Audio Control ESP-3 Quick start guide

ESP·3,.
IMAGE AMPLIFIER
OWNER'S INSTALLATION MANUAL
Congratulations on buying a truly unique enhancement to any quality car
stereo system. Properly installed and adjusted the ESP-3 will make an incredible
improvement in stereo imaging, ambience and sound stage width. However, right
up front
we strongly recommend that it be installed by a professional. Still, it
doesn't hurt to read this whole manual. It will give you an idea
of what has been
added to your system, how the ESP -3 works and a lot of other nifty stuff that will
make you the envy
of your friends (Imagine dropping little tidbits about opto-iso-
lated power supplies and psychoacoustic ear-brain processing).
Because this manual should most appropriately be used by a pro, we have
included a CO:rvtPRESSED POWER-USERS' HOOK-UP section. After all, you
want your system back as soon as possible -and installers often DO charge by the
hour....
Butread on anyway. Ther
e's nothing but re-runs on the tube.
WHAT YOU CAN EXPECT FROM YOUR AUDIO CONTROL ESP-3
• Serious, cast-in-stone, dead nuts imaging. Vocals come out of the
center where they're supposed to. Instruments are absolutely welded into
the stereo sound field, spread in a semi-circle in front
of you in a precise
array just the way they were when the song was recorded.
• The sensation of a larger space and wider sound field -far wider
than the physical dimensions
of your vehicle.
• Ease of control with a single unobtrusive dashboard adjustment (while
the rest
of the ESP-3 is mounted out of sight).
• Highest quality because the ESP-? is designed and built in the U.S.A. by
an award-winning manufacturer.
• Jealous friends, after they hear your car system.
Audio control ®
making good stereo sound better
22410 70th Ave West· Mountlake Terrace, WA 98043
Phone [phone] • Fax [phone]
1

Click here for full diagram >

SERIOUS CONSIDERATIONS •
EVEN FOR POWER INSTALLERS
•You MUST have a special center channel speaker with its own amplification
(otherwi
se you shoulda bought our ESP-2).
• The center channel speaker should be:
-as large as possible (not justa tweeter)
-placed as up front as possible (don't stick it down by th e gas pedal)
-sonically similar to the front left/right main speakers (more on all three
of th ese subject later).
•Your system should have good1rebleoutput. Themostoptimal set-up is separate
tweeters mounted relatively
hi gh in th e front passenger area: for example, at the top
of thedoor panels or on thedashboard. If you just have two6 "coax ialsplaying at your
pant legs
out of the kick plates at the bottom of yourdoors, theESP-3 wo n 't do its job
as dramatically.
• You need a good STEREO sound source. Lots of tape hi ss or multipath-
ridden
FM will frankly be exaggerated by th e ESP-3 's circuitry. And it can't take a
tape with very little stereo separation and work wonders on it.
Th e ESP-3 is pr etty
amazing but
it's nota miracle worke r.
:er Channel Amp -
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4-channel Amp
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Coax Speakers

GETTING TO KNOW YOUR ESP·3
Well, maybe notpersonally. Buton a first-name basis, anyway.
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The ESP-3 Main Chassis. The first thing you notice is that there aren't many controls
on the ESP-3 Main Chassis; just some set-and- leave-it Spatial Restoration tone controls
and a center channel gain control. That's because the main knobs are on the Dashboard
Image Control Unit.
Along one side of the Main Chassis, you'll see the Ground and +12 Volt terminals for
power, and a terminal for remote activation
of the ESP-3 when your head unit is turned on.
On the other side of the Main Chassis are:
1. Left & right INPUTS
2. Two OUTPUT CENTER connections (identical mono outputs)
3. Left & right "THRU" outputs -we'll explain this one later.
4. Left & right RESTORED OUTPUTS
5. A socket for the Dashboard Image Control's remote connection.
On the top surface of the ESP-3 are:
1. A power LED. It's handy for determining whether your power connections have
been made correctly or as a very dim reading lamp
if you like to hang out in your trunk.
2. BASS, MIDRANGE and TREBLE spatial restoration tone shaping adjustments.
3. CENTER LEVEL MATCH rotary gain control.
The Dashboard Image Control Unit. The control portion of the ESP-3 consists of
two rotary controls: a SPATIAL Enhancement Control and an Image Amplification control.
An LED tells you when the ESP-3 is operating. You must pull the Image Amplification
knob "OUT" to tum on the ESP-3 restoration circuitry.
The Image Amplification knob adjusts the focus on your stereo. The further to the
right, the sharper your center image becomes.
The SPATIAL Enhancement knob controls the restorative action of the ESP-3 's
circuitry. The farther to the right it is turned, the greater the effect of the ESP-3.
The best way to find the optimum settings for you and your system is to experiment.
4

HOW TO INSTALL THE AUDIO CONTROL ESP·3
Before we dig into this, we want to give Professional Installers another plug. They can
do a great job of installing the ESP-3 and yournew center channel speaker. We're just
pointing out that installers have a lot of experience and exactly the right tools.
In addition, the ESP-3 includes a third channel. Determining the right kind of speaker,
power amplifier and level match with left and right main front channels is best done with
the benefit
of some experience -not to mention a professional spectrum analyzer such as
the AudioControl Industrial SA-3050A.
That said, we'll proceed to ...
A. THE MOST IMPORTANT I NSTRUCTION OF ALL
Fill out the WARRANTY CARD and mail it in!
It's also critical that you keep your invoice or sales slip
to establish the
date when you purchased your ESP-3,
and hence your warranty. It's also good insurance
proof should a car thief take a fancy to your system.
Insurance companies are notably reluctant to believe
something
as esoteric as the ESP-3 was part of a
system.
B. PLACEMENT AND MOUNTING OF THE ESP-3 MAIN UNIT
Placement. Theoretically, you can place the ESP-3 anywhere that it can receive
power.
The most convenient places are under the dash, under the seats or in the trunk.
While the ESP-3 has been designed with very rugged parts, and engineered in a manner
which reduces physical circuit board stress, be sure to consider the following guidelines:
Avoid mounting the ESP-3
near a heater, in front of the firewall or anywhere else
where it can get really hot.
The mounting location must be safe from water seepage. Lots of trunks have seal prob-
lems (poor gaskets,
not sleek, furry mammals who balance beachballs and eat mackerel at
the zoo). Check for old water stains.
Make sure the ESP-3 can be firmly mounted without vibration. This protects connec-
tions from breakage and stress as well as the possibility
of it coming UN-attached when you
blast over a speed bump.
Avoid any location where mounting screws may potentially pierce a gas tank (lots
of
which are in the vicinity of the trunk) or gas, brake or electrical lines.
Mounting. The ESP-3 installs just like a power amplifier, secured by four screws and
lock washers through the four slots in the unit's base.
1. First place the ESP-3 in its mounting position and mark the four screw holes. Try
to keep them to the outsides of the slots if possible.
2. Now remove the ESP-3 and drill four small pilot holes. This will insure accuracy
and guard against stripping out the larger holes to come.
3. Drill the larger holes.
4. Replace the ESP-3 and secure tightly with four sheetmetal screws and lock washers.
5

C. PlACEMENT AND MO U NTIONG OF THE ESP-3 IMAGE CONTROL
The Image Control may be mounted under the dash using its own bracket or through
the dash without the bracket. It should be within reach of the driver and where the indicator
LED is plainly visible.
Under-d
as h In sta ll ation. TheImage Control mounts with four screws which attach to the
underside
of the dashboard. Since you 're going to need to slide in upside down to get a clear
view
of the nether parts of the dash, it's handy to have a Faithful Assistant to hand you things.
1. First slide into the car and place the Image Control in
its potential mounting
position (this is starting to sound kinky). Now ask for "Forceps" and then tell your assistant
you're just kidding and want the pencil instead.
2. Mark the four holes and remove the Image Control.
3. Drill four holes into the dashboard underside.
4. Replace the Control and secure it with four screws.
In-Dash
In sta ll ation. For that custom, finished look (or if under-dash mounting just
isn't practical), the Image Control can be mounted directly into the dashboard.
We have
provided an extra label and LED holder
to make this easier. A small hex driver, medium
screwdriver, pliers, and power drill with 9/32", 13/64" and 1/8" bits are required
... along
with some patience and delicacy.
1. You will need to disassemble the ESP-3 Image Control. First gently pull the LED
assembly from its black plastic holder on the Image Control bracket. Do not remove the
actual LED wires from its connector, if possible.
2. Next, remove the circuit board and rotary controls from the bracket. Take off the
knobs by loosening their set screws, then unscrew the lock nuts and washers.
3. Now take a deep breath and using the label
as a template, drill two 9!32" holes in
the dashbOard
(if this is a burlwood Rolls Royce dash, you 're a very gutsy person).
4. Drill 1/8" holes for the lock tabs. Or remove the lock tabs if you're sure you can
keep the circuit board from rotating.
5. Drill a 13/64" hole for the LED.
6. Apply the pressure-sensitive label.
7. Remove the black plastic LED holder from the Image Control bracket and push it
into the 13/64" hole.
8. Insert the rotary control/circuit board into the 9/32" hole, and the LED assembly
into its black plastic holder. Make certain the red wire on the connector goes to the long
lead
of the LED.
9. Checkfor any parts ofthe LED wires orcircuitboard touching metal and then replace
the lock nuts and washers and tighten securely.
6

10. Finally, put the knobs back on and tighten the set screws.
11. Enjoy the applause and
go buy your Fearless Assistant a beer, Pepsi, Yoohoo or
diet Ginseng soda.
D. ESP-3 AUDIO WIRING
Center Channel Speaker Considerations. Key to the ESP-3's Image Amplification
process is an additional center channel speaker. Your choice
of speaker should be a
function
of the following considerations (does that sound official or what?). It should be:
•In the center. This may sound like we're stating the obvious, but the center channel
MUST be placed in between the left and right front speakers. It "anchors" the stereo image
and
if you skew center channel to either side, the whole gigantic Spatially Restored, Image
Amplified sound will be out
of whack.
• As large as possible. Center channel information is definitely FULL range. So,
within reason, you should use a full-range center speaker. The absolute smallest would be a
4 incher (some claim
to go down to 90 Hz but we don't believe it). 5-inch or 6x9 coaxial is
far better. We've made things easier by including a PFM filter which acts as a low-cut
filter, but the speaker should be capable
of strong output right down to the cut-off fre-
quency. We said "largest within reason" because another factor enters in. ..
• Placed as up front as possible. Because the center channel is full range it contains
treble which doesn't fare too well
if its playing at the listeners' knees. Obviously larger
speakers are harder
to mount high up in the center.
• Finally, the speaker should have the same sonic signature as the left and right
speakers.
In other words, its frequency response should resemble that of the main speakers.
If you have carbon fiber tri-axials with titanium tweeters on the sides, don't use a cheap,.
mushy cardboard cone "full range" in the center -it won't have the same mid and high
response.
If you have separate mid/woofers and tweeters on the sides, consider *e same for
the center
if there's room.
Amplifier Considerations. The ESP-3 creates the need for an extra amplifier charmel.
If you had two before you'll need three. If you're running the ESP-3 with a really compli-
cated multi-amp system, we'll leave you to your own mad-scientist plans. But if the ESP-3
is part of a smaller system (one with just front left, front right and subwoofer, for example)
you might consider taking advantage
of a 4-channel amp. If the .lfVOOfe r isn't too big, you
can run left, right, center and subwoofer offone channel each. The other option is
of course
to devote a whole amp to the center channel. If this is the case, just size it so it is driven by
about the same power as the left and right front channels. For example,
if the left and right
speakers are being driven by 50 watts, select a 50 watt amp.
Or use a 25-watt amp and
bridge it.
The ESP-3's THRU Connections. Along with the regular INPUT's and OUTPUT's,
there are left and right THRU sockets. These are really two more OUTPUT's except that
the ESP-3's circuitry doesn't affect their sound. This is so you can drive other sets
of
speakers where you don't want the spatial restoration effect without resorting to "Y" cords.
Center Channel Outputs. They're both the same output and are mono, so don't
entertain ideas about trying to get a stereo center channel or anything like that. We
provided two to give you additional flexibility in sophisticated, multi-channel installations
like the example below.
Planning Your Hook-up Strategy. Okay, time to trot out the flow charts and
diagrams. Naturally, there are lotsa ways
to hook up the ESP-3, depending on what the rest
of your system is like and whether you choose to use the THRU connections.
7

The simplest type of system is one where you're adding the ESP -3 to a system with a
tape deck and a single stereo power amplifier.
In this case, the ESP-3 goes between the tape
deck and the amplifier.
One connection is made between an OUTPUT CENTER socket and
another amplifier or amp channel. Its output
is hooked to the center channel speaker. If
you're also installing 1be Epicenter, it should come BEFORE the ESP -3 in the signal path.
Any equalizer
or crossover should be AFTER the ESP-3.
0
R emo i ts
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Simple Stereo System with The ESP·3 and The Epicenter
A simple bi-amp system splits the full-range output of your deck into high and low fre-
quencybandsand then routes them
to separateamps. Becausethe ESP-3 works across the whole
sound spectrum, it should
be connected BEFORE the inputs of the electronic crossover.
0 Cenrt r
Pl : uc
Remote
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Spto:1kcrs
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Pla1e ·
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Spc:ike rs
Sub Woofor
The ESP·3 with an Equalizer and an Electronic Crossover
8

Here's an example using the 4XS where the ESP-3's THRU outputs are also used:
Re mo re
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He ~ Unit wi.1h only
One hc:.J.mp Ou tp uc
Center
Ou1
Sub Out
•4 <"hanMI ( f'OSSOVCf
wilh non·hdi .ng bus
Sub Woofer
Amp
(Adju st F' ronMo-reu Balance wi th 4XS
Output Ga in Conrrols)
Using the ESP·3's Thru Outputs
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nter
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Pbte
Spc.akcr
0 Fro
nt Side
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s~~lccrs
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Rea1 Side
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Spo k en
Sub woorer
We know you've probably dreamed up others which makes this look primitive so we'll
give up. Like Carl Sagan used to say, "There are billions and billions of possibilities."
Type of Wire . It is extremely important to use high quality coaxial stereo hook -up
cables for the audio signal wiring. Intense electromagnetic fields are generated
in an
automobile which can be picked up by car stereo wiring. Theoretically, all RCA -type coax
cables (like the ones
you use to hook up your home stereo) are shielded to prevent interfer-
ence. Unfortunately, cheapoid cables skimp
on external shielding, because interference is
not a problem in most home hi-fi hook-ups. Avoid the temptation to simply use "that old
set
of patch cords that came with my receiver".
Consult with your Audio Control dealer to obtain high quality, well-shielded cables
with securely fitting connectors
on each end. Remember, it's better to invest in good cables
before installation, rather than
try to trace noise once inferior cables are buried in your car's
interior.
Audio Wiring Placement. We recommend that you route line level (coaxial) wiring
between the head unit and the
ESP -3 away from car wiring, amplifier power cables or
speaker wires. This will help avoid noise induction problems, especially when you're
running cables from the head unit all the way back to the trunk.
The one exception to these precautions is the remote wire between the ESP-3 main unit
and the remote Image Control.
It only carries control voltages, not an audio signal and is
not prone to interference. Just make sure it doesn't rub against anything or is otherwise
violated along the way.
Audio Connect io ns. After all this preface, there really isn't much to say. The signal
from the
head unit goes into the INPUT sockets on the ESP- 3. Outputs to the equalizer take
off of the OUTPUTS. One or more feeds for the center channel exit the OUTPUT CENTER
sockets.
Make sure these connections are really snug.
If you need another set of full-range outputs for speakers like subwoofers or rear satel-
lites where
you don't want ambient effects, use the THRU output sockets.
9

E. ESP·3 POWER WIR I NG
IMPORTANT: Disconnect the negative terminal of your car's battery before working
on any electrical connections. Unless you want a little extra tingle in your life.
Type of Wire. Both +12 and ground(-) connections to the ESP-3 should be made with
multi-stranded wire
no smaller th an 16 gauge.
The remote tum-on connection between power amp and the ESP-3 can be made with
thinner wire.
Positive (+12V) Connection.
If th e ESP-3 is being mounted near the power amp(s),
you may simply make a parallel connection from the amp's +12V terminal to the ESP-3's
+12V terminal. A fuse orcircuit breaker never is a bad idea. Use at least a amp rating.
Gro u nd Connection. The hook- up most open to interpretation and possible problems
is the ground connection. For best protection from noise, there should be ONE AND ONLY
ONE ground path to the negative side
of your vehicle's electrical system. That means
connecting the ground terminals
of the head unit, ESP-3, and power amplifiers together to
someplace you're SURE is actually part of the negative side of the car's electrical system;
preferably the battery itself. The nearest piece
of bare metal probably isn't a true ground.
If you're in doubt, connect the car stereo system's common ground directly to the battery's
negative terminal or where the battery's negative grounding strap contacts the vehicle
frame.
Remote Turn-on Connection. Sounds titillating doesn't it? Actually, what it means
is that the ESP-3 is turned on by a control signal from the head unit. Locate the remote
tum-on terminals on both the ESP-3 and one
of your power amplifiers or the head unit and
connect them.
Center Channel Connections. The really REALLY unique thing about the ESP-3 (as
compared
to our merely really unique ESP-2) is its center channel. I t's what makes the
ESP-3 a true "Image Amplifier". The center output is not just full range mono, but has
been processed via all sorts
of electronic wizardry in order to provide complimentary ef -
fects to the Left/Right SPA TI AL RESTORATION. Make sure to read our previous recom-
mendations as to type of center channel speaker, placement and other advice for living.
IMPORT ANT: The Prog ra mm ab le Frequency Match (PFM) Circuit. The ESP-3
has a special programmable circuit to prevent the center channel speaker from trying to
reproduce low frequencies.
If you're using, say a 5" center channel speaker, it can't very
well be expected
to crank out 40 Hz bass. Or at least it may cough out its voice coil trying.
That's where the PFM circuit comes in. You could think of it variously as a crossover
or a low cut filter (or just nifty
if you're not technically minded). When shipped from the
factory, the ESP-3's PFM is programmed to cut off frequencies below 150 Hz (for the
center channel only). That should protect even the lamest 5-inch speaker.
If you're used
to installing other Audio Control Performance Match Components such as our 4XS, and
desire a higher or lower frequency, you'll know what to do.
If you don't, you should take
the whole thing to a professional installer.
The wrong PFM frequency could damage the
center channel speaker or at least cause intermodulation distortion.
F. A SHORT TEST RUN
1. First, re-connect the negative terminal of the car's battery.
2. Next, make sure that any other dashboard equalizer.loudness or tone controls are
either switched out
of the signal chain, or turned to their center (neutral position).
3. Confirm that the three rotary controls on the top
of the ESP- 3 (BASS,
MIDRANGE, TREBLE) are set in their center detent position.
4. Make sure that the CENTER LEVEL MATCH gain control is at i ts center detent
position. 10

5. Tum the ESP- 3's Spatial Restoration and Image Amplification Controls all the
way to the LEFT (7 o'clock position) and pull the Image Amplification knob out. The LED
on the remote should be on now.
6. Now pop in a tape or CD and tum the system
up to a pleasant listening level.
7. Do you hear silence instead
of sound? If so, check the wires from the head end
unit
to the ESP-3, or the ESP-3 to the power amplifier. Make sure the Power LED on the
main unit is on.
8. Make certain the Image Amplification knob is pulled out and turned to the left.
Now rotate the ESP-3 Spatial Restoration Control to the right (toward MAX).
Do you hear
wonderfully wide stereo with the sound actually wider than the confines
of the vehicle? If
so, the basic connections have been made correctly. If you hear sound, but nothing
different even though you've turned the Image Control all the way up, check all connections
including the one between the ESP-3 main chassis and the dashboard Control. Also check
that you pulled out the knob on the dash control.
If the LED is glowing brightly on the dash
control and you do not hear a difference, check to see
if you have used the THRU jacks by
mistake
9. Now check the center channel speaker. T um the Image Amplification knob to-
wards the right. Is sound coming out
of center speaker? If you're not getting any sound,
check the signal and speaker hook-ups, make sure the center channel power amplifier is on,
etc. Most likely, sound WILL be coming from the center channel. Adjust the CENTER
LEVEL
MA TCH control if it is too loud or too soft. Remember, we're just going for an
approximation.
SAGE ADVICE from the old Performance Matcher in the Sky: The first inclination is
to tum up the center channel too loud. Like the first time you get a subwoofer (either at
home or in a car), you crank it at a high, obvious level for a
few days and then realize that
you're overdoing it. Try to go for a level that BLENDS the center with left and right. Like
a subwoofer, it should be "there" but unobtrusive.
10. Now with the controls cranked back to the left (off) position, rotate the head unit's
balance control
to the far left. Does the sound in the car move to the left? If the sound
heads to the starboard (right for you landlubbers), the RIGIIT and LEFT inputs or outputs
need to be checked at the ESP-3 and power amp(s). General practice is to use RED plugs
for RIGHT and BLACK (or White) plugs for left. Make sure
Llfl' is LEFT all the way on
through from the head unit
to the power amplifier inputs. If the problem persists, tear your
seats out, tum them the other way and only drive your car in reyerse.
G. ADJUS T ING THE SPATIAL RESTORA T ION TONE SH AP I NG CONTROLS
On the top of the ESP-3 are three "tone" controls. NOTE: They only affect the spatial
restoration (ambience) effects added by the ESP-3, NOT the overall sound
OR the center
channel.
·MID, TREBLE and BASS ESP-3 controls really have two different purposes: First,
they can be used
to compensate for various speaker inStallations. If you have OK treble but
not as good as we've recommended, you can adjust the TREBLE EQ on the ESP-3 control
to boost the high-frequency ambient products.
If the ESP-3's effect is not pronounced
enough, kick up the MIDRANGE.
If your system is really bass-heavy and the ESP-3's
effect sounds weird through the subwoofers, reduce the BASS, etc. Second, the EQ controls
can be used purely to change the effect
of the ESP-3. In other words, use your own taste.
Go nuts!
11

To set these controls:
1. Play the same tape or CD you did before.
2. One
by one rotate each control all the way to the left and then all the way to the
right
to familiarize yourself with them. Make sure to return each control to the center
detent position before experimenting with the next one.
3. Adjust them the
way you think they sound best. This is purely subjective. If
you're still confused, here's a good starting point to try.
Bass Midrange Treble
C) 80
4. Now, try some different tapes or CD's or tune in a clear, strong FM station and
experiment with the ESP-3 Image control
to discover how much wider and more dramatic
stereo can be.
5. Get out of your car and call at least three friends with car stereo systems that
could benefit from
an ESP-3 and extensively brag to them about how much better your
system sounds.
H. ADJUSTING THE CENTER SPEAKER LEVEL .
The center speaker gain setting•on the master unit should be set so that the image
moves
to the center, but the overall total sound does not change.
To do this, set the Image Amplification knob all the way to the right and compare it in
and out. Adjust the center level gain
so as you click in and out, the overall sound doesn't
increase or decrease but the image moves solidly center.
Aga~. your taste is what is right.
The Autosound Police won't come
to your house.
GENEUL EXPLANATIONS, CONFIDENTIAL·TO·INSTALLERS AND
OTHER UNSOLICITED ADVICE
WHAT HAVE I BOUGHT? A DISCUSSION OF THE ESP·3'S TECHNOLOGY
The ESP-3 In Action: SPATIAL Restoration. What is SPATIAL restoration? Let's
start with the basics.
Obviously there IS a difference between stereo and mono.
It's the difference between
left and right channels. We call that
LEFr MINUS RIGHT (L-R). Sometimes the differ-
ences are obvious:
If a guitar sound seems to be placed to the left in the sound field, you
can bet there is more guitar in the left channel than the right. Not all
of it but MORE.
However, L-R has another purpose, too. It contains the SPATIAL cues which have
been captured during recording or synthesized at the srudio. This includes
the echoes and
reverberation which give you a sense
of space and position in relation to the performers. It
creates the spaciousness which sets stereo apart from mono.
12

The ESP-3 creates a copy of the L-R component of the input signal, amplifies it,
shapes its tonal contours and then injects it back into the main signal.
It's sort of like
adding "seasoning" to the "bland", normal sound. The amount
of additional L-R signal is
controlled by the remote Spatial Restoration knob on the dashboard.
The actual "flavor" of
the additional SPATIAL information is controlled by the three tone control knobs on the top
of the ESP-3.
The ESP-3 In Action: Image Amplification. The AudioControl center channel image
amplifier can dramatically improve the sound
of a car system. Our psychoacoustic ear-
brain processing system has to be fooled into combining left and right channels into a solid
"between the speakers" image. This same ear-brain processing system works best when the
speakers are (you guessed it) IN FRONT
of you. Like a home stereo system. Even if you
slather the dashboard with mini-tweeters, it is still not possible
to achieve the best imaging
configuration for fullrange sound (and hence full range imaging). An additional seasoning
of Left plus Right information projected from the center of the stereo sound stage psy-
choacoustically establishes a reference point.
We didn't invent the concept. People have been doing summed mono center channels
before this. But the problem here
is that all they get is TWICE as much mono information
(they're essentially getting L & R PLUS L+R). Even
if the speake r' s volume is reduced,
that still detracts from the sound field's width and spaciousness. The ESP-3 does it right by
electronically processing the L+R portions
of the signal and sending the right amount to
your center channel speaker. Yes, this circuitry is patent pending.
Nailing Hum. Yes, we're proud of how the ESP-3 can enhance the stereo effect in
your car and center the stereo image dead-on right there on top
of the Styrofoam rear view
mirror dice. But changing sound is one thing, making sure that adding extra "boxes" into
your signal chain doesn't also add noise is equally important. That's why we've added a
special optically-isolated switching power supply for superior noise rejection.
From an audio standpoint, car electrical systems are about
as quiet as a rock concert in
a motorcycle factory during an earthquake. (For a thorough discussion
of this, send for our
Technical Paper 103).
While the ESP-3 will not contribute to this electronic cacophony, it must be capable of
REJECTING everything thrown at it. It does this with a special switching power supply
like those used in computers and electronic test instrumentation. This power supply is
optically isolated to keep this trash away from
yo ur audio signal.
GETTING THE MOST FROM THE ESP·3
As we said in the quick introduction, certain factors affect the performance of the ESP-3.
These include:
• Correct center channel speaker type and placement. This is covered a while back but
is VERY important to the Image Amplification process.
• Correct adjustment of the center level match.
• Sufficient power. If a system is bogged down and on the verge of clipping, it cannot
successfully reproduce much L-R, much less an extra healthy dose from the ESP-3.
•Good treble and midrange speakers. The majority of L-R SPATIAL information lies
from about 500Hz on up. A muffled system with indistinct sound will get a little better
with the ESP-3 cranked up.
•A good STEREO sound source. Some tapes (due to crummy cassette decks with poor
separation) just don't have as much L-R information as they should have. Multipath-ridden
FM,
on the other hand, has TOO MUCH. The ESP-3 will grab the interference and
REALLY make it sound unpleasant. Itwill also do weird things to tape hiss.
13

I. FOR I NSTALLERS ONLY
Yes, we know that means everyone will immediately read it. But there's nothing
secret here.
Ground Loops. Ground loops are insidious. They are caused by the non-zero
resistance
of the wire used to interconnect the equipment. Typically, ground loops are
created by a piece
of equipment having multiple connections into the grounding system.
The drawing below shows what happens. Generally, the audio wiring has higher
resistance than the power wiring. Since the electrical system
of the car uses the body/frame
structure as
it's negative return, the non-zero (yes, it's small, but not small enough!)
resistance
of the car body allows small voltage drops to be created between various points
in the car body. Trunk
+12 Volts Firewall +12 Volts ; +12 Volts
1Battery
I
I
I
----------L
I
---------'-
J---v.,·.,--~ -- B-o-dy-Grou-nd _____ -r";"v'\,-f ~ :, --- --
Body Ground \ :I LQ)---J Body Ground
l Voltage Drop 1
Resistance
Between
2 Points
Caused
by
Current Flowing
Through Resistance
Ground Option Switch. All of the above would suggest that we want total isolation
between signal ground and power ground.
fu most cases you do. But occasionally (and
with certain brands
of head units and amps who will remain mentionless here), it is neces-
sary to actually reduce the amount of isolation which we worked and slaved and strived to
achieve with our optically isolated power supply.
fuside the ESP-3 (see why this is in the installers-only section?) is a 3-position slide
switch.
In position 1 (all the way to the LEFT), it provides total isolation -infinite ohms
with an optical isolator. fu the center position, you get 200 ohms
of isolation. In the
almost-never-used (except with
--oops we almost said that brand name) far RIGHT
position 3, the signal and power supply grounds are combined. Use the switch as a last
resort. Alternator whine can almost always be cured with proper grounding practices.
Sett ing the Pr ogramma ble Freq uency Match. This is covered in Tech Note 1004.
Ladies and Gentleman, do not try this at home. Also, we have a special Tech Note on
building modules. That is number 1006.
Setting Cen ter Channel Gain. We've given you some guidelines on achieving proper
center channel balance via the ESP-3's CENTER LEVEL MATCH CONTROL. But for
those
of you who really enjoy our glib prose, we've concocted a special Tech Note just on
this subject. Look for it on the best-seller list
as Tech Note 1005 -Adjusting Center
ChannelGain.
MISCELLANEOUS TROUBLESHOOTING NOTES
• The LEDon the dashboard Image Control wi ll not light ifthe cab le or LED wires are
shorted anywhere.
•The Control Knob won't do zip if the cable is sho rted, violated or partially discon-
nected.
14

•Make sure that the THRU connections haven't gotten mixed with the OUT P UT's -
you won't get any effect out of them.
• The ESP-3 won't amaze you and your friends unless you pull the knob out to tum it
on. •
The ESP-3 does not work with The Epicenter or ESP-2 dashboard remotes.
A BRAZEN PLUG FOR OTHER AudioControl PRODUCTS
The AudioControl ESP-3 is part of our PerformanceMatch Series which includes:
• The EQX, a compact, 2-channel, audi oph ile-grade, digital-
,-;:: .. . ' -=;:;9..~~,"' ~- ready 12-band equalizer, line level preamplifier, bridging adaptor
:a \ .t::J ••• • ~-- ~~ ~
,'.~(:;::.p.t:!-':}-•" ·:~~ ~ and programmable electronic crossover. Winner of the Autosound
· ~;d:'G;"2:~:"2·"'?.! · " • • Grand Prix Awards in 1987, 1989 and 1990).
~ - \ '' ~~ • The EQL, 12-band equalizer with input line preamplifier.
~. ~ Same ultra-handy 5-band half-octave bass equalizer and 7-band octave
stereo equalizer as the EQX. 1988 Equalizer
of the Year
•
The EQQ, a 4-channel version of the EQL.
•The EQT, an amazing TH IRD -OCTAVE mono equalizer that gives you the greatest
possible tonal control over the entire frequency range. Thirty (count'em)
30 separate bands
with Constant Q circuitry which minimizes adjacent band interaction. Yep, this one also
won a Grand Prix award!
• The 2XS, 2-way 18dB/octave programmable electronic crossover with 18dB/octave
subsonic filter, output gain adjustment and bridging adaptor.
•The 4XS. This is more than just a double 2XS. It is a 4-
channel 2-way or 2-channel 3-way crossover with non -fading
bass.
It allows up to five different frequency parameters to be ·~
customized for multi-speaker, multi-amp systems. If you 're into
serious sound, check this
one out.
•The ESP-2, the ES P -3's little brother. Left/Right SPATIAL Restoration, but not cen-
ter channel for Image Amplification.
Each
of th ese components will deliver significant improvements in the sound of any
car system and are part
of the AudioControl Performance Match system. Check with your
AudioControl dealer for the juicydetails.
AUDIO CONTROL ESP·3 SPECIFICATIONS
A ll specifications are at 14.4volts DC
Total Harmonic Distortion 0.
03%
Signal to Noise Ratio (full output) - llOdB
Input Impedance 20 KOhms
Output Impedance 150 Ohms
Maximum Output Level 7.5 volts
Frequency Response ±-0.5dB:lOHz -50KHz
Power Supply Transformer coupled, switching DC/DC converter with optical isolation
Current Draw (maximum)
500 mA
Size 1.20"H x 7"W x 5.6"D
Country of Origin U.S.A
15

AUDIO CONTROL ESP·3 LIMITED WARRANTY
People are scared of warranties. Lots of fme print. Lots of noncooperation. Well, don't
be scared of this warranty. It's designed to makeyou 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 withelectronics", try to repair your Audio Control ESP-3. So go ahead and read
through this warranty, then enjoy your new component for a few days before sending in the
warranty card and comments.
If you honor these conditions, we will warrant all materials and workmanship on your
ESP-3 for ONE YEAR from the date you bought it, and will fix or replace it, at our option,
during that time.
Here are the conditions that make this warranty conditional:
1. You have to fill 9ur the warranty card and send it to us within 15 days after you pur -
chased your ESP-
3.
2. You must keep your sales slip or receipt so you have proof when and from whom
you bought your ESP-3.
3. Your
ESP -3 has to have been originally purchased from an authoriz ed Audio Control
dealer.
4. You carmot let anybody
whci isn't; (a) The AudioControl Factory or (b) Someone au -
thorized
in writing by Audio Control to service your ESP- 3. If anyone other than (a) or (b)
messes with your ESP-3, that voids the warranty.
5. The warranty is also void if the serial number has been altered or removed, or if the
Audio Control ESP-3 is used improperly. Now that sounds like a big loophole, but here is
all we mean by it:
Unwarranted abuse is; (a) Physical damage (our mobile products are
not meant to
be used as jack stands for your car); (b) Improper connection. We have done the best we
can to protect the inputs, however, 120 volts into the jacks can fry the innards of the poor
beasty. (c) Sadistic things. This
is the best mobile product we know how to manufacture,
but if you use it on the front bumper of your Baja bug and get it full of water, things will go
wrong.
Assuming you conform to numbers 1-5, and it
isn't all that hard to do, we get the
option
of deciding whether to fix your old unit or replace it with a new one.
Legalese Section
This is the only warranty given by Audio Control. This warranty gives you specific
legal rights that vary from state to state. Promises
of how well your ESP-3 will work are not
implied by this warranty. Other than what we've covered in the warranty, we have no
obligation, express or implied. Also, we will not be obligated for direct or indirect damages to
your system caused by hooking up the Audio Control ESP-3. Failure to send in a properly
completed warranty cardnegates any service claims.
© 1990 AudioControl, All Rights Reserved, Audio Control, Making Good StereoSound Better, The
Epicenter, EQX, EQL, EQT, EQQ, ESP-2, ESP-3, 2XS, and 4XS are trademarks of the AudioControl
Division
of Electronic Engineering and Manufacturing, Inc.
Printed in the NorthwestRainforest on a special paper composed of recycled cedar bark coated with
banana slug emulsion.
making good stereo sound better
22410 70th Ave West • Moun
tl ake Terrace, WA 98043
Phone 206-775-
8461 • Fax [phone]
16
PN 794-06/

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Ba ss
Th ese sen in gs are a good starting point.
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----, Front
4-channel Amp
Front K
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