Audiocontrol DQX User Manual

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DQX

Stereo One-Third Octave
Digital Equalizer/Crossover

Owner’s Enjoyment Manual

AudioControl

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22410 70th Avenue West • Mountlake Terrace, WA 98043 USA

Phone [phone] • Fax [phone]

www.audiocontrol.com

AudioControl®

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Table of Contents

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

Key Features and Highlights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Quick Installation Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

A Guided Tour of the DQX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Placement and Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Power Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Audio Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Level Matching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11

Navigating the DQX menu screens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Equalization Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

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Setting the DQX crossover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Graphic versus Parametric Equalization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Owner’s Enjoyment Manual

AudioControl®

Owner’s Enjoyment Manual

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Introduction

Welcome to the world of AudioControl’s perfor­mance digital signal processing . A magical combi­nation of AudioControl’s lengthy experience in
performance signal processing design combined
with state-of-the-art Digital Signal Processing
(DSP) technology. You now have in your posses­sion the DQX, an extremely powerful thirty-band,
one-third-octave stereo and parametric digital
equalizer with a 24 dB/octave Linkwitz-Riley
crossover. Whether you are a die-hard sound-off
competitor or simply enjoy great music, you will
definitely appreciate how the DQX makes your
performance autosound system sound even better.

Now before you start salivating too much just
thinking about the benefits of the DQX, take a
few minutes to sit back, have a latte’, decaffeinated
if necessary, and read through this manual. It
contains lots of useful facts and information - ­and besides, we spent a lot of time writing it!

KEY FEATURES OF THE DQX

Here are some of the cool features that are en­closed in this magical box:

• 30 bands of constant-Q equalization

• Dual, fully-adjustable Parametric

• equalizers

• Three-way 24 dB/octave electronic

• crossover

• Eight non-volatile memories

• 24 bit digital signal processing

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AudioControl®

FEATURES AND HIGHLIGHTS

Constant-Q equalization controls: Car

interiors vary widely in size and acoustic make­up. In addition doors, kick-panels, and rear decks
don’t make the best location for speaker place­ment causing your high performance speaker
system to sound somewhat lackluster. The DQX
offers thirty precise equalization controls spread
equally across the audio spectrum at one-third
octave increments for maximum control. Each
equalization filter utilizes a precise constant-Q
topology, traditionally utilized only in the highest
performing professional audio products.

Parametric Equalization Controls: In
addition to the thirty, one-third octave controls,
the DQX also offers two, fully-adjustable paramet­ric equalization controls. With the DQX’s para­metric controls you select a center frequency, dial
in the ideal bandwidth and apply the appropriate
amount of boost or cut. The precise filtering of the
DQX allows you to select bandwidths as narrow as
1/12 octave!

Programmable 24dB/Octave Three-way
Crossover: With digital programmability, the

three-way electronic crossover in the DXS easily
configures to almost any high-performance
mobile audio system. By simply pressing a few
buttons, you can select almost any crossover
frequency imaginable. The 24dB/Octave
Linkwitz-Riley (a couple of real nice audio engi­neers) design is normally reserved for the best
home and professional systems, but now this
state-of-the-art crossover is yours in the DQX.

Programmable Frequency Match (PFM)
Filter: This programmable low cut filter allows

the system designer to custom tune the bass
response of the speaker system. Smaller woofers
can be protected against the voice-coil-charring
bass they are too small to reproduce. Tuned
(Ported) subwoofers benefit by having the fre­quencies below their tuning cut off to reduce
distortion and save system power.

Non-volatile memories: The DQX has the
ability to allow the user to set and store up to
eight different system (equalization/crossover)
settings in individual memory locations.

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24 bit Digital Signal Processing:

AudioControl’s digital signal processors use a
special 24 bit DSP (digital signal processor) that
was specially designed for equalization and other
dynamics processing. In addition, matching 24
bit A/D - D/A converters are incorporated for
maximum sound quality.

Bulletproof Warranty: The most important
feature of all. Every AudioControl product is
selflessly designed and manufactured by the
occupants of our rainforest factory. We take every
effort to ensure that you will have many years of
enjoyment out of your DQX. To ensure the perfor­mance of this new Digital product, we highly
recommend that you allow your authorized
AudioControl dealer to perform the installation.
Not only do they have all the right knowledge
and tools, but in the unlikely chance your DQX
should stop working, we will back it with a lim­ited five years parts and labor warranty. Should
you choose to install it yourself we will still give
you one-year parts and labor warranty. To activate
your warranty, you need to FILL OUT AND SEND
IN YOUR WARRANTY CARD!

We also recommend that you save your invoice or
sales slip as proof of installation and ownership.
Not only is it necessary for warranty purposes, but
should your DQX “disappear” one day while your
car is parked at your local latte’ stand, you will
find insurance companies very unforgiving
without proof of purchase.

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AudioControl®

QUICK INSTALLATION
INFORMATION -

For those of you short on time, but high on ambi­tion, we offer the following section to speed up
your installation of the DQX:

1. The DQX needs to be installed in the signal path
between your source unit and your external
amplifier(s). If this is not obvious to you, quickly
pack up your DQX and run to your nearest autho­rized AudioControl dealer to have them perform
the installation. You will thank us later.

2. Physically mount the DQX in a location that
keeps it away from soda spills, food crumbs, and
curious fingers. However you will want to select a
location that allows you to see the display and
access the equalization/crossover controls during
setup.

3. Hook up +12 volt power, ground, and remote
turn-on. If you need to know more, then read on.
Heck, if you don’t think you need to know more,
you should still read on, because you can never
know too much.

4. Adjust the “Input Level” control on your DQX
to match the source unit’s output and then adjust
the “Output Level” controls to match with your
amplifier inputs.

Note: You will want to turn the gains on your
amplifiers DOWN to maximize your systems
performance.

5. Select the desired crossover points for the
“Mid/Hi”, “Lo/Mid”, and “PFM”.

6. Now comes the fun part. Set your equalization
controls to where your system sounds the most
balanced yet dynamic. More about this in the
section titled “Adjusting Your Equalizer”… and you
thought you would not have to read the rest of
the manual. Hah!

7. Last but not least, you will want to save your
system settings in one of the eight memory
locations.

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Figure 1: Basic DQX System

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AudioControl®

A GUIDED TOUR OF DQX

1) Inputs: The DQX has two RCA inputs that need

to get their audio signals from the main source unit.
If your source unit has multiple outputs (like a front,
rear, and/or subwoofer) you should only connect the
front or rear outputs to your DQX.

2) Input Level: This knob allows you to maximize
the signal level from your source unit that goes into
your DQX to achieve maximum signal to noise. Keep
in mind, that despite what the literature says, most
aftermarket source units produce a relatively low
voltage signal when it comes to playing music at
normal levels.

3) Input Maximized Indicator: This nifty LED
light indicates that you are supplying the DQX its
maximum amount of signal voltage. If the LED
indicator never comes on, don’t assume that it is not
working (since LED’s rarely break) but you might
consider adding a line driver to your system.

4) Output Level Controls: Although your DQX
has the ability to increase your signal voltage, your
amplifiers may not necessarily accept that much
signal. These controls allow you to regulate the
proper amount of pre-amp signal from the DQX to
the amplifiers.

5) Equalization Overload Indicator: This
convienient LED indicates when the DSP (digital

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signal processor) of your DQX is clipping or distorting.
The usual cause of this is having the “Input Level”
turned up too high or you have boosted too many
frequencies on your equalizer.

6) Select: This allows you to select one of the various
equalization, crossover, or memory modes of your
DQX.

7) Navigation Arrows: These multi-function
buttons perform a number of functions, depending
upon which mode your DQX is in. You can do any­thing from changing crossover frequencies to apply­ing boost or cut to your equalization filters. However,
if you get the high score, you cannot enter your
initials!

8) Output Voltage Indicators: These brightly
colored LED’s indicate the level of signal voltage that
is coming out of the various outputs of your DQX.

9) Outputs: These RCA connectors should be con­nected to the next components after the DQX, usu­ally an amplifier. Do not connect any speakers
directly to your DQX or to any home appliances, like
your toaster.

10) Power Connections: This nifty connector is a
godsend to those who have tried to wire up their gear
with their body crammed in the trunk. You can wire
up the power, ground, and remote turn-on from the
convenience of outside your car and then casually
plug it into your DQX.

DQX Digital EQ/XoverDQX Digital EQ/Xover

DQX Digital EQ/Xover

DQX Digital EQ/XoverDQX Digital EQ/Xover
By AudioControl(r)By AudioControl(r)

By AudioControl(r)

By AudioControl(r)By AudioControl(r)

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Figure 2: Top view of DQX

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AudioControl®

INSTALLING THE DQX

Up to this point everything you have read has
served to educate you on the operations of DQX.
We are sure that you are chomping at the bit to
install DQX so we recommend you read the
following sections very carefully.

A. Placement & Mounting of your DQX
Placement: The DQX needs to be installed in

the signal path after your source unit but defi­nitely before your amplifiers and or any active
crossovers. The chassis is usually mounted in the
rear of the vehicle, as close to the amplifiers as
possible.

Mounting: Once you have selected a perma­nent mounting location, position the unit and
mark the appropriate mounting holes with a felt­tip pin or scratch awl. Before doing anything else,
make sure you are not about to drill a hole in a gas
tank or pierce any existing wiring. Nothing ruins
your day more than an expensive repair bill. Drill
a few small pilot holes and secure the chassis of
the DQX with self-tapping screws.

B. DQX Power Wiring
Remote Turn-On: Connect a 22 to 18 gauge

wire from the head-unit’s remote turn-on to the
“Remote” connector on the DQX .

Positive(+12V) Connection: Insert a 12-18
gauge wire into the connector labeled “Power” on
the nifty connector of your DQX. Connect it to a
good constant source of 12 volts (we suggest the
battery), fused at 2 amps.

Ground Connection: Use the same gauge wire
as you did for the positive connector and run it
from the “Ground” connector on the DQX to the
negative terminal of the battery, a ground bus, or a
verified ground location. The factory head unit
ground is not a good ground! When the electrical
connections are complete, you may reconnect the
negative terminal to your battery.

WARNING: Failure to disconnect the

negative terminal of your battery prior to

the installation of your DQX can result

in a warm tingly feeling.

Figure 3: Back view of DQX with power connectors and RCA’s

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C. DQX Audio Wiring

Planning: As you may already have guessed, there
are numerous ways to configure the DQX in your
audio system. Spend a little quality time planning
out your system and even sketching it out on
paper. The following diagrams are just a few of the
system options:

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Figure 4: DQX in a two-way system

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Figure 5: DQX with a FOUR.1

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D. Level Matching

If you have ever listened to a friend’s “killer” car
audio system and heard lots of hiss, clicks or pops,
then you have experienced an improperly level
matched system. When a performance
autosound system is properly level matched, you
should get the maximum output from your
source unit and amplifiers without any clipping
or that annoying hiss! The following steps will
help guide you through the process, although at
the end of the day, your ears will be your guide!

1) Set your source unit’s fader and balance controls
to their center positions.

2) Disconnect the output RCA connections be­tween your DQX and the amplifier(s)...otherwise
get some ear plugs.

3) Start playing some relatively dynamic music
and set the volume on your source unit to about
3/4 of maximum. You should not hear anything
at this point. If you are hearing music, go back to
step #2 … if you are hearing voices, go see a doctor!

5) Now adjust the output level control until the “2
volt” or “5 volt” light starts to flicker. You will
want the output voltage to match up your ampli­fiers input gain levels. If you don’t know how
much this is, ASK the amplifier manufacturer or
read the owner’s manual of the amplifier.

6) Very Important - Set the input gains on the
amplifier(s) at minimum!

7) Double check that you performed Step #6

8) Decrease the volume control on your source
unit and re-connect the RCA’s between the DQX
and the amplifier(s).

9) Now increase the volume on your source unit
to your normal listening level. For some of you,
this may be louder than others!

10) At this point you may find yourself going back
and adjusting the “Output Level” controls on your
DQX to accommodate for the speaker placement
and efficiency.

4) Starting with the DQX “Input Level” control,
increase or decrease the control knob until the
“Input Maximized” LED begins to flicker steadily
with the music.

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AudioControl®

DQX Menu Screens

One of the major benefits of using Digital technol­ogy is the ability to use less knobs and buttons
and get more control. The DQX has two mono
equalizers, two parametric equalizers, plus a 3 ­way electronic crossover that would normally
occupy an area as large as your trunk. Yet digital
technology allows the DQX to offer a plethora of
features in one compact chassis. In addition there
are only a few knobs so navigating through the
DQX’s functions is quite simple.

When you first apply power to your DQX, it will
go through a few “wake-up” screens, including
some subliminal advertising for AudioCon­trol. It will then display a friendly
blue screen (not the scary blue
screen found on many computers).
Fear not, because the blue screen on
the DQX is actually a good thing.

Once your DQX has settled on one of
these menu screens, you will want
to spend a few minutes familiariz­ing yourself with the various
modes.

1) Digital Status Display - This cool blue
screen will tell you which mode your DQX is in.

2) Select - Every time you tap this button, you
will change the various modes in your DQX.

3) “+” and “-” Navigation Buttons: Depend­ing upon where your cursor is flashing, these
buttons will allow you to change a frequency,
apply boost and/or vary the bandwidth of your
equalization filters.

4) Left and Right Navigation Buttons:

Within each mode there are several sub functions
(i.e. Freq, Lvl, Crossover points, etc.) that you can
access using these buttons. By tapping on these

buttons and watching the flashing cursor,

you can navigate through each

function on the screen.

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Figure 6: DQX main menu screen

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MODE: Graphic EQ

Graphic EQ Freq = 1kHzGraphic EQ Freq = 1kHz

Graphic EQ Freq = 1kHz

Graphic EQ Freq = 1kHzGraphic EQ Freq = 1kHz
L= +6dB L= +6dB

L= +6dB

L= +6dB L= +6dB

Figure 7: Graphic EQ screen

Your DQX has 30 built-in graphic equalization
filters with fixed, constant-Q center frequencies.
These frequencies happen to match those on the
AudioControl SA-3055 real time analyzer. In the
Graphic EQ mode, you can select any of the 30
frequencies, one at a time, and apply boost or cut.
In addition you select whether you want the
equalization controls to affect the left and right
channels individually or control both channels at
the same time.

Freq(uency): This corner of the screen indicates
which frequency you are boosting or cutting. If
you wish to select another frequency, tap the left
or right arrow buttons until the cursor is flashing
on the number next to “Freq=”. Then use the “+”
and “-” controls to select the frequency you wish
to apply boost or cut.

>o<>o<

>o<

>o<>o<

R =+4dB R =+4dB

R =+4dB

R =+4dB R =+4dB

Stereo or Mono Equalization: After you have
selected a frequency to equalize, you must decide
whether you wish to equalize the left channel, the
right channel, or both channels simultaneously. If
you are a first time user, we suggest you equalize
both channels together at first and then individu­ally. Use the arrow keys to move the cursor to one
of the following positions:

“L=” Equalizing on the left channel
“>o<” Equalizing both channels simultaneously
“R=” Equalizing on the right channel

When the cursor highlights this screen, you can
now apply boost or cut, using the + and - controls,
to the frequency you selected in the previous step.

Once you have made your equalization settings,
you will want to tap the Select button, go to the
Memories screen, and save your settings in one of
the eight memory locations.

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MODE: Para EQ1 and Para EQ2

Para EQ1Para EQ1

Para EQ1

Para EQ1Para EQ1
Width=1/6Width=1/6

Width=1/6

Width=1/6Width=1/6

Figure 8: Para EQ1 screen

Para EQ2Para EQ2

Para EQ2

Para EQ2Para EQ2
Width=4 octWidth=4 oct

Width=4 oct

Width=4 octWidth=4 oct

Figure 9: Para EQ2 screen

Besides having a 30-band graphic equalizer, your
DQX also has two fully-programmable parametric
bands. These allow you to select a frequency,
apply boost or cut, and change the bandwidth or
“Q” of the filter.

Para EQ1 mode allows you set the controls for
one of the parametric bands.

Para EQ2 mode lets you change the settings for
the second parametric bands.

Freq=3.15kFreq=3.15k

Freq=3.15k

Freq=3.15kFreq=3.15k

LVL=+12dBLVL=+12dB

LVL=+12dB

LVL=+12dBLVL=+12dB

Freq=3.15kFreq=3.15k

Freq=3.15k

Freq=3.15kFreq=3.15k

LVL=0dBLVL=0dB

LVL=0dB

LVL=0dBLVL=0dB

Freq(uency): This corner of the screen indicates
which frequency you are boosting or cutting. If
you wish to select another frequency, tap the left
or right arrow buttons until the cursor is flashing
on the number next to “Freq=”. Then use the “+”
and “-” controls to select the frequency to which
you wish to apply boost or cut.

Lvl: When the cursor highlights this part of the
screen, you can now apply boost or cut to both
channels using the “+” and “-” controls. Please
note that you do not have individual channel
control using the parametric equalizers.

Width: This control lets you select how wide of
an area each of the DQX’s parametric bands
affects. You can choose a real narrow bandwidth,

th

1

like

⁄12

of an octave or go as wide as three full

octaves.

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MODE : Xover

XoverXover

Xover

XoverXover
PFM=30 Lo/Mid=90PFM=30 Lo/Mid=90

PFM=30 Lo/Mid=90

PFM=30 Lo/Mid=90PFM=30 Lo/Mid=90

Figure 10: Xover screen

In the Xover mode, the display shows the current
crossover and subsonic filter frequency settings.
These are the points where the subwoofer output
begins, where the subwoofer/midrange meet and
where the midrange/highpass outputs crossover.
Using the “Left” and “Right” arrows you can scroll
between the settings below. Then use the up and
down buttons to adjust.

PFM - The Programmable Frequency Match
(PFM) is a high pass filter that serves as a 24 dB/
octave subsonic filter for your system. Typically
you will want to set this at the absolute bottom
end or tuning frequency of your system

Mid/Hi=3.55kMid/Hi=3.55k

Mid/Hi=3.55k

Mid/Hi=3.55kMid/Hi=3.55k

Lo/Mid - This is the point where your
subwoofer rolls off and your midbass or midrange
speakers begin to play.

Mid/Hi - This is a low pass filter that selects the
setting where your high output begins to play.

MODE : Memories

MemoriesMemories

Memories

MemoriesMemories

Figure 11: Memory recall screen

This screen allows you to save or recall settings
from or to one of the eight memory locations.
Using the Left and Right arrows will cause the
cursor to highlight one of the following func­tions:

Recall: When the cursor is flashing next to this
word, you have the ability to recall one of the
eight memories. Push the “+” or “-” buttons to
scroll through the memories. All of the equaliza­tion and crossover settings are stored in each
memory.

Recall#7Recall#7

Recall#7

Recall#7Recall#7
SaveSave

Save

SaveSave

Figure 10: Crossover Response Curve

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AudioControl®

MemoriesMemories

Memories

MemoriesMemories
N (-) Y(+)N (-) Y(+)

N (-) Y(+)

N (-) Y(+)N (-) Y(+)

Figure 12: Memory save screen

Save: Once you have made your equalization

and crossover settings, you will want to save them
in of the eight memory locations. When the
cursor is flashing next to the word “Save”, use the
“+” or “-” buttons to select a memory location.
Once you have selected a memory location, tap
either the “Left” or “Right” button and the cursor
will move to the bottom left of the screen be­tween “N(-)” and “Y(+)”. Tap the (+) button to
complete the saving process or tap (-) to quit.

RecallRecall

Recall

RecallRecall
Save #5Save #5

Save #5

Save #5Save #5

MODE: Display

DisplayDisplay

Display

DisplayDisplay
BrightBright

Bright

BrightBright

Figure 13: Display brightness screen

In this mode, you have the ability to change the
brightness levels on the display of your DQX.
Using the left and right navigation buttons you
can toggle back and forth between “Bright” and
“Dim”. Once you have selected a brightness level
you are comfortable with, tap the “Select” button
and your last brightness setting will be retained.

DimDim

Dim

DimDim

ADJUSTING THE EQUALIZER

When it comes to music, everyone has their own
particular taste. Some people want pounding bass
and crisp, blood curdling highs. Others may prefer
a “flat” response (whatever the heck that is). At
the end of the day, most people just want their
system to sound balanced, “just like it did in the
store” or their buddy’s car. The following equal­ization guidelines should help you achieve your
own personal audio nirvana.

1) For optimum performance, get your hands on a
test compact disc that contains pink noise and a
good quality RTA (real time analyzer); we happen
to know someone who makes a really good one.
If you cannot locate an RTA, you probably want
to have your authorized AudioControl dealer
perform the equalization adjustments, as they will
likely have an analyzer. You can certainly adjust
your DQX using your ears, however an RTA will
give you the best results.

2) Begin playing pink noise through your system
and place the microphone for your analyzer on a
microphone stand in the driver’s seat. Take a
careful look at the “curve” on your analyzer and
how one frequency combines with the next.

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There is no one curve that will satisfy every
person, as we all have different tastes. How else can
you explain Liberace or rice cakes? The key is to
use your DQX to help balance your system from
one frequency to the next and give your speakers
the sparkle, sizzle, detail or punch that the acous­tics of the car have compromised.

3) Start equalizing by removing any large bumps,
peaks, or areas with too much energy at a particu­lar frequency. Next, boost the ranges that do not
have enough energy. We strongly recommend
that you cut or decrease energy before you boost.
Try to keep any boosts to +6dB or less for best
performance.

4) Although the plethora of controls on your DQX
can be intimidating, fear not they were designed
to give enough control to maximize your systems
performance but not enough to get you in
trouble. Here is an explanation of the key areas
you should focus on:

Sub-bass: 100 Hz and below - A car without
bass is like a day without sunshine…unless you
live where we do because most of the days in the
Pacific Northwest do not have sunshine. Bass is
one of the more critical areas although it is also
one of the most difficult to properly reproduce.
Most people prefer their bass frequencies to be 6 to
9 dB louder than the rest of their system, although

Figure 14: Sample RTA curve

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17

AudioControl®

there are some crazy folks that prefer their bass
substantially louder. The key in this area is to
have enough speakers and power to produce the
amount bass you desire but don’t use the controls
on the DQX to try and force your speakers to
produce sounds they can’t. Too much bass boost
creates a condition called “speakerus explodus”,
which is not pretty to hear or watch.

Midbass: 100 Hz to 300Hz - The phrase, “too
much of a good thing” can certainly apply to the
midbass frequencies. This is the transition area of
the audio spectrum that is an octave above your
sub-bass frequencies and several octaves below
your midrange. Most autosound systems have too
much mid-bass due to the fact that speakers
mounted in the doors or kick panels cause
resonance’s or peaks in the response curve. These
peaks in the mid-bass can actually mask or block
sounds in the all-important midrange area causing
your system to sound dull and lifeless.

Midrange: 300Hz to 3kHz - Musical instru­ments, vocals, mid-range percussion and many
things we associate with imaging and staging
happen in this area of the bandwidth. For that
reason you will want to keep this area as smooth
and balanced as possible. Too much boosting can
make you feel like you are listening to your sys-

tem in a tile bathroom. Not enough energy in the
midrange sounds empty and dry.

Treble: 3KHz and Up - If midrange is the cake,
then these high or upper frequencies are the frost­ing. Many autosound systems start a gradual decline
in this area which is why speaker placement is very
important. The DQX only gives you a few controls
in this area because too much boosting can really
make a speaker sound unnatural.

TROUBLESHOOTING

No Power: If the Power LED on your DQX will

not turn on, check to make sure that the power
wire and remote turn-on wires are connected or a
fuse has not blown.

System Sounds Unbalanced: Check your
graphic and parametric equalization settings to
make sure that one channel is not dramatically
different than another.

Sounds Distorted: Should your system sound
distorted or your speakers are moving way too
much, you should make sure you have your levels
matched properly and that your amplifier gains
are set at minimum. If this checks out okay, you
will want to look at your EQ controls to insure
that your boost levels are not overly boosted.

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Still Sounds Distorted: Look at the frequen­cies that you have selected for Para EQ 1 and Para
EQ 2 and see how much boost or cut you have
applied. Then look at those same frequencies on
your Graphic EQ. If you have boost applied to the
same frequencies on both types of equalizers,
there is a strong chance you are overdriving your
speakers and amplifiers at that frequency.

Output Voltage LED’s Don’t Light Up:

If your system is playing music but none of the
output LED’s are on, there is a good chance that
the output voltage of your source unit is not that
strong. Now before you call us and say, “The guy
at the store said my radio has high-voltage out­put”, you might want to face the fact that there is
“Engineering Voltage” and there is “Marketing
Voltage”. Without picking on any particular
source unit, remember that you do get what you
pay for.

UNDER THE COVER

1) Input Grounding: For most systems you

can leave this jumper set in the BALANCED
position. In some systems, the source unit may
look for a ground through the RCA connection to
the amplifier and create a ground loop, which in
turn can cause a whine (not the type that comes
in a bottle) in your system. In that event, you

Owner’s Enjoyment Manual

should go ahead and change the four jumpers to
the UNBALANCED position.

2) Ground Isolation Selector: Occasionally
alternator noise may appear in a system because
the source unit and amplifier are using different
grounding schemes. To help in this situation, we
have provided alternative grounding connections.
Make sure your system is turned OFF before you
move these jumpers.

Shipped Options

Input
Grounding Balanced Unbalanced

Ground
Isolation Isolated 200 ohms or Ground

Choice of
beverage Micro-brew Latté

Ë

Ê

Figure 15:
Inside of DQX

19

AudioControl®

IF YOU LIKE DQX, YOU’LL
LOVE…

The FOUR.1i is the perfect in-dash equalizer for
those of you who like the sound and detail of the
DQX but want to have some control of your
system from the dash of your car. Of course you
should not be driving while tweaking your
FOUR.1i, but enjoy it nevertheless.

AudioControl’s Four.1

And now a word from the legal department…

THE WARRANTY

People are scared of warranties. Lots of fine print.
Months of waiting around. Well, fear no more,
this warranty is designed to make you rave about
us to your friends. It’s a warranty that looks out
for you and helps you resist the temptation to
have your friend, “...who’s good with electronics”,
try to repair your AudioControl product. So go
ahead, read this warranty, and then take a few
days to enjoy your DQX before sending in the
warranty card and comments.

“Conditional” doesn’t mean anything ominous.
The Federal Trade Commission tells all manufac­turers to use the term to indicate that certain
conditions have to be met before they’ll honor
the warranty. If you meet all of these conditions,
we will warrant all materials and workmanship
on your DQX for one year from the date you
bought it (five years if it is installed by an autho­rized United States AudioControl dealer). We will
fix or replace it, at our option, during that time.

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Here are the conditional conditions:

1. You have to fill out the warranty card and send
it to us within 15 days after purchasing your DQX.

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2. You must keep your sales receipt for proof of
purchase showing when and from whom the unit
was bought. We’re not the only ones who require
this, so it’s a good habit to get into with any major
purchase.

3. Your DQX must have originally been purchased
from an authorized AudioControl dealer. You do
not have to be the original owner, but you do
need a copy of the original sales slip.

4. You cannot let anybody who isn’t (A) the
AudioControl factory; (B) somebody authorized
in writing by AudioControl to service your DQX.
If anyone other than (A) or (B) messes with your
DQX, that voids your warranty.

5. The warranty is also void if the serial number is
altered or removed, or if your DQX has been used
improperly. Now that sounds like a big loophole,
but here is all we mean by it.

Unwarranted abuse is (A) physical damage (don’t
use the DQX for a jack stand); (B) improper con­nections (120 volts into the power jack can fry the
poor thing); (C) sadistic things. This is the best
mobile product we know how to build, but if you
mount it to the front bumper of your car, some­thing will go wrong.

6. If an authorized United States AudioControl
dealer installs your DQX, the warranty is five
years; otherwise the warranty is one year.

Assuming you conform to 1 through 6, and it
really isn’t all that hard to do, we get the option of
fixing your old unit or replacing it with a new
one.

LEGALESE SECTION

This is the only warranty given by AudioControl.
This warranty gives you specific legal rights that
vary from state to state. Promises of how well the
DQX will perform are not implied by this war­ranty. Other than what we have covered in this
warranty, we have no obligation, express or im­plied. Also, we will not be obligated for direct or
indirect consequential damage to your system
caused by hooking up the DQX.

Failure to send in a properly completed warranty
card negates any service claims.

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21

AudioControl®

DQX SPECIFICATIONS

All specifications are measured at 14.4 VDC (standard automotive voltage). As
technology advances, AudioControl reserves the right to continuously
change our specifications…like our weather.

Maximum input level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.5 Vrms

Maximum output level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.5 Vrms

Output gain. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ± 10dB

Frequency response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Hz-22kHz

Total harmonic distortion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.01%

Signal to Noise ratio. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 105dB

Balanced input noise rejection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60dB

Input Impedance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20k Ohms

Output Impedance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150 Ohms

Crossover slope. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 dB/octave

Crossover type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-Way Linkwitz-Riley

Crossover frequencies . . . . . . . . . . . . . . . . . . . . . . . . . . . 110 steps in

PFM subsonic filter slope. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 dB/octave

Graphic Equalization Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 bands, 25 Hz - 20 kHz

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ISO 1⁄3 octave centers

Parametric Equalization Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 bands, 25 Hz - 20 kHz

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Adjustable Centers

Parametric Equalization Bandwidth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.08 to 3 octaves

Equalization boost/cut . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ± 12 dB

Power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . High headroom PWM switching

Power draw . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 600mA

Recommended fuse rating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Amp

Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.25" W x 9.9"D x 7"H

Weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.5 lbs

Country of origin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . U.S.A.

1

th

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©2003, AudioControl, a division of Electronic Engineering and

AudioControl, Making Good Stereo Sound Better, DQX, DQT,

and DXS, are all trademarks of Electronic Engineering and

This manual was conceived, designed, and written on several bleak,

windy, and dreary rain-drenched days at our home in the Pacific

Northwest Rainforest outside of Seattle, Washington. The lattés

were hot and the Heffeweizen’s were cold…like our weather.

Owner’s Enjoyment Manual

Manufacturing, Inc. All rights reserved

Manufacturing, Inc.

®

22410 70th Avenue West

Mountlake Terrace, WA 98043 USA

Phone: [phone]

Fax: [phone]

www.audiocontrol.com

The Strength of Digitaltm

AudioControl®

22410 70th Avenue West

Mountlake Terrace, WA 98043 USA

Phone: [phone]

Fax: [phone]

www.audiocontrol.com

The Strength of Digital

Owner’s Enjoyment Manual

®

P/N 9130690