Clarion APX401.4 User Manual

4-CHANNEL POWER AMPLIFIER

OPERATION

INSTALLATION

MANUAL

4 Channel Power System Amplifier

TABLE OF CONTENTS

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Input Connections and Audio Controls . . . . . . . . . . . . . . 3

Connections for Power and Speakers . . . . . . . . . . . . . . . 5

Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Mounting Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Wiring Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Setting the Gain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Setting the Crossover . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Setting the Bass Boost . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Final System Checks . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Product Specs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Warranty Information . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

INTRODUCTION

The Clarion APX401.4 is a full-featured four-channel amplifier incorporating
the following features:

• Full frequency response with low distortion and exceptional signal to noise
performance.

• Advanced circuitry design features bridgeable and mixed mode operations
for use in a variety of 4, 3 or 2 channel audio systems.

• Independent front and rear, low-pass or high-pass electronic crossovers each
with a 12dB per octave slope and full adjustment range (from 55Hz to 550Hz
Front and 55Hz to 5.5kHz Rear) to aid in any audio system configuration.

• Variable bass boost circuit to reinforce low frequency signals that maybe
lost due to subwoofer box design.

• Adjustable input level controls with ground loop isolation, which allows a wide
range of input signals.

• Remote turn-on with “soft start” muting to prevent turn-on “thump”.

• Pulse-width modulated (PWM) MOSFET power supply with low AM RFI
and protection circuits for overheating and speaker shorts.

• 2 ohm load capacity to drive a variety of speaker systems.

• Gold-plated input/output connectors and an external automotive type fuse

• Aluminum heat sink for efficient heat dissipation.

• Low profile, compact size for space limited installations.

ABOUT THE MANUAL AND WARRANTY

To start enjoying your new Clarion four-channel amplifier, please read the
instructions stated in this manual. Keep all instructions for future reference.
Also, save your original sales receipt as proof of purchase.

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Owner’s Manual

Owner’s Manual

DESCRIPTION

The Clarion APX401.4 4-channel car audio amplifier is an excellent choice for
creating a variety of multi-channel sound systems. The amplifier features flexi­bility of 2, 3 or 4 channel system by a flip of a switch. You can also configure
the front or rear amplifier sections for a mixed mode operation to drive a set of
satellite speakers and/or subwoofer.

The built-in 12 dB per octave electronic crossover lets you custom tailor the
sound of the front and rear channels, using two independent filters with
adjustable crossover frequencies for high-pass or low-pass filtering.

The amplifier also uses an unregulated MOSFET power supply for superior
control of output wattage. A toroid-coil transformer yields maximum power
transfer with minimal heat loss. Extensive circuit design keeps AM RFI at low
levels, so you won’t hear unwanted noise when the level is cranked up.
Protection circuits safeguard the amplifier when overheating, speaker shorts,
or improper load conditions occur.

All connections and controls are on the end panels and are easy to under­stand. Gold-plated RCA and barrier connectors are used to ensure the best
electrical connection for your system. Integrated into the endpanel is an
external automotive fuse that is easy to replace.

INPUT CONNECTIONS AND AUDIO CONTROL

The front panel of the APX401.4 contains connections for RCA Inputs and
Audio Control as shown below.

Figure 1-

1. Front RCA Input Jacks

2. Rear RCA Input Jacks

3. Front Gain Control

4. Rear Gain Control

5. Bass Boost Control

6. Rear Channel Input Selector

7. Front Mode Switch

8. Rear Mode Switch

9. Speaker Level Inputs

10. Front Frequency Control

11. Front X-Over Mode Switch

12. Rear Frequency Control

13. Rear Multiplier Switch

14. Rear X-Over Mode Switch
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4 Channel Power System Amplifier

The Input Connections are gold-plated RCA Jacks and are labeled as FRONT
RIGHT, FRONT LEFT, REAR RIGHT and REAR LEFT. The Gain Controls
provide a wide adjustment range to accommodate output levels from any
brand of source unit.

• Gain Controls - Seperate Front and Rear Gain Controls allow you to set the
nominal operating level of the amplifier. The amplifier’s range, 250mV to 2.5V
for RCA inputs or 500mV to 5V for speaker level inputs, can accommodate
input levels from virtually any brand of source unit.

• Bass Boost Control - The amplifier also features a “high-Q” (i.e. narrow
frequency band) Bass Boost circuit. It acts much like an equalizer, with
adjustable gain (from 0 to +18dB) fixed at 45Hz. Use this feature to tune low­frequency audio response to compensate for a less than ideal subwoofer
enclosure design. The added boost produces rich, full bass tones that are
normally difficult to reproduce in the car audio environment. NOTE: If Bass
Boost is undesired, set Bass Boost to 0dB.

High-pass/Low-pass Filter Controls

• Freq (Hz) Controls - The front crossover frequency is fully adjustable
between 55Hz and 550Hz. The rear crossover frequency is fully adjustable
between 55Hz and 5500Hz (via the Rear Crossover Frequency Multiplier) for
a wider range of crossover points. Use this feature, along with your speaker
manufacturer’s recommended crossover frequencies, to quickly design a
more advanced system. NOTE: If either of the X-Over Mode Switches is set
to OFF, varying the Freq (Hz) Control will produce no effect.

• Rear X-Over Frequency Multiplier Switch - When engaged, this switch
increases the crossover frequency of the rear channels by a factor of 10.
Example: If the Freq (Hz) dial is set for 240Hz, pushing in the multiplier
Switch changes the setting to 2400Hz.

• X-Over Mode Switches - These switches are equipped with 12dB per
octave electronic filters for precise frequency attenuation with minimal phase
distortion. Each filter is activated by sliding the X-Over Mode Switch to either
LP or HP.

• Output Mode Switches - These switches allow you to set the output mode
for front and rear channels. Stereo output allows full left and right stereo oper­ation. Bridged Mode uses a single input (Right In) to produce a bridged output
that is useful in high powered systems. L + R (sum mono) allows a stereo
input to be summed into a mono output.

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Owner’s Manual

• Rear Channel Input Select - This switch allows the flexibility of using either
2 or 4 inputs to operate the amplifier.

• Speaker Level Inputs - These provide connections for a high-level stereo
source. These connections are provided for installations when the source unit
does not have RCA outputs.

WARNING: When using the speaker (high-level) inputs, the Black wire must
be grounded at the radio. Failure to do this will result in noise and/or improper
operation.

CONNECTIONS FOR POWER AND SPEAKERS

The rear panel of the APX401.4 contains power and speaker connections as
shown below.

Figure 2-

1. Left Front Speaker Output

2. Right Front Speaker Output

3. Remote Turn-on Input

4. Ground Input

5. Battery + 12v Input

6. 40 Amp Fuse

7. Left Rear Speaker Output

8. Right Rear Speaker Output

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