Aunex AP-4EQ User manual

AP-4EQ
4 Band Premium Performance Equalizer
Installation and Operation Manual
Please take time to thoroughly read through this manual to familiarize yourself with your new equalizer.
This will ensure that your equalizer will perform at its optimum capabilities.
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del producto que necesita. Haga clic en la pestaña Soporte y descargue su manual en español.

1
Congratulations and thank you for purchasing an Aunex
Premium In-Dash Equalizer with a Built-In Line Driver. This product
has been engineered and manufactured utilizing precision quality
partsandcraftsmanship. Improvementsinsoundqualityandsystem
performance will be greatly enhanced with the use of this equalizer.
To ensure maximum performance we highly recommend you have
your new Aunex product installed by an Authorized Aunex Dealer.
Should you decide to install this product yourself, please make
sure to read this manual thoroughly to familiarize yourself with
the necessary installation requirements and tuning procedures.
Please read your warranty and retain a copy of your purchase
receipt and original carton should your equalizer ever needs
to be serviced and warranted.
Visit our website for the latest information on all Aunex products
at: www.aunexusa.com. If you have any questions regarding
this product, please contact your Authorized Aunex Dealer for
assistance or call / email Aunex Technical Support
Department at [phone] / [email protected].
Caution: Continuous exposure to sound pressure levels over 100dB may
cause permanent hearing loss. High powered audio systems can produce
sound pressure levels that can exceed over 150dB. Please limit your
exposure to continuous high listening volumes.

2
Features of the AP-4EQ
• 4-Band In-Dash Equalizer; -18dB to +18dB level adjustment
o Center Frequencies: Bass (75Hz), Mid-Bass (500Hz),
Midrange (2.5kHz), High (10kHz)
• Line Driver with 9Volts Maximum Output
• Master Volume Control Knob
• Fader Control Knob
• Independent Subwoofer Level Control Knob
• Front Variable Subwoofer Frequency Knob (40Hz – 150Hz)
• Dual Input Source Selector - Main Input or Auxiliary Input
• Front 3.5mm Auxiliary Input
• Balanced Dierential Front, Rear, Subwoofer RCA Outputs
• High Level Speaker Input Compatible
• Low Level RCA Input Compatible
• Blue Backlight Illumination
What’s Included
• (1) AP-4EQ Equalizer
• (1) 2 Amp In-Line Fuse
• (1) 3 Pin Power Connector Plug
• (1) High Level Speaker Input Plug
• (2) Mounting Brackets
• (4) Self Tapping Screws
• (4) Machine Screws
• (4) Lock Washer
• (1) Instruction Manual
• (1) Sticker

3
Important Safety Considerations
• To prevent personal injury and damage to the unit, please read
the following instructions in this manual.
• This product is designed to use in vehicles with 12Volt,
negative-ground electrical systems.
• Install this product in a dry location away from your vehicles’
safety equipment (airbags, seat belt system, etc.). Water and
humidity may damage internal components.
• Use the included mounting accessories to secure this product
so that it does not come loose.
• Check before drilling to make sure you do not drill into any vital
vehicle system.
• Protect all system wiring from sharp metal edges.
• Do not disassemble or modify this unit; doing so will void your
manufacturer’s warranty.
Important Installation Precautions
Installation of mobile audio equipment requires experience.
Although this manual provides general installation procedures,
it will not show the exact installation method for your particular
vehicle.
If you do not have the required knowledge and experience,
we recommend that you have your equipment installed by an
Authorized Aunex Dealer.
• Turn o all stereo and other electrical devices before you begin.
• Disconnect the negative (-) lead from your vehicle’s battery to
avoid an electrical short.
• Check the mounting depth to make sure there is sucient room
for your installation placement preference.
• When running power cables through sheet metal it is best to use
grommets and loom to properly insulate the metal edges.

4
Mounting Placement
The AP-4EQ was designed to be installed in or near the
dashboard of most vehicles. The front panel was designed
so that the equalizer would be mounted ush to your vehicles’
dash. There are dash kits from many brands that allows for the
equalizer to be mounted alongside your headunit. Check with your
Authorized Aunex Dealer for additional information and options.
Other popular mounting options are under the dashboard or in
your glove compartment. For these methods, you will use the
supplied mounting brackets as shown below. Make sure there
are no items behind the area where the screws will be driven.
For optimum sound quality, it is highly recommended that you
purchase Aunex wiring accessories as they are designed to give
your equalizer and ampliers the high-quality signal it needs to
operate at peak performance levels. Aunex has everything from
RCA cables and power wire to speaker wire and battery connectors.

5
1. Main Volume: This knob controls the volume level of your Front
and Rear outputs. It is recommended that you set your radio
volume at the desired listening level and make your sound
adjustments from your equalizer.
2. Fader: This knob will allow you to fade the signal level between
your Front and Rear outputs. This will allow you to have Front
and Rear fading capabilities with only one pair of inputs.
3. Dual Input Selector: This button allows you to select the input
signal from either your main Head Unit or Aux Input.
4. Input Voltage Selector: On the top of the AP-4EQ is a switch
to select either Low Level RCA Input (left side position) or High
Level Speaker Input (right side position). The High-Level input
allows you to connect speaker outputs from our factory radio to
the equalizer without the need of a high to low level converter.
5. Subwoofer Frequency: This knob allows you to select the
center frequency range of your subwoofer output from 40Hz to
150Hz.
6. Subwoofer Volume: This knob controls the volume level of your
Subwoofer Output and is independent from the Main Volume
knob.
7. Equalizer Knobs: These 4 knobs allows you to control the Bass
(75Hz), Mid-Bass (500Hz), Midrange (2.5kHz) and High (10kHz)
frequencies with a 18dB of defeat or boost.
8. Auxiliary Input: This 3.5mm input jack allows you to connect
your phone or portable audio player directly to your equalizer. Be
sure to select Aux input mode when in use from the front
panel button.
Front Panel Controls
1 2 3 6 7 84
5

6
1. Power Connector: This connector has inputs for Ground,
Remote and Power.
a. Ground: Use the same gauge wire that is being used for the
Power connection and run your ground wire to this negative
terminal. Good ground points are from your battery, a ground
buss or a veried ground location that is clean. This will
minimize the possibility of noise induced into the system.
(Factory head unit ground is not recommended as it can induce
unwanted noise.)
b. Remote: Use a 22 to 18 Gauge wire from your head unit’s
remote turn-on (+12VDC Switched) and run it to remote terminal.
c. Power: Use the supplied in-line fuse and connect it to a
constant positive +12 volt source. Use the same gauge wire
that is used for the ground; preferably 18 Gauge or larger and run
it to the +12 Volt terminal.
2. High Level Input: If you are going to use High Level Input
instead of the Low Level RCA’s inputs, you will need to be set
the gains on your ampliers lower as the output voltage of the
AP-4EQ is stronger with High Level Input than Low Level RCA
Inputs.
Low Level RCA Connections: Aunex recommends using high
quality RCA Interconnects such as the Aunex AP RCA and AE
RCA series. Consult with your Authorized Aunex Dealer to see
what cable and length works best for your installation. (Note:
Avoid crossing your power and wire ground with your RCA
cables. This will help prevent noise interference.)
3. Main: Use this pair of inputs to connect your main source /
headunit.
Rear Panel Controls
1 2 3 4 5 6

7
4. Rear: Use this pair of outputs to connect to your rear amplier
or rear channels of your amplier.
5. Front: Use this pair of outputs to connect to your front amplier
or front channels of your amplier.
6. Subwoofer: Use this pair of outputs to connect to your
subwoofer amplier or subwoofer channels of your amplier.
The above example illustrates the most common use of
the AP-4EQ utilizing 3 ampliers and a headunit. The signal
connections from the headunit can be from either the
High-Level Input or the Low-Level RCA Inputs. Depending
on which input method you use, be sure to position the top
switch to the appropriate mode. It is recommended to not
connect the High-Level and Low-Level Input simultaneously.
Rear Panel Controls Continued
Installation Diagram
Ground
Remote
Fuse
Power / 12V Battery
Speaker or RCA
RADIO AMP. AMP. AMP.

8
Tuning the 4 Bands of equalization is set by your listening
preference as dierent music genre are produced with
dierent quality and dierent equalizations. The AP-4EQ was
designed to help you compensate these recording dierences by
allowing you to ne tune your system for your listening enjoyment.
The 4 Bands of equalization does not aect your
subwoofer channel as your subwoofer channel already has its
own independent frequency range and volume knob. Instead the
equalization bands will only aect the Front and Rear Outputs.
- Bass (75Hz Centered): Use this knob sparingly as most
coaxials speakers and components cannot handle 18dB of
boost. However, in some music you will nd that turning up this
knob will enhance the low frequency output.
- Mid-Bass (500Hz Centered): Use this knob to control
frequencies that are above subwoofer bass and below midrange
which is also called low order harmonics. This range is normally
associated with Male vocals, brass instruments.
- Mid-Range (2.5kHz Centered): Use this knob to control
frequencies that are associated with musical instruments and
female vocals. Over boosting this region can harm your hearing
as your ears are particularly sensitive to how voice sounds and
it’s frequency coverage.
- High (10kHz Centered): Use this knob to control the upper
frequency spectrum which is also known as the brilliance range.
Boosting this range can make a recording sound more Hi-Fi.
However over boosting this range can also cause excessive
hiss and listening fatigue.
Equalization Adjustments

9
Total Outputs 3
Total Inputs 3
Output Voltage 9 Volts Maximum
Frequency Response 10Hz – 50kHz
4 Band Eq. Center Freq. 80Hz, 500Hz, 2.5kHz, 10kHz
Defeat / Boost -18dB / +18dB
Variable Sub. Freq. 40Hz – 150Hz
THD + Noise < 0.01%
S/N Ratio A-Weighted > 110dB
Channel Separation 93dB @ 1kHz
Input Sensitivity 250mV – 10V
Input Impedance 6.2k Ohms
Operating Voltage 9 – 18 Volts DC
Fuse Requirement 2A (Included)
Dimensions (H x W x D) 1.0 x 7.0 x 4.2
Inches / MM 25 x 179 x 106
Technical Specications
*Due to continuous product improvements; specications and features are
subject to change without notice. Please visit www.aunexusa.com for the
most current information.
*This manual is the exclusive property of Aunex, Inc. Any reproduction of this
manual or use other than its intended purposes is strictly prohibited without
the express written consent of Aunex, Inc. ©Copyright 2020 Aunex, Inc.

10
Troubleshooting
Problem Solution
Equalizer does not
work; no LED’s on
1. Check to see if Power, Remote
and Ground is connected to the
equalizer
2. Check Power and Remote Turn-on
lead for proper +12 Voltage
Equalizer powers
up; no sound
1. Check to see if Power, Remote
and Ground is connected to the
equalizer
2. Check Power and Remote Turn-on
lead for proper voltage
3. Center the Fader knob
4. Push the source button on the
front panel to make sure you have
selected the correct input mode
5. Make sure your input switch on the
top panel is at the correct mode
Hissing noise from
speakers
1. Readjust your ampliers gains to a
lower voltage setting
2. Readjust your source unit volume
3. Make sure your RCA’s is routed
away from your Power and Ground
connections (Eq and Ampliers)
Distorted sound
from speakers
1. Readjust your ampliers gains to a
lower voltage setting
2. Readjust your source unit volume
3. Readjust your equalization knobs

11
California’s Proposition 65 (Prop 65) entitles consumers in
California to special warnings for products that contain
chemicals knows to the state of California to cause cancer, birth
defects or other reproductive harm if consumers are
exposed to such chemicals above certain threshold levels.
While this law is only for California and Aunex sells products to
consumers in California, Aunex is required to display this warning.
California Prop 65 Warning
Warning: This product can expose you to
chemicals which are known to the State of
California to cause cancer or birth defects
or other reproductive harm. For more
information visit www.p65warnings.ca.gov.
Limited Warranty – Electronic Processors
Aunex, Inc. warrants this product to be free of defects in
materials and workmanship for a period of 2 years from the original
purchase date. This warranty is non-transferrable and applies
only to the original purchaser from an Authorized Aunex Dealer.
Should service be necessary within the warranty period, Aunex will
at its discretion repair or replace the defective unit with a new or
remanufactured product at no charge. Damage caused by
misuse, abuse, accidental damage, product modication, failure to
follow installation instructions, unauthorized repairs will not be
covered under warranty. This warranty does not cover incidental or
consequential damages and does not cover the cost of having
the unit removed or reinstalled. Cosmetic damages by accident or
normal wear and tear are not covered under warranty.
Subsequent damage to other component will be not covered.
Warranty

12
Warranty will be voided if the product’s serial number has been
removed or defaced. Any applicable implied warranties are
limited in duration to a period of the express warranty as
provided in this manual beginning with the date of the original
purchase and no warranties whether express or implied shall
apply to this product thereafter. Some states do not allow limitation
on implied warranties; therefore, these exclusions may not
apply to you. This warranty gives you specic legal rights;
however, you may have other rights that vary from state to state.
All warranty returns should be sent to Aunex freight prepaid
and must be accompanied by proof of purchase; a copy of the
purchase sales receipt. All returns whether sent by the Dealer of
purchase or directly from the consumers must have a valid RMA
number (Return Merchandise Authorization). Returns without a
valid RMA number will be refused. The RMA number must
be clearly written on the outside of your return package.
Non-defective units will be returned to sender freight collect.
Customers are responsible for shipping charges and insurance
in sending products back to Aunex. Freight damage on returns is
not covered under warranty so be sure to package your return in
the original box or packaged securely in another box to prevent
possible freight damage. Warranty expiration on items without proof
of purchase will be determined from the manufacturing date code.
Products purchased outside of the United States of America
are covered by that country’s distributor and not by Aunex, Inc.
For Service Information in the U.S.A. and to obtain a Return
Merchandise Authorization number RMA) please call Aunex at
[phone].
Warranty Continued

Declare Your Independence!
Aunex, Inc.
13865 Magnolia Avenue, Unit C
Chino, CA 91710
T. [phone] / F. [phone]
8:30am – 5:30pm (PST – Pacic Standard Time)
www.aunexusa.com