
other bridge connections, the speaker impedance
must be 4 to 8 ohms.

• Install and route the separately sold battery wire
as far away as possible from the speaker wires.
Install and route the separately sold battery wire,
ground wire, speaker wires and the amplifier as
far away as possible from the antenna, antenna
cable and tuner.

• Cords for this product and those for other prod­ucts may be different colors even if they have the
same function. When connecting this product to
another product, refer to the supplied Installation
manuals of both products and connect cords that
have the same function.

Connection Diagram

Fuse (30 A)

Grommet RCA input

Special red battery wire [RD-223] (sold separately)
After making all other connections at the amplifier,
connect the battery wire terminal of the amplifier to
the positive (+) terminal of the battery.

Ground wire (black) [RD-223] (sold separately)
Connect to metal body or chassis.

Amplifier with
RCA input jacks

GM-X574: Fuse (25 A)

× 2

GM-X374: Fuse (30 A) × 1

Car stereo with
RCA output jacks

External Output
If only one input plug is used, do not
connect anything to RCA input jack B.

Connecting wires with RCA pin
plugs (sold separately).

RCA input jack B

RCA output jack

Speaker output terminal
See the “Connecting the
Speaker wires” section
for speaker connection
instructions.

System remote control wire (sold separately)
Connect the male terminal of this wire to the system remote control
terminal of the car stereo (SYSTEM REMOTE CONTROL). The female
terminal can be connected to the auto-antenna relay control terminal. If the
car stereo does not have a system remote control terminal, connect the
male terminal to the power terminal through the ignition switch.

Fuse (30 A)

Front side

Connecting wires with RCA pin
plugs (sold separately).

RCA input jack A

Back side

Speaker input terminal
See the “Using the Speaker Input”
section.

GM-X374

Speaker Channel Speaker Type Power

Four-channel

Subwoofer Nominal input: Min. 40 W

Other than subwoofer Max. input: Min. 70 W

Two-channel

Subwoofer Nominal input: Min. 100 W

Other than subwoofer Max. input: Min. 200 W

Three-channel Subwoofer Nominal input: Min. 40 W

Speaker output A Other than subwoofer Max. input: Min. 70 W

Three-channel Subwoofer Nominal input: Min. 100 W

Speaker output B Other than subwoofer Max. input: Min. 200 W

Connecting the Unit

Connecting the Speaker wires

The speaker output mode can be four-channel, three-channel (stereo +
mono) or two-channel (stereo, mono). Connect the speaker leads to suit the
mode according to the figures shown below.

• When either the RCA input or the speaker input is connected, RCA output
becomes functional. Do not connect both the RCA input and the speaker input at
the same time.

Four-channel mode

Three-channel mode

+

+

≠

+

≠

≠

+

+

≠

+

+

≠

≠

≠

Two-channel mode (stereo)

Two-channel mode (mono)

+

+

≠

≠

+

+

≠

≠

Input Select Switch
For two-channel input, slide this switch to
the left. For four-channel input, slide this
switch to the right.

(Left)
Speaker out A
(Right)

Speaker input
terminal A

Speaker output
terminal

(Right)
Speaker out B
(Left)

Speaker input
terminal B

Speaker input
connector

Input Select Switch
For two-channel input, slide this switch to
the left. For four-channel input, slide this
switch to the right.

(Left)
Speaker out A
(Right)

Speaker input
terminal A

Speaker output
terminal

Speaker out B
(Mono)

Speaker input
terminal B

Speaker input
connector

Speaker (Left)

Speaker (Right)

Input Select Switch
Slide this switch to the left.

Speaker input
terminal A

Speaker output
terminal

Speaker input
connector

Speaker (Mono)

Speaker (Mono)

Input Select Switch
Slide this switch to the left.

Speaker input
terminal A

Speaker output
terminal

Speaker input
connector

Connecting the Power Terminal

• Always use the special red battery and ground
wire [RD-223], which is sold separately. Connect
the battery wire directly to the car battery positive
terminal (+) and the ground wire to the car body.

1. Pass the battery wire from the

engine compartment to the interior
of the vehicle.

• After making all other connections to the
amplifier, connect the battery wire terminal of
the amplifier to the positive (+) terminal of
the battery.

2. Twist the battery wire, ground wire
and system remote control wire.

3. Attach lugs to wire ends. Lugs not
supplied.

• Use pliers, etc., to crimp lugs to wires.

4. Connect the wires to the terminal.

• Fix the wires securely with the terminal
screws.

Connecting the Speaker Output
Terminals

1. Expose the end of the speaker wires
using nippers or a cutter by about
10 mm and twist.

2. Attach lugs to speaker wire ends.
Lugs not supplied.

• Use pliers, etc., to crimp lugs to wires.

10 mm

Fuse (30 A)

Engine
compart­ment

Interior of
the vehicle

Drill a 14 mm
hole into the
vehicle body.

Insert the O-ring rubber
grommet into the vehicle
body.

Twist

Positive terminal

Fuse (30 A)

Battery wire

Ground wire

Lug

Lug

3. Connect the speaker wires to the
speaker output terminals.

• Connect the speaker wires, passing them

through the terminal cover.

• Fix the speaker wires securely with the termi-

nal screws.

4. Push on the terminal cover.

Using the Speaker Input

Connect the car stereo speaker output
wires to the amplifier using the supplied
speaker input connector.

• Do not connect both the RCA input and the
speaker input at the same time.

7 Connections when using the speaker

input

Speaker
output
terminal

Terminal cover

Terminal screw

Speaker wire

Twist

Speaker wire

Lug

Speaker output

Car Stereo

Speaker input connector
To speaker input terminal of
this unit.

White:
Left +

Gray:
Right +

White/black:
Left ≠

Gray/black:
Right ≠

GND terminal

Power terminal

Battery wire

System remote
control terminal

System remote
control wire

Ground wire