Audiobahn A4KDN User Manual

4000 WATT RMS CLASS D

COMPETITION AMP

A4KDN

OPERATING INTSTRUCTIONS

PLEASE RETAIN MANUAL FOR FUTRE USE AND REFERENCE

QUALITY, RELIABILITY, & PURE BLISS

The Audiobahn Way

To bring the product to market that excites the consumer through
sound and vision from an orientation of integrity and customer service. We
make you look as good as you sound. We strive to take car audio to an
extreme the world has never seen, and a world that never stops evolving.

Audiobahn was established in 1997 with one long-term goal in mind,
"Build it Bigger, Badder, & Better, and the people will take notice!" We
back this statement with an engineering team that has brought home several
Innovations, Design & Engineering Showcase Awards, and a marketing team
from around the world that spends countless hours developing our no
compromise products to satisfy the most discriminating enthusiasts.

Our global manufacturing facilities feature ISO9002 ratings (the highest
level of quality control awarded in the electronics manufacturing industry), fully
robotic assembly lines and a state of the art, California based R & D
laboratory.

Due to overwhelming response from our competitors, and our goal to
participate in even more events this year, we created *"TEAM AUDIOBAHN."
This organization is designed to create a support network along with shirts and
perks for team members. "TEAM AUDIOBAHN" is not only for the diehard
competitor, but also for anyone that loves car audio as much as we do. With
four levels of play, one is right for you to get started in the Audiobahn family.

Our Technical Department and entire staff look to strive above and
beyond the rest of the pack by going that extra mile to help you out. Whether
you happen to be a veteran competitor, or a beginner car audio enthusiast
who does not know a voice coil from a spider. We are all her to help you get
the best system you can with what you have.

Judge for yourself, and remember what it's all about,

"If it's not

Bigger, Badder & Better, it's not Audiobahn." If audio is your life,

Audiobahn is the brand for you! We make you look as good as you sound.
People never stop trying to get the best product, so we will never stop making
it.

*To learn more about "TEAM AUDIOBAHN" please give us a call, see our website at

website at www.audiobahn.com, or email us at [e-mail] to learn about all the
details.

Table of Contents

Table of Contents

2

Introduction

Features and Specifications

Control and Functions

Planning / Mounting Your System

Adjusting and Tuning

Troubleshooting

Wiring Diagram

Warning and Disclaimer

Bridging 2 Amplifiers

3

4

5-10

11

12

16

15

17

13-14

Warranty

18-19

Introduction

Dear Customer,

Congratulations on your purchase of the worlds finest brand of car audio products. Here at
Audiobahn Inc. we are devoted to making our musical reproduction the very best, and we are
pleased you have chosen 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 Audiobahn product installed by an
Authorized Audiobahn Dealer, as we provide specialized training through our Audiobahn
Installer Training Programs. Please read your warranty, keep your receipt, and original carton
for possible future use.

Great products and proper installation are only a small piece of the puzzle when it comes to
your system. Make sure that your installer is using only 100% authentic installation accessories
from the Audiobahn Connections. The Audiobahn line has everything ranging from the smallest
terminal, to power wires up to 0 gauge, and 4 channel RCA cables.

To get a free brochure on Audiobahn products in the U.S. call [phone] or e-mail us at
[e-mail].

WARNING

Continuous exposure to sound pressure levels over 100 dB may cause
permanent hearing loss. High powered autosound systems may produce sound
pressure levels well over 135dB. Need we say more! Use common sense.

If after reading this manual, you still have questions regarding your product, we
recommend that you see your nearest Audiobahn Dealer. A list of Authorized
Audiobahn Dealers can be found on our web page. If you need further assistance, feel
free to call us at [phone] and ask for the Technical Department. Be sure to have
the model number, date of purchase, and invoice number available when you call.

The model number can be located on the outside of the carton. Record this in the space
provided below along with the date of purchase. It is a good idea to keep your receipt
with this, as you will need it in the case of a warranty repair or exchange.

Model Number:___________________

Date of Purchase: _____________________

3

Features and Specifications

4

> Class D MOSFET Amplifier
> Multi-Stranded Power Supply Toroids
> Double-Sided Glass Epoxy Circuit Board
> Remote Bass Control with BLUE Backlight Knob
> Large Display Volt meter with BLUE Illumination
> 4-Way protection circuitry: Thermal, Short circuit, Over load , and DC Offsct
> Dual Cooling FANS
> Cobalt BLUE Illumination
> Chrome Flame FAN Grills
> High Gloss Chrome-Plated Finish
> Nickel-plated Block Terminals
> RMS Power , INTO 4 Ohms 2000W Mono
> RMS Power , INTO 2 Ohms 3000W Mono
> RMS Power , INTO 1 Ohms 4000W Mono
> THD at 1 Watt , 4 Ohm 0.05%
> Input sensitivity 200mV-8V
> Frequency response, at 1 Watt, 4 Ohm 15Hz~150Hz (+/-3dB)
> Variable Low Pass Filter 50Hz~150Hz, 24dB/Octave
> Variable Subsonic Filter 15Hz~40Hz, 24dB/Octave
> Variable Bass Boost Control 0~ +18dB
> Phase Shift Control 0~180 degree
> Input Impedance 10K Ohm
> Source Voltage (Automobile battery) 11~16V DC
> Maximum DC current (1 Ohm, 1% THD +n) 456 amperes DC
> Dimensions : WxHxL

11.97" x 2.76" x 23.54"

NOTE:

As the A4KDN amplifier is a competition grade Class D Amplifier, no
fuses are included on the amplifier. It is recommended to fuse the
power wire no further then 18” away from the battery. The fuse rating
you need to use will vary depending on the setup of your system,
impedance the amplifier is running, and use of the system.

Controls and Functions

�

Controls and Functions

�

This plug connects the amplifier and the remote bass knob using the supplied cable.

This control adjusts the amplifier's input sensitivity. The input sensitivity is variable from 200 Millivolts to 8
volts. Turning clockwise increases sensitivity. Turning counterclockwise decreases sensitivity. This knob
is not a volume control for the amplifier. The amplifier can be driven to full power with a wide range of
input signals. A lower signal level will require increased sensitivity to reach full power. A higher signal
level will require decreased sensitivity.

These inputs are for signal cables from the source. Always use high quality, shielded RCA cables.

1. Bass Boost Gain Remote Control

2. Input Sensitivity Control

3. Low level Input RCA Jacks

Controls and Functions

�

The LINE OUT allows you to build a multiple amplifier system without having to use splitter cords or
Y-adapters to distribute the signal. Now it is simply a matter bringing one set of RCAs into the first
amplifier, then using the line out RCA jacks as the feed to the next amplifier.

By using the bass boost function, bass notes at 45Hz are emphasized as much as 18dB.

Allows you to change the phase of your subwoofer from 0 to 180 degrees to help compensate for timing
differences between drivers.

4. Low Level LINE OUT RCA Jacks

5. Bass Boost Control

6. Phase Shift Control

�

Controls and Functions

For use as a dedicated subwoofer channel, set the filter switch to the "LPF" (Low Pass Frequency).
Adjust the variable crossover frequency with control knob as desired. The amplifier input circuit filters out
everything above 50Hz ... 150Hz (dependant on the adjustment of the frequency control), so only the
lowest bass notes are amplified.

The sub sonic control will cut all frequencies below what it is set to from going to your sub(s). This will
prevent your subs from playing any frequencies that may harm them.

7. Low-Pass Filter Control

8. Sub Sonic Control

9. Bridged Connection

This is the connection used to bridge 2 two of the same class D amplifiers together. Later in this manual it
is explained how to bridge the amps and what settings to use.

CLIPPING INDICATOR

Included on the front of this amplifier is a clipping indicator. You will
notice that the lights on the front of the amplifier light up blue. This
happens during normal good operation. If the light start to turn red, it
indicates that the amplifier is clipping. This can lead to permanent
damage to both your amplifier and any speakers hooked up to it.
Clipping can be caused by low voltage supply to the amplifier, having
the gain / level or bass boost setting adjusted to high, or too low of a
ohm load causing the amplifier to overdrive itself.

Controls and Functions



These terminals are used to wire your subwoofer(s) to the amplifier.

To avoid unwanted ignition noise caused by ground loops, it is essential that the amplifier be grounded to
a clean, bare, metal of the vehicle's chassis. This metal surface should be solid, strong and connected
directly to the frame of the car.

Note: GROUND WIRE SHOULD NOT BE EXTENDED MORE THAN 3 FEET (1 METER)

Due to the power requirements of the amplifier, this connection should be made directly to the positive (+)
terminal of the battery. For safety purposes, install an in-line fuse holder (not included) as close to the
battery positive (+) terminal as possible with an ampere rating not to exceed the total value of fuses in the
amplifier.

10. Speaker Terminals

11. B- Terminal (Chassis Ground)

12. B+ Terminal (Battery Positive)




Controls and Functions



The remote terminal needs to be wired to the car's stereo or source unit remote turn on wire. This
amplifier is turned on remotely when the vehicle's stereo is turned on.

NOTE: iF YOUR RADIO DOES NOT HAVE A +12 VOLT OUTPUT LEAD WHEN THE CAR IS TURNED
ON, THE "REMOTE" TERMINAL ON THE AMPLIFIER CAN BE CONNECTED TO THE VEHICLE'S
ACCESSORY CIRCUIT THAT IS LIVE WHEN THE KEY IS TURNED ON.

PWR (Power): This BLUE LED will illuminate when the amplifier is turned on. If it fails to illuminate, check
the fuses and power connections to the amplifier.

PROT (Protection): The amplifier protection circuitry will disable the amplifier if there is an imput overload,
short circuit, or extremely high temperature conditions are detected. When the protection mode is in
operation, the LED indicator on the side panel will be illuminated RED, indicating the amplifier has gone
into a self-preservation mode.

If you observe that the protection LED is lit, please check the system carefully to determine what has
caused the protection circuit to engage. The amplifier can be reset by turning the remote power off and
then on again. If the amplifier shut down due to a thermal overload condition, please allow time for the
amp to cool down before restarting. If the amplifier shut down because of an input overload or short
circuit, be sure to repair these conditions before attempting to power up the amplifier again.

13. Remote Turn-on Input

14. LED Indicators

b. Are your components matched? The RMS power rating of your speakers must be
equal or greater than the amplifier's. They also must be 1-8 Ohms impedance
(this information is normally printed on the speaker magnet).

c. Consider both the length of your leads, and routing when determining the mounting
location. Pre-Amp input Jacks require a length of high quality shielded male to male
RCA patch cord.

NOTE:

DISTORTION LEVEL IS CONSIDERABLY LOWER FROM PRE-AMP (LOW LEVEL)
OUTPUTS, THAN SPEAKER

(HIGH LEVEL) OUTPUTS.

Before beginning the installation, consider the following:
a. If you plan to expand your system by adding other components sometime in the
future, ensure that adequate space is left, and cooling requirements are met.
If your radio/source is equipped with Pre-Amp outputs, it is possible to utilize them
to drive an Amplifier and connecting (amplifier) to the 2 rear speakers.
Then, use the built-in power of your radio to drive the 2 front speakers.

a. Select a suitable location that is convenient for mounting, accessible for wiring, and
has ample room for air circulation and cooling.

b. Use the amplifier as a template to mark the mounting holes. Remove the amplifier
and drill holes. Use extreme caution. Inspect underneath the surfaces before drilling!

c. Secure the amplifier using the screws provided.

The mounting position of your amplifier will have a great effect on its ability to dissipate
the heat generated during normal operation. It has an ample heat sink for heat
dissipation, and also is designed with a thermal shut-down (for heat protection) circuit,
having enough air directed over the cooling fins will improve heat dissipation dramatically.
DO NOT enclose the amplifier in a small box or cover it so that air can not flow around
the fins. Temperatures in car trunks have been measured as high as (155 F) in the
summer time. Since the thermal shut-down point for the amplifier is (158 F) it is easy
to see that it must be mounted for maximum cooling capability. To achieve the maximum
advantage of convection air flow in an enclosed trunk, mount the amplifier in a horizontal
position. Cooling requirements are considerably relaxed when mounting inside the
passenger compartment since the driver will not allow temperatures to reach a critical
point. Floor mounting under the seat is usually satisfactory as long as there is at least 1
inch (2.54 cm) above the amplifier's fins for ventilation.

CAUTION: Before connecting any wires to the amplifier, disconnect the ground lead from

the battery. Leave the ground lead disconnected until you are done wiring the

amplifier.

Planning Your System

Mounting Your System

Planning and Mounting Your System

11

Wiring Diagram



Bridging 2 Amplifiers



Master Slave

BRIDGED

BRIDGED

IF BRIDGED SWITCH POSITION IS ON SLAVE, ALL CONTROLS ARE NON-FUNCTIONAL.
ALL CONTROLS ARE NOW CONTROLLED BY THE MASTER AMPLIFIER.

HEAD UNIT

DES. 423,503

Bridging 2 Amplifiers



US 6,656,000B2

When bridging the amps together follow these wiring instructions:

1. Positive (+) of the MASTER amp goes to Positive (+) of the sub

2. Positive (+) of the SLAVE amp goes to the Negative (-) of the
sub

3. Connect the Negative (-) terminals of both amps together

TURNING ON THE AMPLIFIER

The amplifier automatically turns on a few seconds after you turn your vehicle's ignition
switch to ACC or turn on your auto sound system (depending on how you have wired
the system). The POWER indicator on the top of the amplifier illuminates when the
amplifier is on.

Important: Your amplifier requires 30 amps or more of power from your vehicle's
battery during operation. To protect your battery from discharging, do not operate the
amplifier unless your vehicle is running.

Note: Your amplifier temporarily shuts down if it gets too hot, then restarts automatically
once it cools.

NOTE Raising the LPF frequency allows higher frequencies to reach the bass speakers
while blocking lower frequencies from midrange speakers. Lowering the LPF frequency
allows lower frequencies to reach the midrange speakers while blocking higher
frequencies from bass speakers.

+ 10dB

+ 20dB

0dB

- 10dB

- 20dB

- 30dB
10 50 100 500 1K 5K 20K 50K

FREQUENCY (Hz)

RESPONSE (dB)

FREQUENCY RESPONSE BASS BOOST ON

Adjusting and Tuning

For the best performance, you must set GAIN (4V/0.2V) on the side of the amplifier to
adjust the level of the audio signals that enter the amplifier.

1. Use a screwdriver to turn GAIN (4V/0.2V) fully counterclockwise to 4V.

2. Turn the auto sound system's volume control to about one-third of its full range.

3. Adjust GAIN (4V/0.2V) to a comfortable listening level.

4. Turn up the auto sound system's volume control until the sound begins to distort.
Then immediately turn the volume down to a point just before where the distortion
began.

Caution Never turn up the auto sound system's volume control more than needed
to adjust the audio level (More than two thirds of its maximum volume).

5. Adjust GAIN (4V/ 0.2V) until the sound is at the maximum level you want the amplifier
to produce.

6. Adjust the auto sound system's volume control to a comfortable listening level.

ADJUSTING THE AUDIO LEVEL

15

Separate speaker wires and

insulate

Speaker wires short

STATUS
LAMP ON

Temperature shut down

Be sure proper speaker load
impedance recommendations
are observed.
(If you use an ohmmeter to check
speaker resistance, please
remember that DC resistance and
AC impedance may not be the
same.)

AMP
TURNING OFF
MEDIUM/HIGH
VOLUME

impedance

Check speaker load

Reverse Left and Right RCA inputs
to determine if it is occurring
before the amp.

Check Audio Leads

NO SOUND
IN ONE
CHANNEL

Inspect for short circuit or an
open connection.

Check Speaker Leads

Fuse broken

wire with receiver on

No power to remote

AMP NOT
SWITCHING
ON

No power to power wire

Is the Diagnostic
LED illuminated ? ( YES )

NO SOUND Is the power

LED illuminated ?
( NO )

Check fuses in amplifier.
Be sure Turn-on lead is connected
Check signal leads. Check gain
control.
Check Tuner/Deck volume level.
Clean contacts on fuse holders.

CHECK POINTS CURESYMPTOMS

Check for speaker short or
Amplifier overheating.

Repair power wire or connections.

Turn radio down

Replace fuse.

Check connections to radio.

Troubleshooting

16

Investigate the layout of your automobile thoroughly before drilling or cutting any holes.

Take care when you work near the gas tanks, lines, hydraulic lines, and electrical wiring.
Do not use the power amplifier unmounted. Attach the system securely to the automobile
to prevent damage, particularly in the event of an accident. Do not mount the system
so that the wire connections are unprotected or are subject to pinching or damage
from nearby objects.

The +12V DC power wire must be fused at the battery positive terminal connection.
Before making or breaking power connections at the system power terminals,
disconnect the +12V wire at the battery end. Confirm your radio/head unit and/or other
equipment is turned off while connecting the input jacks and speaker terminals.
If you need to replace the power fuse, replace it only with a fuse identical to that
supplied with the system. Using a fuse of different type or rating may result in damage to
this system which is not covered by the warranty.

Disclaimer

Specifications are subject to change without notice.

For the most updated Specifications call Audiobahn,

your local Authorized Audiobahn Dealer,

or check

the Audiobahn website.

www.audiobahninc.com

Warning / Disclaimer

Technical Assistance(800)488-8595 /[e-mail]

17

WARNING

Audiobahn Consumer

Product Warranty Policy

Audiobahn products are manufactured with the highest quality components and some of
the most advanced technology available. Because of this, we recommend that you have
your new products installed by an Authorized Audiobahn Dealer.(A list of Authorized

Audiobahn Dealers can be found on our web page).

Warranty Period: One year from the original date of purchase.

Warranty Coverage: This warranty covers manufacturer defects only. The warranty is

applicable to the original purchaser, and is non-transferable. You must have a receipt from
an Authorized Audiobahn Dealer that shows the location of purchase, price paid, and
date of purchase.

(Products purchased by consumers from an Authorized Audiobahn Dealer outside the
United States, are covered only by that countries Distributor and not by Audiobahn).

Notes:

Complete subwoofer enclosures (Audiobahn will replace defective subwoofers,
plexiglass, or neon only. Do not send the entire enclosure, unless the enclosure is
defective itself. You must receive prior authorization and an RA# before sending in any
complete enclosure).

Audiobahn will only replace L.E.D.(s) found to be defective at the time of purchase.

Audioba h n w arranti e s do not cover th e f o l lowing :

Any product not purchased from an Authorized Audiobahn Dealer (including Internet
dealers)

Damage caused by abuse, misuse, accident, water / flood, or theft (including any
cosmetic damage to the body of the product)

Damage caused by improper installation

Any cost or expense related to removal or reinstallation

Any unauthorized services

Any product that has the serial number removed, altered, or defaced

Subsequent damage to any other components

Pinched, cut, or stripped wires

Any product that is new, and/or found to be in working condition

L.E.D. indicators on electronics

Warranty

Technical Assistance [phone] /[e-mail]

18

How to receive warranty service: Contact your local Authorized Audiobahn Dealer, or call Audiobahn at
[phone] between the hours of 9:00 AM and 5:00 PM PST.

If you are having problems with your system, we recommend you check the product carefully and
thoroughly to confirm that the product truly has a manufacturer defect; as opposed to abuse, or other
components in the system causing the failure. This might include having an Authorized Audiobahn
Dealer look at the product to confirm the source of the problem. Any product found to have a
manufacturer defect will be replaced with a new piece of the same or similar model, or repaired at the
discretion of Audiobahn. Any product found to have no manufacturer defect will be returned to the sender
at their cost.

You must acquire a Return Authorization Number (RA#) prior to returning ANY product to
Audiobahn. That Return Authorization Number (RA#) must be prominently and clearly marked on the

outside of the shipping carton, or product delivery will be refused (no exceptions will be made).

Please note: All shipping and handling (to and from) charges will be the sole responsibility of the
consumer.

Please record and keep your Return Authorization Number (RA#) in the event that further communication
is required.

Return Authorization Number (RA#): ______________________________

Date product was sent: ______________________________

Warranty Continued

Technical Assistance [phone] /[e-mail]

Brea, CA 92821

114

So

u

th Berry St.

Audiobahn Headquarters

Phone [phone] Fax. [phone]

Pacific Coast Time : 9am-5pm Mon. - Fri.

[e-mail]

Contact Information

19