DLS AMPREFEN User Manual

OWNERS MANUAL

CAR AUDIO AMPLIFIERS

Reference 100A
Reference 200A

NOTE!

Read this manual thoroughly

before you start to install

DLS Svenska AB

Box 13029

SE-402 51 Göteborg

Sweden

Phone [phone]

Fax [phone]

E-mail: [e-mail]

www.dls.se

TABLE OF CONTENTS

Congratulations, you have just purchased the finest auto stereo amplifier that today´s technology can offer.
DLS offers a series of high quality car audio products for real music lovers, and we are sure that you will
enjoy a high class car sound for many years.

NOTE, read the owners manual first!

To maximize the performance of your system, we recommend that you thoroghly acquaint yourself with it´s
capabilities and features. Please take your time to study this manual before starting the installation. Then
you hopefully know how to do a correct installation avoiding connecting errors that can cause damage to
this fine product. Retain this manual for future reference.

TABLE OF CONTENTS:

Page 2 1. GENERAL PRODUCT INFORMATION
Page 2 2. INSTALLATION PREPARATION

Page 2 2.1 Location
Page 2 2.2 Power cables
Page 3 2.3 Signal cables
Page 3-4 2.4 Speaker connection, speaker loads, speaker polarity check
Page 4 2.5 Bridge mode - multimode operation
Page 5 2.6 Passive crossovers
Page 5 2.7 Level setting
Page 5 2.8 Final system setup
Page 5 2.9 Protection circuits

Page 6 3. INTERNAL FILTERS
Page 6 3.1 Reference 100A
Page 6 3.2 Reference 200A

Page 6 4. FAULT FINDING GUIDE
Page 6 4.1 Noise problems

Page 7 5. CONNECTION DIAGRAMS Reference 100A
Page 7 5.1 With one speaker pair in stereo
Page 8 5.2 With two speaker pairs parallel in stereo
Page 8 5.3 With one subwoofer in mono bridge mode
Page 9 5.4 In multimode operation

Page 10 6. CONNECTION DIAGRAMS Reference 200A
Page 10 6.1 With a front and a rear system in stereo
Page 11 6.2 With a front system in stereo and a subwoofer in mono bridge

mode

Page 12 6.3 With a front system in stereo, a rear system in stereo and a

subwoofer in multimode operation.
Page 13 6.4 With a stereo speaker system connected in bridge mode
Page 14 6.5 With a 3-way stereo system using the built-in active crossover.

Page 15 7. SPECIFICATIONS
Page 16 For your own notes

CAUTION!

Some of our amplifiers are capable of producing a sound pressure level that can cause permanent
damage to your hearing system. High sound pressure levels combined with long time listening can give
permanent damage to your hearing system. Choose a listening level that is comfortable for your ear.
To establish a safe level:
Start your volume control at a low setting. Slowly increase the volume until you can hear the music
comfortly and clearly, without any distortion. Sudden sound shocks are dangerous.

The following noises can be dangerous with constant exposure:

90 dB Subway, motorcycle, lawn mover 4 hours max
100 dB Chain saw 2 hours max
120 dB Rock band live concert 30 minutes max
140 dB Gunshot blast, jet plane 0 minutes

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GENERAL, POWER CABLING

1. GENERAL PRODUCT
INFORMATION

Thank you for buying a DLS amplifier. This amplifier
is a high quality product and is a result of many
years of experience of building high quality sound
products for vehicles.

We recommend you to carefully read this manual
before you start to install. Be sure to follow all
recommendations in the installation section. If you
do so we are sure that you will be able to enjoy a
perfect sound for a long time,.

2. INSTALLATION PREPARATION

Sections 2 - 4 in this manual are common for both
amplifiers. In section 5 & 6 you will find connection
diagrams for each amplifier model.

2.1 LOCATION

We recommend you to do a careful planning before
you start to install this equipment.
Choose a location for the amplifier which will allow
plenty of air to circulate around the fins on the top of
the case. Vertical mounting is to prefer. Do NOT mount
the amplifier upside down under the hat rack.
In the amplifier case there are double mounting holes
to make the installation job easier. The screws
supplied in the plastic bag are self drilling when used
with an electric screwdriver.
If the surface where you intend to mount the amplifier
isn´t big enough you can mount the amplifier on a
separate fibre board or similar. This will also isolate
the amplifier chassies from ground.

NOTE! Before you start drilling, make sure that
there are no fuel or brake lines or wiring looms
behind where you intend to drill.

2.2 POWER CABLES

The DC power wiring is extremely important. It is
essential that the amplifier at all occassions gets all
the power it needs without voltage drop, otherwise
both the dynamics and the good sound will be lost.
A poor battery can also cause a bad sound
reproduction, escpecially in the bass range. Some­times it is necessary to mount an extra battery.
All cable connections requires a 2 mm hexagon key
to connect the terminals.

In most cases a so called ”Power Cap” can be useful.
It is an energy storage capacitor designed to supple­ment audio amplifiers during high current demand.
The overall bass response of your audio system will
be enhanced with the use of this due to it´s ability to
store a large amount of current and discharge it in a
short period of time.

In the table below you will find suitable cable areas
and fuse sizes for different cable lenghts.
The gold plated terminals will directly recieve
power cables up to 16 mm2 (5AWG).
Mount a fuse holder (DLS FH 1 or similar) on the DC

-cable near the positive battery terminal. Use the
same cable size from the negative amplifier terminal
and connect to the nearest earth point.
Make sure to have a good earth contact, if necessary
clean the metal from paint etc. A poor earth contact
can cause damage to other parts in the system, for
example the head unit if the earth current is forced to
pass through the shield of the signal cable.

Recommended cable size for the DC-feed.
Cable length: < 1,5 m 1,5 - 5 m > 5 m

Amplifier:

Ref. 100A 10 mm216 mm
Ref. 200A 16 mm221 mm

Recommended main fuse for the amplifiers:
Amplifier Fuse value Fuse holder

Ref. 100A AGU 40 A FH1/FH1B
Ref. 200A AGU 60 A FH1/FH1B

A cable of a certain size can´t have an oversized fuse,
then the cable gets too warm before the fuse blows.

Max fuse values for different cable sizes:

6 mm2 (9 AWG) 25 A
10 mm2 (7AWG) 40 A
16 mm2 (5AWG) 60 A
21 mm2 (4AWG) 100 A
33 mm2 (2AWG) 140 A
42 mm2 (1AWG) 200 A

If you have more than one amplifier in the system
you must increase the cable size and fuse compared
to the table. When connecting two or more amplifiers
use some of the DLS Fuse blocks with built in fuses
to split the power to each amplifier. The short cable
from the Fuse block to the amplifier can have a smal­ler size for easier installation.
Don´t connect to battery before you have double
checked all connections.

Fuse block

Fuse

Battery 12 V

2

21 mm

2

33 mm

Two amplifiers

2
2

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CABLING, SIGNAL CABLES, SPEAKER CONNECTION

2.3 SIGNAL CABLES

Reference 100A has one gold plated phono socket

pair provided to recieve the signal from the head unit.
Reference 200A has two phono socket pairs. One for
each amplifier part.
When the amplifier is being operated in bridge mode
both inputs must recieve an input for full power out­put.

Use high quality interconnects like the DLS SL5 PRO
or similar with an effective shielding that prevents
interference from the engine or alternator. When
using this cable you must run a separate wire for the
remote.

When you run the signal cables remember to keep
them well spaced from the wiring loom and the power
feed to the amplifier to avoid picking up interference.
Lay the power cables and signal cables separated
on each side of the car. Any extra cable must be laid
in zig-zag style and definitely not coiled. Or cut it to
correct lenght.

REMOTE WIRE

Some signal cables include a thin wire for remote
amplifier start. High quality cables normally requires
a separate wire for this. Connect between the head
units remote cable (often the same cable that´s used
for automatic power antennas) and the REM-termi­nal on the amplifier.

NOTE! If you want to start more than one amplifier
using the remote output, the current load might be
too high for som head units. High currents may
damage the head unit, check in the manual for the
head unit. Sometimes you must add a relay to the
remote circuit that takes care of the higher current. If
you are uncertain of how to connect the relay, ask
your local DLS dealer for advice.

2.4 SPEAKER CONNECTION

The gold plated terminals will directly recieve
speaker cables up to 6 mm2 (9AWG). Always
use high quality speaker cables such as DLS
SC 2x1,5, SC 2x2,5 or SC 2x4. Subwoofer
connection requires 2 x 4 mm2 cable.
Connect the speaker + (marked with + or a red
dot) to the amplifier + terminal, and the speaker

- to the amplifier -.
When fitting the cables to the terminals, remove
only 10 mm of the insulation. Twist the wire
strand together and insert the wire after
loosening the terminal screw. Do not over tighten
as this can cut the cable strands. Use a 2 mm
hexagon key to the terminals.

PROTECT YOUR CABLES!

To prevent the cable insulation from beeing damaged
over sharp metal edges we recommend the use of
cable protection tubes or similar. A damaged cable
insulation could cause serious damage to the amplifier
not covered by any guarantee.

SPEAKER POLARITY CHECK.

All speakers in a car audio system should be
connected in phase (the same polarity). All speaker
cones must move in the same direction. Out of phase
speakers will cause a lack of bass, and a poor stereo
soundstage.

Checking polarity:

Hold the - connection of the speaker wire to the ­terminal of a 1,5 Volt flashlight battery. Tap the + wire
on to the + terminal of the battery, and observe the
movement of the cone. The cone should move
outwards when the wire touches the battery, and
inwards when the battery is removed. If it is the other
way around, the speaker has been connected
backwards and it must be removed and connected
correctly.
If your system also has a subwoofer connected
through a passive 6 or 12 dB crossover, try to connect
this with various polarity and judge what sounds best.
The phase shift in passive crossovers sometimes
makes it necessary to change polarity.

+

Battery
1,5
Volt

+

-

-

NOTE! Tweeters can not be tested this way, double

check the connections instead.

SPEAKER LOADS

Most car audio speakers have a 4 ohm impedance.
DLS amplifiers can be loaded down to 2 ohm on each
stereo channel.
In mono bridge mode operation the speaker load must
never be less than 4 ohm. If you are using more than
one driver they must be connected in a way so the
impedance still is 4 ohm when connected to the
amplifier. When you run the amplifier in mono bridge
mode it sees a 4 ohm load as 2 ohm. On page 4 you
find different speaker wiring examples.

Don´t forget that the output power from a multimode
connected amplifier is more than double the normal
power. The speakers must be able to handle this
power.

If you want an extra high class speaker cable
choose any of the DLS SCP, SCK, SC 4x1 or
SC 4x1,5 cables.

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SPEAKER LOAD, BRIDGE MODE OPERATION

SPEAKER CONNECTION EXAMPLES

TWO 4 OHM SPEAKERS IN PARALLEL.

++

2 ohm

-

NOTE ! Not for bridge mode operation.

TWO 4 OHMS SPEAKERS IN SERIES.

+

8 ohm

-

Not a recommended way to connect, the power is
only half.

+

--

+

-

+

MULTIMODE OPERATION

Multimode operation means that you connect one or
two systems in normal stereo mode and then add
one or more subwoofers in mono bridge mode to the
same speaker terminals. A center channel can be
connected in the same way.
To avoid amplifier overload you must ALWAYS use
passive filters in multimode operation. The subwoofer
needs a 12 dB lowpass crossover and the stereo
system needs a 6 or 12 dB highpass crossover.

MULTIMODE OPERATION SCHEMATIC

-

Left
channel

+

C1

23456

23456

L

C2

-

+

+

SERIES / PARALLEL TO 4 OHM.

++

+

Each

4 ohm

-

speaker
is 4 ohm

-

+

-

-

+

-

CAUTION!
In mono bridge mode the
speaker impedance must
never be less than 4 ohms.
The amplifiers sees a 4 ohm speaker
as a 2 ohm load.

2.5 BRIDGE MODE OPERATION

Subwoofers are normally connected in mono bridge
mode to the amplifier. This is done by connecting
the speaker + to the amplifiers LEFT+ terminal,
and the speaker - to the amplifiers RIGHT- termi­nal.
Now the speaker will recieve a signal that is the sum
of the signals from each channel.

-

-

-

Mono connected

Right
channel

C1

+

+

Right system Left system

This drawing shows a mono multimode connected
subwoofer together with a normal stereo system.

The subwoofer crossover frequency is 95 Hz
(12 dB lowpass filter).
The stereo system crossover frequency is 140 Hz
(6 dB highpass filter).

Components with 4 ohm speakers:

C1 = 200 µF
C2 = 300 µF
L = 10 mH with low resistance, 0,5 - 0,7 ohm

Do not use the amplifiers internal lowpass cross­over.
Use only the amplifiers internal highpass crossover
as a SUBSONIC filter adjusted to approx. 30 Hz.

subwoofer

- 4 -

PASSIVE FILTERS, LEVEL SETTING, FINAL SYSTEM SETUP

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2.6 PASSIVE CROSSOVERS

12 dB highpass crossover:

+

For maximum use of the DLS amplifiers it´s useful to
know a little about passive crossover design. Passive
crossovers are often used for conncting subwoofers

-

in multimode operation or for center channel speakers.
To remove frequencies over a certain frequency (the
crossover frequency) use a filter with a 6 or 12 dB
slope. This type of crossover is often used in
combination with a subwoofer.

X-over freq. Coil Capacitor

95 Hz 10 mH 300 µF
140 Hz 6,3 mH 200 µF
190 Hz 4,7 mH 150 µF
All valid for 4 ohm speakers.

6 dB lowpass crossover:

Consists of a coil connected in series with the driver.

NOTE! All DLS amplifiers are equipped with internal
low- and highpass crossovers. External passive
crossovers are used only in multimode operation.

234567

234567

+

-

20 mH 10 mH 6,3 mH
2Ω 64 Hz 32 Hz 50 Hz
4Ω 128 Hz 64 Hz 101 Hz
8Ω 256 Hz 128 Hz 203 Hz

This table shows the crossover frequency of a 6 dB
lowpass filter at different impedances and frequencies.

12 dB lowpass crossover:

Consists of a coil in series and a bipolar capacitor
connected in parallel with the driver.

234567

+

234567

-

X-over freq. Coil Capacitor

62,5 Hz 14 mH 450 µF
95 Hz 10 mH 300 µF
140 Hz 6,3 mH 200 µF
Valid for 4 ohm speakers only.
This type is normally used for subwoofers.

If you want to limit the lower frequency response, for
example to a stereo system in multimode operation,
a 6 dB slope crossover is perfect. Just connect a
bipolar capacitor in series with the driver.

6 dB highpass filter:

2.7 LEVEL SETTING

To adapt the amplifier to all kind of signal sources
with varying levels there are gain controls provided
on the amplifier next to the phono sockets. They
should not be used as volume controls.
Start with a ”12 o clock” setting of the level controls. If
you set the head unit volume to 75% of maximum
you should achieve a good sound without distortion.
Find a point of the level setting where the distortion is
just discernible. At this point slightly reduce the control
to eliminate the distorsion.
On a multi channel amplifier like the Reference 200A
it´s necessary to adjust the levels indiviually to achieve
a good sound balance between the different speakers,
different speakers have different sensitivity. When
using two of the channels for subwoofer operation,
start the level adjustment on these channels. After
having adjusted the bass level for good performance,
adjust the level to the front system for a good sound
balance. In multimode operation you can´t adjust the
subwoofer level separately.

2.8 FINAL SYSTEM SETUP

Before connecting the amplifier to the battey, recheck
all connections. When you connect the main fuse
you will see a little spark, this is normal. But if the
fuse blows at this moment, something is wrong.
Recheck the cabling.
Turn on your head unit, the amplifier starts and the
red LED is lit. Increase the volume and make sure
all speaker works. Readjust levels and crossover
settings if necessary. The level settings might need
to be readjusted after 25 - 30 hours of use.

2.9 PROTECTION CIRCUITS

+

-

300 µF 200 µF 150 µF
2Ω 266 Hz 400 Hz 533 Hz
4Ω 133 Hz 200 Hz 266 Hz
8Ω 67 Hz 100 Hz 133 Hz

This table shows the crossover frequency of a 6 dB
highpass filter at different impedances and frequencies.

The amplifiers have an internal high current protection
circuit shutting down the amplifier if the current draw is
too high. It is indicated with a yellow LED. The protection
circuits will reset by turning the head unit off and on
again. There are two 25 Amp fuses on the front.
Disconnect the main fuse before replacing any of these.
Always replace with the same type and value.
The amplifiers also have a thermal protection that turns
off the amplifier at 95 C. It will resume operation after
cooling down. If necessary install an external cooling
fan.

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