Directed Audio A404 User manual

models
A502
A404
OWNER’S
MANUAL

22
© 2004 Directed Electronics, Inc
TABLE OF CONTENTS
CONGRATULATIONS
Congratulations for choosing a Directed
Audio power amplifier from Directed
Electronics, the industry leader in high
quality automotive security and audio
equipment since 1990.
Directed Audio power amplifiers
continue to set new standards of perfor-
mance, reliability, and affordability in
the mobile electronics industry.
Featuring high-efficiency MOSFET power
supplies, flexible on-board crossovers,
and state of the art audio design,
Directed Audio power amplifiers will
excite and delight the mobile sound
enthusiast with years of high-quality
audio reproduction.
Directed Audio power amplifiers come
with a two-year limited warranty if
installed by an authorized Directed
dealer. If not installed by an authorized
dealer, Directed Audio power amplifiers
are covered by a one-year, parts-and-
labor limited warranty.
Be sure to retain your original sales
receipt and refer to the warranty section
of this guide for full details about your
coverage.
Limited two-year consumer warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Warning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Installation guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Front panel connections/controls A502-A404 . . . . . . . . . . . . . . . . . . . . . .7
Rear panel connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Speaker wiring diagrams A502 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Speaker wiring diagrams A404 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Crossover settings and gain adjustment . . . . . . . . . . . . . . . . . . . . . . . . . .14
LED Tube Installation (Optional) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
CEA Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17

LIMITED TWO-YEAR CONSUMER WARRANTY
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© 2004 Directed Electronics, Inc
Directed Electronics, Inc. promises to the
original purchaser, to replace this product
should it prove to be defective in workman-
ship or material under normal use, for a
period of two years from the date of
purchase by the dealer as indicated by the
date code marking of the product
PROVIDED the product was installed by an
authorized Directed dealer. During this two-
year period, there will be no charge for this
replacement PROVIDED the unit is returned
to Directed, shipping pre-paid. If the unit is
installed by anyone other than an autho-
rized Directed dealer, the warranty period
will be 1 year from the date of purchase by
the dealer as indicated by the date code
marking of the product. During this 1-year
period there will be no charge for this
replacement PROVIDED the unit is returned
to Directed, shipping pre-paid. This warranty
is non-transferable and does not apply to
any unit that has been modified or used in a
manner contrary to its intended purpose,
and does not cover damage to the unit
caused by installation or removal of the unit.
This warranty is void if the product has been
damaged by accident or unreasonable use,
neglect, improper service or other causes
not arising out of defects in materials or
construction. ALL WARRANTIES INCLUDING
BUT NOT LIMITED TO EXPRESS
WARRANTY, IMPLIED WARRANTY,
WARRANTY OF MERCHANTABILITY,
FITNESS FOR PARTICULAR PURPOSE, AND
WARRANTY OF NON-INFRINGEMENT OF
INTELLECTUAL PROPERTY ARE EXPRESSLY
EXCLUDED TO THE MAXIMUM EXTENT
ALLOWED BY LAW, AND DIRECTED
NEITHER ASSUMES NOR AUTHORIZES
ANY PERSON TO ASSUME FOR IT ANY
LIABILITY IN CONNECTION WITH THE
SALE OF THE PRODUCT. DIRECTED HAS
ABSOLUTELY NO LIABILITY FOR ANY AND
ALL ACTS OF THIRD PARTIES INCLUDING
ITS AUTHORIZED DEALERS OR
INSTALLERS. Unit must be returned to
Directed, postage pre-paid, with: consumer’s
name, telephone number, and address,
authorized dealer’s name and address, and
product description. IN ORDER FOR THIS
WARRANTY TO BE VALID, YOUR UNIT
MUST BE SHIPPED WITH PROOF OF
INSTALLATION BY AN AUTHORIZED
DIRECTED DEALER. ALL UNITS RECEIVED
BY DIRECTED FOR WARRANTY REPAIR
WITHOUT PROOF OF DIRECTED DEALER
INSTALLATION WILL BE COVERED BY THE
LIMITED 1-YEAR PARTS AND LABOR
WARRANTY. Note: This warranty does not
cover labor costs for the removal and rein-
stallation of the unit. BY PURCHASING THIS
PRODUCT, THE CONSUMER AGREES AND
CONSENTS THAT ALL DISPUTES BETWEEN
THE CONSUMER AND Directed SHALL BE
RESOLVED IN ACCORDANCE WITH CALI-
FORNIA LAWS IN SAN DIEGO COUNTY,
CALIFORNIA.

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© 2004 Directed Electronics, Inc
High-powered car audio systems may
produce sound pressure levels that
exceed the threshold at which hearing
loss may result.
They may also impair a driver’s ability to
hear traffic sounds or emergency vehi-
cles. Use common sense and practice
safe listening habits when listening to or
adjusting your audio system.
WARNING
FEATURES
High-speed MOSFET switching
power supply and complimentary
bipolar outputs.
Stereo, mono, or simultaneous
stereo/mono operation.
Thermal, DC offset, reverse polarity.
Selectable 12dB/octave two-way
crossover.
Switchable 8 dB bass EQ function.
Variable input sensitivity optimizes
match with different signal sources.
Chrome-plated wire terminals and
RCA connectors ensure maximum
signal transfer.
Rugged two-piece extruded heat
sink and cover.
Unity gain pass-through RCA jacks.

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© 2004 Directed Electronics, Inc
INSTALLATION GUIDELINES
1. Please read this owner’s manual
carefully before installing this ampli-
fier.
2. Disconnect the battery ground
terminal prior to making any elec-
trical connections.
3. Check for any hazards or obstruc-
tions such as gas tanks, fuel or
brake lines, and wiring harnesses
before mounting the amplifier.
4. Pick a mounting location that will
provide adequate access and venti-
lation and protect the amplifier
from heat, moisture, and dirt.
5. Avoid sharp metal areas when
routing cables to the amplifier, and
run RCA cables away from the
power cables and other potentially
noisy car harnesses.
6. The amplifier should be grounded
with a short, heavy gauge wire
connected directly to the car at a
bare metal surface, preferably
scraped body sheet metal. Do not
use factory ground locations, seat
bolts, or brackets that are spot
welded.
7. Always fuse your power connection
within 8 to 10 inches of the battery
terminal. Use a fuse or circuit
breaker rated slightly more than the
on-board fuse(s) of the
amplifier(s). The gauge of power
wire used should take into account
the total current draw of the
system, and the length of wire
used. IASCA and other auto sound
competition organizations have
charts available for this; you can
also find a chart in the MECP study
guide. Minimum wire gauge recom-
mendations for the individual ampli-
fiers are listed on the specification
page. Always use the same gauge
wire for the amplifier ground that
you use for the power wire. Be sure
to examine the battery ground
cable of the vehicle, and if neces-
sary, upgrade it by adding an addi-
tional ground wire that is the same
gauge as the amplifier power wire.
Remember, the amplifier can only
deliver its rated output when it is
not current limited by the power
and ground supply wires.
8. This amplifier is designed to drive a
speaker load that measures from 2
to 8 ohms. Keep in mind that heat
is the long-term enemy of automo-
tive electronics and the lower your

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© 2004 Directed Electronics, Inc
speaker load, the more heat is
generated. For low impedance
speaker applications or restricted
ventilation installations, an external
cooling fan may be advisable.
9. Battery and ground connections to
the vehicle should be made with
crimped ring terminals of the appro-
priate size (surface area is what
counts); soldering the terminals
after crimping is also recom-
mended.
10. Due to the high-frequency MOSFET
switching power supply, filtering the
power cable is not generally
required (remember that the amp
can’t deliver full output if the power
supply is restricted). Proper
grounding of the signal source is
mandatory for the amplifier to
reach its performance peak. If the
RCA inputs are not grounded
adequately via the signal source,
electrical noise from the vehicle
may be picked up in the system.

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© 2004 Directed Electronics, Inc
1. RRCCAAIInnppuuttJJaacckkss--Accepts line level
outputs from head units or signal
processors at voltages between
150mV and 7.5 volts.
2. RRCCAAOOuuttppuuttJJaacckkss--These pass
through RCA jacks can be used to
send the input signal to a second
amplifier.
3. GGaaiinnCCoonnttrrooll--Controls amplifier
sensitivity and is used to match the
input level of the amplifier to the
output level of the signal source.
4. CCrroossssoovveerrSSeelleeccttiioonnSSwwiittcchh--
Controls the type of filter for the on-
board active crossover. FLAT does
not attenuate any frequencies and
is for full-range speaker systems.
HPF attenuates low frequencies and
is used for mid-range speakers and
tweeters. LPF attenuates high
frequencies and is used for
subwoofers speakers.
5. BBaassssEEQQSSwwiittcchh- Adds an additional
8 db of boost to the speaker output
when on.
6. LLiigghhttBBaarr//FFaann- Allows connection
of an ooppttiioonnaallLED light bar or
ooppttiioonnaalladditional cooling fan for
the amplifier.
7. SSttaattuussLLEEDD- Will illuminate GREEN
to indicate the amplifier is on and
operating normally, and will be illu-
minated RED if the amplifier shuts
down due to short circuit, DC offset,
or overheating detected by on-
board protection circuitry.
8. IInnppuuttMMooddeeSSwwiittcchh- Selects 2 or 4
channel operation (model A404
only).
FRONT PANEL CONNECTIONS/CONTROLS A502-A404
FIGURE 1—AMPLIFIER CONNECTIONS A502 FRONT
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1. PPoowweerrFFuussee--This fuse protects the
amplifier against internal electrical
damage and is meant to protect the
amplifier only. All other power
connections should be fused at the
source. The A502 uses 1-30A fuse,
and the A404 uses 1-30A fuse.
2. ((++))1122VVoollttPPoowweerr- Connect this
terminal through a FUSE or CIRCUIT
BREAKER to the positive terminal of
the vehicle battery or the positive
terminal of an isolated audio
system battery.
WWAARRNNIINNGG::Always protect this power wire by installing a fuse
or circuit breaker of the appropriate size within
12 inches of the battery terminal connection.
3. RReemmootteeTTuurrnnOOnn- This terminal
turns on the amplifier when (+) 12
volt is applied to it. Connect it to
the remote turn on lead of the head
unit or signal source.
4. GGrroouunndd--Connect this terminal
directly to the sheet metal chassis
of the vehicle using the shortest
wire necessary to make this
connection. Always use wire of the
same gauge or larger than the (+)
12 volt power wire. The chassis
connection point should be scraped
free of paint and dirt. Use only
quality crimped and/or soldered
connectors at both ends of this
REAR PANEL CONNECTIONS
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© 2004 Directed Electronics, Inc
FIGURE 2—AMPLIFIER CONNECTIONS A404 FRONT
1234567
8
BLACK
BLUE
BLACK
RED
-
+
-
+
TO LEDs
TO FAN
FIGURE 5—LED/FAN HARNESS

99
12345
FIGURE 3—AMPLIFIER CONNECTIONS A502 REAR
© 2004 Directed Electronics, Inc
12345
FIGURE 4—AMPLIFIER CONNECTIONS A404 REAR
wire. DO NOT connect this terminal
directly to the vehicle battery
ground terminal or any other
factory ground points.
5. SSppeeaakkeerrTTeerrmmiinnaallss- Connect the
speakers to these terminals. (Refer
to the
Wiring Diagram section of
this guide.)

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© 2004 Directed Electronics, Inc
SPEAKER WIRING DIAGRAMS A502
L CH
R CH
B
R
I
D
G
E
D
L CH
R CH
INDUCTOR
CAP
CAP
SUB
Stereo operation (top view)
Mono operation (top view)
Simultaneous stereo/mono operation (top view)
B
R
I
D
G
E
D
L CH
R CH

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© 2004 Directed Electronics, Inc
SPEAKER WIRING DIAGRAMS A404
NNOOTTEE::For bridged two channel operation as shown in this diagram, connect right channel RCA cables to the front inputs of the
amplifier, and left channel RCA cables to the rear inputs of the amplifier. For summed subwoofer applications, connect
RCA cables per the input jack marking.
Stereo Operation - 2 Channel (top view)
B
R
I
D
G
E
D
L CH
R CH
B
R
I
D
G
E
D
L CH
R CH
FRONT
(RIGHT)
REAR
(LEFT)

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© 2004 Directed Electronics, Inc
Simultaneous Stereo (top view)
B
R
I
D
G
E
D
L CH
R CH
INDUCTOR
CAP
CAP
SUB
B
R
I
D
G
E
D
L CH
R CH
INDUCTOR
CAP
CAP
SUB
REAR
FRONT
Stereo Operation - 4 Channel (top view)
B
R
I
D
G
E
D
L CH
R CH
B
R
I
D
G
E
D
L CH
R CH
FRONT
(LEFT)
REAR
(LEFT)
REAR
(RIGHT)
FRONT
(RIGHT)

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© 2004 Directed Electronics, Inc
B
R
I
D
G
E
D
L CH
R CH
B
R
I
D
G
E
D
L CH
R CH
SUB
REAR
(LEFT)
REAR
(RIGHT)
2 Channel Stereo with Mono Sub (top view)

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© 2004 Directed Electronics, Inc
CROSSOVER SETTINGS AND GAIN ADJUSTMENT
Your Directed Audio power amplifier needs to be adjusted carefully to achieve
maximum performance. These are some guidelines to follow when fine-tuning the
amplifier.
For full-range and simultaneous stereo/mono bass applications, the crossover
selection switch should be set to FLAT. If the amplifier is driving your subwoofers,
set the switch to LPF, and for mid-bass/midrange output, set to HPF.
The gain adjustment allows you to set proper signal match for clean, quiet ampli-
fier operation. For full-range and simultaneous stereo/mono bass applications,
start by playing some music you are familiar with. With the gain adjustment on
the amplifier in the middle of its rotation, bring up the volume on your head unit
to the 3/4 volume setting or until you start to hear distortion or clipping. If you
hear distortion before you reach the 3/4 volume setting of your head unit, reduce
the gain setting on the amplifier and start to raise the head unit volume again.
When you can listen to the music at or slightly above 3/4 on your head unit
without audible distortion, slowly raise the gain of the amplifier until distortion is
heard, then back off the gain until the distortion is not audible. This setting will
allow you to reach full output with all but the quietest of source material, while
avoiding excessive noise in the system.
The same procedure should be used for adjusting the amplifier when the on-board
crossover is set to LPF or HPF, but you will also have to take into consideration the
effect that gain adjustment has on system frequency response and imaging.
Again, plan on spending some time with music that you know, getting the gain
and crossover settings the way you like. Test discs and analyzers may help with this
process, but in the end it's your ears that count - listen to the music!

1155
© 2004 Directed Electronics, Inc
LED TUBE INSTALLATION (OPTIONAL)
This Directed Audio amplifier has been designed with a custom heat sink that can
accommodate two (optional—not supplied) VARAD LED tubes.
1. Before installing the LED tubes, remove and discard the mounting feet from the
VARAD LED tubes.
2. Slide each LED tube assembly into your Directed Audio amplifier heat sink. Ensure
that the LEDs are facing out for optimal visibility. The wires from the LED tube
assembly should be on the signal input end of the amplifier. The Black wire from
the LED tube is ground and the Black/White wire from the LED tube is power.
4. Run the two wires from the tube assembly and connect them to the 4-pin
LED/FAN input connector. Refer to the LED/FAN harness diagram given earlier in
this manual.
NNOOTTEE::If the optional fan IS NOT being used, it is recommended that the second LED tube be wired to this circuit. If the optional
fan is being used, it is recommended that the second LED tube be wired in parallel with the first LED tube.
Directed Amplifier—VARAD Cross Reference Chart
Directed Part Number Directed Model VARAD Model QTY Required
45120 A502 HLX6, HL6, HLW9 2
45125 A802 HLX6, HL6, HLW9 2
45150 A404 HLX6, HL6, HLW9 2
45155 A1004 HLX12, HL12, HLW15 2
45095 D600 HLX6, HL6, HLW9 2
45100 D800 HLX6, HL6, HLW9 2
45105 D1200 HLX6, HL6 2
45110 D2400 HLX12, HL12 2
45165 D2205 (2) HLX12, (2) HL12 2 or 4
Use the following cross reference chart to select the proper length VARAD LED tube for
use with your Directed Audio amplifier.

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© 2004 Directed Electronics, Inc
CEA SPECIFICATIONS
AA550022
Power Output: 90 Watts RMS x 2 at 4 ohms and < 1% THD+N
Signal to Noise Ratio: -70 dBA (reference 1 Watt into 4 ohms)
Additional Power: 125 Watts RMS x 2 at 2 ohm and < 1% THD+N
AA440044
Power Output: 45 Watts RMS x 4 at 4 ohms and < 1% THD+N
Signal to Noise Ratio: -80 dBA (reference 1 Watt into 4 ohms)
Additional Power: 50 Watts RMS x 4 at 2 ohm and < 1% THD+N

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© 2004 Directed Electronics, Inc
SPECIFICATIONS
AA550022AA440044
RMS continuous
Power 4 Ohm 175W x 2 35W x 4
RMS continuous
Power 2 Ohm 2125W x 2 50W x 4
RMS continuous Power
Bridged 4 Ohm 3250W x 1 100W x 2
Dynamic Power Rating
(IHF-202 Standard) 4 Ohms 200W 300W
Signal-to-Noise Ratio Greater than 90 dB Greater than 90 dB
Frequency Response 20-20,000 Hz ± 0.25 dB 20-20,000 Hz ± 0.25 dB
Damping Factor Greater than 100 Greater than 100
Crossover Switchable high or low pass
12 dB/octave,100Hz
Switchable high or low pass
12 dB/octave,100Hz
Bass Equalization +8 dB, centered at 40Hz +8 dB, centered at 40Hz
Input Impedance 20K ohms 20K ohms
Input Sensitivity Variable from 250 mV to
7.5 volts
Variable from 250 mV to
7.5 volts
Output Impedance 2 to 8 ohms, stereo
4 to 8 ohms, bridged
2 to 8 ohms, stereo
4 to 8 ohms, bridged
Supply Voltage 10 to 16 VDC 10 to 16 VDC
Fusing and Power 30A 30A
Minimum Cable Requirements
(AWG) (Per amp, trunk
mounted)
#10 #10
1. RMS continuous power driven into 4 ohms from 20 to 20,000 Hz @ 14.4VDC with less
than 0.08% THD+N.
2. RMS continuous power driven into 2 ohms from 20 to 20,000 Hz @ 14.4VDC with less
than 0.15% THD+N.
3. RMS continuous power bridged into 4 ohms from 20 to 20,000 Hz @ 14.4VDC with
less than 0.15% THD+N.

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© 2004 Directed Electronics, Inc
The company behind this system is Directed Electronics, Inc. Since
its inception, Directed has had one purpose, to provide customers with the finest
vehicle security, car stereo products, rear seat entertainment, and accessories avail-
able. The recipient of more than 20 patents in the field of advanced electronic tech-
nology, Directed is ISO 9001 registered.
Directed® is committed to delivering world-class quality
products and services that excite and delight our customers.
Directed Electronics, Inc.
Vista, California 92081
www.directed.com
Quality Directed products are sold and serviced throughout North America and around the world
Call 800 274 0200 for more information about our products and services
© 2004 Directed Electronics, Inc. - All rights reserved - G45120.150 12/04