Ssl STA208, STA206, STA212, STA216, STA220 User Manual

CONTENTS

STEALTH MOSFET Amplifier User’s Manual - page 1

U S E R ’ S M A N U A L

2 Introduction

2 What is included?

3 Features

3 About 2 Ohm operation

4 General precautions

4 Installation precautions

4 Mounting the amplifier

5 Connecting the amplifier

6 Low level input wiring

7 High level input wiring

8 2CH Power and Speaker wiring

2CH Mode

9 2CH Power and Speaker wiring

Bridged Mode

10 2CH Power and Speaker wiring

TriMode

11 4CH Power and Speaker wiring

4CH Mode

12 4CH Power and Speaker wiring

Bridged Mode

13 4CH Power and Speaker wiring

TriMode

14 Troubleshooting

15 Specifications

Congratulations on your
purchase of a
Sound Storm Laboratories
STEALTH Amplifier.

It has been designed, engineered
and manufactured to bring you
the highest level of performance
and quality, and will afford you
years of listening pleasure.

Thank you for making Sound
Storm Laboratories your choice
for car audio entertainment!

page

STA220
STA216

STA212
STA208
STA206

Two Channel
MOSFET Car Audio
Amplifiers

STA416
STA412

Four Channel
MOSFET Car Audio
Amplifiers

STEALTH MOSFET Amplifier User’s Manual - page 2

Introduction

With the Sound Storm Laboratories

STEALTH MOSFET amplifier series,

we are introducing seven new
amplifiers, all designed in the USA.
This new series includes five 2-channel
and two 4-channel amplifiers.

All STEALTH models feature variable

low pass crossovers and variable input
gain controls. They also incorporate a
fixed high pass crossover for added
system flexibility.

For further flexibility in the use of a
subwoofer, 0-+18dB Bass Boost
control has been included on all
amplifiers. You can control the
subwoofer level with the remote level
control module.

Sound Storm Laboratories
understands that amplifiers are placed
in many different kinds of installations,
so we incorporated a very flexible
system of controls in these amplifiers
in order to help you integrate the amp
into your system regardless of the
nature of your input source.

What is included?

When first unpacking your new
amplifier, please check first that the
package contains all of the items
below. If something is missing, contact
the store where you purchased the
amplifier.

• STEALTH amplifier

• Remote subwoofer level control

•High input cable with connector

• Four (4) mounting screws

STEALTH MOSFET Amplifier User’s Manual - page 3

Features About 2 Ohm operation

Your new STEALTH amplifier features
the following:

• Class A-B operation

• Bridgeable outputs

• Tri-Mode capable

• MOSFET PWM (Pulse Width
Modulated) Power Supply

• 2 Ohm stable stereo operation
with output power increase

• Thermal and speaker short
protection

• Soft turn-on circuit

• Remote turn-on/turn-off circuit

• Variable input gain control

• Variable low pass crossover(s)

• Fixed high pass crossover (200Hz)

• Variable 0 to +18dB Bass Boost

• Nickel-plated RCA low level and
high level inputs

• LED power and protection
indicators

• Silver anodized heatsink

• Remote subwoofer level control

Your STEALTH amplifier has been
designed to operate efficien

tly at loads
down to 2 Ohms. This means that you
can install four 8 Ohm speakers per
channel, when using parallel wiring.

Increasing the number of woofers per
channel at low frequencies (below
100Hz) produces an acoustic coupling
effect. This acoustic coupling effect
increases your power output by about
3dB per speaker, or the equivalent of
an additional 10W per speaker.

When operating at 2 Ohms, the
amplifiers will increase their output
power by approximately 50%. The

current draw will also increase by
about the same amount, so be sure
you have enough current to run the
amplifiers into a 2 Ohm load.

If you lack adequate current, your
music reproduction will be distorted.

STEALTH MOSFET Amplifier User’s Manual - page 4

General precautions

SHOCK HAZARD! Do not open the case
of this product. There are dangerous

voltages present within the unit. There are
no user-serviceable parts within the unit.

Before making or breaking power
connections in your system,
disconnect the vehicle battery. Confirm
that your head unit or other equipment
is turned off while connecting the input
jacks and speaker terminals.

If you need to replace the power fuse,
replace it only with a fuse identical to
that supplied with the amplifier. Using
a fuse of a different type or rating may
result in damage to your audio system
or your amplifier which is not covered
by the manufacturer's warranty.

Before installing and using your
new Sound Storm Laboratories
amplifier, please become familiar
with all the information contained
in this manual.

Please keep this manual in a safe
place for future reference.

• Do not open or attempt to repair
this unit yourself. Dangerous high
voltages are present which may result
in electric shock. Refer any repairs to
a qualified service technician.

• To avoid risk of electronic shock or
damage to the am

plifier, do not permit
any of this equipment to become
damp or wet from water or drinks. If
this does occur, immediately unplug
the power wires and send the amplifier
to your local dealer or service center

as soon as possible.

• If there is smoke or any peculiar
odor present during use or if there is
damage to any of the component
enclosures, immediately unplug the
power wire and send the amplifier to
your local dealer or service center as
soon as possible .

Installation precautions

Before you drill or cut any holes,

investigate your car's layout very

carefully. Take special care when you

work near the gas tank, fuel lines,

hydraulic lines and electrical wiring.

Never operate the amplifier when it is
unmounted. Attach all audio system
components securely to prevent

damage, especially in an accident.

Mounting the amplifier

1. Find a suitable location in the vehicle
in which to mount the amplifier.

2. Make sure there is sufficient air
circulation around the intended
mounting location.

3. Mark the location for the mounting
hole screws by positioning the amplifier
where you wish to install it. Use a
scribe

or mounting screw, inserted
through each of the amp's mounting
holes, to mark the mounting surface.
If the mounting surface is carpeted,
measure the hole centers and mark
with a felt tip pen.

4. Drill pilot holes in the mounting
surface for the mounting screws. Place
the amplifier in position, and attach
the amplifier to the mounting surface
securely using screws.

STEALTH MOSFET Amplifier User’s Manual - page 5

Before doing any wiring, look through
this manual and identify the diagrams
to follow for power, input and speaker
connections for your particular
installation. Be sure you understand
all the c

onnections before you proceed.

1. Connect the power ground terminal
to the closest point on the chassis of
the car. Keep this ground wire to less
than 39" (100 cm) in length. Use 8
gauge (or heavier) wire.

2. Connect the remote terminal to the
remote output of the head unit using
16 gauge (or heavier) wire.

3. Connect an empty fuse holder within
18" (45 cm) of the car battery, and run
8 gauge (or heavier) cable from this
fuse to the amplifier location.

4. Check that the fuse holder is empty.
Then connect the fuse holder to the
"BATT+" connection on the amplifier.

5. If multiple amplifiers are being used
in your system, either:

• Run a separate pair of cables from
the battery and a chassis ground point
to each amplifier. Each (+) cable must
have its own inline fuse.

-or-

• Run a #4 cable from the fuse holder
at the battery to a distribution block
at or near the amplifier's location. Then
run separate cables from the amplifier
to this distribution block and to
independent chassis ground points.

6. Connect all line inputs and outputs
(if used) using high-quality cables.
Connect all speakers, following the
diagrams in this manual.

Be sure to
observe proper polarity to avoid audio
phase problems.

Connecting the amplifier

7. Insert fuse(s) into the battery fuse
holder(s).

8. Recheck all connections before
powering up the amplifier.

9. Set all level controls to minimum
position, and set all crossover
controls/switches to the desired
frequency points.

10. Power up the head unit and the
amplifier. Then set the volume control
on the head unit to about 3/4 volume,
and adjust the amplifier’s input level
control(s) to just below the level of
distortion.

11. Further fine tuning of the various
controls may be necessary to obtain best
results.

Do not mistake the input level control
for a volume control! It is designed
ONLY to match the output level of
your audio source to the input level
of your amplifier.

Do not adjust this input level to
maximum unless your input level
requires it.

Ignoring these instructions will result
in an input overload to the amplifier,
and excessive audio distortion. It
can also cause the protection circuit
to engage.

Don't misuse the
level control!

STEALTH MOSFET Amplifier User’s Manual - page 6

Low Level Input Wiring

Low-level (RCA) input wiring is preferred for best audio performance. Always use
a high-quality RCA cable for best audio performance.

NOTE: Do not connect BOTH the high level and low level inputs from your
receiver to your amplifier at the same time!

2-Channel Amplifiers

STA206, STA208, STA212,
STA216 and STA220

To Audio

Outputs of head

unit or signal

processor

STA412 and STA416

4-Channel Amplifiers 4-Channel Amplifiers

To REAR Audio Outputs of

head unit or

signal processor

To FRONT Audio Outputs
of head unit or
signal processor

Remote
Subwoofer Level Control

Remote
Subwoofer Level Control

STEALTH MOSFET Amplifier User’s Manual - page 7

High Level Input Wiring

The high level input(s) should only be used when your head unit lacks RCA outputs.
If the RCA outputs are not present, connect the speaker outputs from the receiver
to the high level input connector of the amplifier. Be sure to observe polarity to
avoid audio phase problems.

NOTE: Do not connect BOTH the high level and low level inputs from your
receiver to your amplifier at the same time!

2-Channel Amplifiers

STA206, STA208, STA212,
STA216 and STA220

STA412 and STA416

4-Channel Amplifiers

To Speaker Terminals
of head unit

To Speaker Terminals
of head unit

L+ L- R- R+

CH

3-CH4+

CH

4-

CH

3+

Remote

Subwoofer Level Control

Remote

Subwoofer Level Control

To Speaker Terminals
of head unit

CH

1-

CH

2+

CH

2-

CH

1+

STEALTH MOSFET Amplifier User’s Manual - page 8

Power and Speaker Wiring

2 Channel Mode

STA206, STA208, STA212

STA216 and STA220

2-Channel Amplifiers

Two
Channel
Mode

SPEAKER

IMPEDANCE

2-8 OHMS

Connect the Positive (+) terminal of the
subwoofer to the R (+) amplifier terminal.

Connect the Negative (-) terminal of the
subwoofer to the L (-) amplifier terminal.

GN D RE M B AT T

+

FU SE S

L R

BR I D G E D MO D E

RIGHT

Speaker

LEFT

Speaker

to REMOTE TURN-ON
terminal of head unit

Chassis

ground

point

Battery

FUSE

STEALTH MOSFET Amplifier User’s Manual - page 9

Power and Speaker Wiring

Bridged Mode

STA206, STA208, STA212

STA216 and STA220

2-Channel Amplifiers

Connect the Positive (+) terminal of the
subwoofer to the R (+) amplifier terminal.

Connect the Negative (-) terminal of the
subwoofer to the L (-) amplifier terminal.

Bridged
Mode

SPEAKER

IMPEDANCE

4-8 OHMS

GN D RE M B AT T

+

FU SE S

L R

BR I D G E D MO D E

Subwoofer

to REMOTE TURN-ON

terminal of head unit

Chassis

ground

point

Battery

FUSE

STEALTH MOSFET Amplifier User’s Manual - page 10

Power and Speaker Wiring

Tri-Mode

STA206, STA208, STA212

STA216 and STA220

2-Channel Amplifiers

Tri-Mode

Tri-mode operation allows you to connect this amplifier to a pair of main speakers plus
a subwoofer on one pair of output channels. The main speakers will operate in STEREO
while the subwoofer simultaneously operates in MONO.

To set up the amplifier to run in this mode, put the crossover switches in the FULL position.
Insert high pass filter capacitors and a low pass filter inductor into the wiring as shown
below. Be sure to check the table at the bottom of this page to determine the correct
capacitor and inductor values for the crossover frequency you wish to achieve.

RIGHT
Speaker

LEFT
Speaker

Component values for
6dB Passive Crossover

FREQUENCY INDUCTOR CAPACITOR

80 Hz
100 Hz
120 Hz
150 Hz

7.5mH

6.5mH

5.5mH
4mH

470uF
330uF
330uF
220uF

SPEAKER

IMPEDANCE

8 OHMS

Four
Channel
Mode

GN D RE M B AT T

+

FU SE S

L R

BR I D G E D MO D E

Battery

FUSE

to REMOTE TURN-ON
terminal of head unit

Chassis

ground

point

Subwoofer

High pass filter
crossover

Low pass

filter inductor

High pass filter

crossover

MINIMUM
SPEAKER

IMPEDANCE

4 OHMS

STEALTH MOSFET Amplifier User’s Manual - page 11

Power and Speaker Wiring

4 Channel Mode

STA412 and STA416

4-Channel Amplifiers

Four
Channel
Mode

SPEAKER

IMPEDANCE

2-8 OHMS

SPEAKER

IMPEDANCE

2-8 OHMS

GN D RE M B AT T

+

FU SE S

CH2 CH1CH4 CH3

BR I D G E D M OD EBR I D G E D M OD E

CH3

Speaker

CH4

Speaker

CH1

Speaker

CH2

Speaker

to REMOTE TURN-ON
terminal of head unit

Chassis

ground

point

Battery FUSE

STEALTH MOSFET Amplifier User’s Manual - page 12

Tri-Mode

Power and Speaker Wiring

Bridged Mode

STA412 and STA416

4-Channel Amplifiers

Bridged
Mode

Connect the Negative (-) terminal of the RIGHT
subwoofer to the CH4(-) amplifier terminal.

Connect the Postive (+) terminal of the RIGHT
subwoofer to the CH3(+) amplifier terminal.

Connect the Negative (-) terminal of the LEFT
subwoofer to the CH2(-) amplifier terminal.

Connect the Postive (+) terminal of the LEFT
subwoofer to the CH1(+) amplifier terminal.

SPEAKER

IMPEDANCE

4-8 OHMS

SPEAKER

IMPEDANCE

4-8 OHMS

GN D RE M B AT T

+

FU SE S

CH2 CH1CH4 CH3

BR I D G E D M OD EBR I D G E D M OD E

RIGHT

Subwoofer

LEFT

Subwoofer

to REMOTE TURN-ON
terminal of head unit

Chassis

ground

point

Battery FUSE

STEALTH MOSFET Amplifier User’s Manual - page 13

Power and Speaker Wiring

Tri-Mode

STA412 and STA416

4-Channel Amplifiers

Tri-Mode

Tri-mode operation allows you to connect this amplifier to a pair of main speakers
plus a subwoofer on one pair of output channels. The main speakers will operate
in STEREO while the subwoofer simultaneously operates in MONO.

To set up the amplifier to run in this mode, put the crossover switches in the FULL
position. Insert high pass filter capacitors and a low pass filter inductor into the
wiring as shown below. Be sure to check the table at the bottom of this page to
determine the correct capacitor and inductor values for the crossover frequency
you wish to achieve.

CH1
Speaker

CH2
Speaker

Component values for
6dB Passive Crossover

FREQUENCY INDUCTOR CAPACITOR

80 Hz
100 Hz
120 Hz
150 Hz

7.5mH

6.5mH

5.5mH
4mH

470uF
330uF
330uF
220uF

SPEAKER

IMPEDANCE

8 OHMS

GN D R E M BATT

+

FU SE S

CH2 CH1CH4 CH3

BR I D G E D M O D EBR I D G E D M O D E

CH4
Speaker

RIGHT
Subwoofer

SPEAKER

IMPEDANCE

8 OHMS

MINIMUM
SPEAKER

IMPEDANCE

4 OHMS

Low pass

filter inductor

High pass filter
crossover

High pass
filter crossover

CH3
Speaker

LEFT
Subwoofer

+
–

+

–

High pass filter
crossover

Low pass

filter inductor

High pass filter
crossover

MINIMUM
SPEAKER

IMPEDANCE

4 OHMS

to REMOTE TURN-ON
terminal of head unit

Chassis
ground

point

Battery FUSE

Troubleshooting

STEALTH MOSFET Amplifier User’s Manual - page 14

If you experience operation or performance problems with this product, compare your
installation with the electrical wiring diagram on the previous pages. If problems persist,
read the following troubleshooting tips which may help eliminate the problems.

Amplifier will not
power up.

Check to make sure you have a good ground connection.

Check that the Remote Input (Turn-On) has at least 3VDC.
Check that there is battery power on the (+) terminal.

Check that there is at least 12v.
Check all fuses, replace if necessary.

Make sure that the Protection LED is not illuminated. If it is lit, shut off
the amplifier briefly, and then repower it.

Protection LED
comes on when
amplifier is
powered up.

Check for short circuits on speaker leads.
Turn down the volume control on the head unit to prevent overdriving.

Remove speaker leads, and reset the amplifier. If the Protection LED still
comes on, then the amplifier is faulty and needs servicing.

No output.

Check that all fuses are OK.

Check that amplifier is properly grounded.
Check that the Remote Input (Turn-On) has at least 3VDC.

Check that the RCA audio cables are plugged into the proper inputs.
Check all speaker wiring.

Low output.

Reset the Level Control.

Check the Crossover Control settings.

Audio present in
only one channel.

Check the RCA interconnect cables.

Check all speaker wiring.

High hiss in the
speakers.

Disconnect all RCA inputs to the amplifiers. If the hiss disappears, then
plug in the component driving the amplifier and unplug its inputs. If the
hiss disappears at this point, go on until the faulty/noisy component is
found.

It is best to set the amplifier's input level control as low as possible. The
best subjective signal-to-noise ratio is achieved in this manner. Try to set
the head unit as high as possible (without distortion) and the amp input
level as low as possible.

Squealing noise
from speakers.

Check for improperly grounded RCA interconnects.

Distorted sound.

Check that the Input Level Control is set to match the signal level of the
head unit. Always try to set the Input Level as low as possible.

Check that all crossover frequencies are properly set.
Check for short circuits on the speaker leads.

Amplifier gets
very hot.

Check that the minimum speaker impedance for the amp model is correct.

Check that there is good air circulation around the amp. In some
applications, it may be necessary to add external cooling fan(s).

Engine noise
(static type)

This is usually caused by poor quality RCA cables,which can pick up
radiated noise. Use only the best quality cables, and route them away
from power cables.

Engine noise
(alternator
whine)

Check that speaker leads are not shorted to the vehicle chassis.

Check that the RCA grounds are not shorted to the vehicle chassis.
Check that the head unit is properly grounded.

SYMPTOM POSSIBLE REMEDY

Specifications

STEALTH MOSFET Amplifier User’s Manual - page 15

All specifications subject to change without notice.

RMS POWER

into 4 Ohms

MAX POWER

into 2 Ohms

BRIDGED POWER

into 4 Ohms

Min. speaker
impedance

THD

Frequency response

Signal-to-noise ratio

Channel separation

Damping factor

Crossover range

low pass

high pass

Bass boost

Fuse rating

Dimensions:
(11-

1/4

" x 3" x ...)

MODEL STA412

Four C ha nn el MO SF ET Car Audi o Am plifier s

250W x 4

400W X 4

800W x 2

2 Ohm Stereo
4 Ohm Mono Bridged

0.01%

9Hz-50kHz

103dB

90dB

125+

35Hz-160Hz

200Hz (fixed)

Variable 0 - +18dB

25A x 2

13-3/4"

STA416

RMS POWER

into 4 Ohms

MAX POWER

into 2 Ohms

BRIDGED POWER

into 4 Ohms

Min. speaker
impedance

THD

Frequency response

Signal-to-noise ratio

Channel separation

Damping factor

Crossover range

low pass

high pass

Bass boost

Fuse rating

Dimensions:
(11-

1/4" x 3" x ...)

MODEL

Two Cha nnel MOS FET C ar A udio A mpl if iers

170W x 2

400W X 2

800W x 1

2 Ohm Stereo
4 Ohm Mono Bridged

0.01%

9Hz-50kHz

103dB

90dB

125+

35Hz-160Hz

200Hz (fixed)

Variable 0 - +18dB

25A x 1

9"

STA208

230W x 2

600W X 2

1200W x 1

2 Ohm Stereo
4 Ohm Mono Bridged

0.01%

9Hz-50kHz

103dB

90dB

125+

35Hz-160Hz

200Hz (fixed)

Variable 0 - +18dB

25A x 1

11"

STA212

290W x 2

800W X 2

1600W x 1

2 Ohm Stereo
4 Ohm Mono Bridged

0.01%

9Hz-50kHz

103dB

90dB

125+

35Hz-160Hz

200Hz (fixed)

Variable 0 - +18dB

20A x 2

12-1/2"

STA216

360W x 2

1000W X 2

2000W x 1

2 Ohm Stereo
4 Ohm Mono Bridged

0.01%

9Hz-50kHz

103dB

90dB

125+

35Hz-160Hz

200Hz (fixed)

Variable 0 - +18dB

25A x 2

17-5/8"

STA220

STA206

140W x 2

300W X 2

600W X 1

2 Ohm Stereo
4 Ohm Mono Bridged

0.01%

9Hz-50kHz

105dB

90dB

125+

40Hz-150Hz

200Hz (fixed)

Variable 0 - +18dB

20A x 1

6-5/8"

220W x 4

300W X 4

600W X 2

2 Ohm Stereo
4 Ohm Mono Bridged

0.01%

9Hz-50kHz

105dB

90dB

125+

40Hz-150Hz

200Hz (fixed)

Variable 0 - +18dB

40A x 1

11"

Notes