Boss Audio Systems MR250.4, MR400.2 User Manual

User's Manual

2

CHANNEL

BRIDGEABLE

MOSFET

MARINE

POWER

AMPLIFIER

4

CHANNEL

BRIDGEABLE

MOSFET

MARINE

POWER

AMPLIFIER

---

o~s

USER'S

MANUAL

~

Two Channel

MR400.2

High

Power

MOSFET

Marine

Audio

Amplifier

Four

Channel

MR250.4

High

Power

MOSFET

Marine

Audio

Amplifier

Congratulations

on

your

purchase

of

a

:lO~:S

Marine

oWIlX'n~

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

!9.~

Marine

your choice for

marine audio entertainment!

page

CONTENTS

2

Introduction

2

What

is

included?

3

Features

3

About 2 Ohm

operation

4

General

precautions

4 Protection

circuitry

5 Installation

precautions

5

Fuses

6

Mounting

the

amplifier

6

Connecting

the

amplifier

8

Low

level

input

wiring

9 High level

input

wiring

10

Power

and

speaker

wiring

2 Channel

Amplifier

12

Power

and

speaker

wiring

4 Channel

Amplifier

14

Troubleshooting

5

Specifications

MMne

MOSFET A.rnpl1fier Us.er's Manual -

poge

1

Introduction

With the

~~

Marine

MOSFET amplifier series, we are introducing two

new amplifiers, designed specifically for marine audio installations. This new series includes a 2-channel amplifier and a 4-channel amplifier.

All

iiO~S

Marine

models feature both highp;"S's and low pass crossovers. For further flexibility

in

the use of a

subwoofer. a variable bass

boost

control has been included.

You

can control the subwoofer level with the remote level control module.

These

!9~

Marine

amplifiers are constructed using a special corrosion resistant coating on the printed circuit board

to

prevent damage from the

high humidity

of

the marine

environment.

•

~

Marine

understands that

amplifiers are placed

in

many different

kinds

of

installations, so we have also

Included

an

Input sensitivity control 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 player.

•

Marine

amplifier

•

HIgh

input

wire

with

connector

•

Four

(4)

mounting

screws

Features

Your new

!9~1

Marine

amplifier

features the following:

• Class

A-B

operation

•

Bridgeable

outputs

•

TriMode

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

and

fixed

high

pass

crossovers

• Variable

bass

boost

(0

to

+18dB)

• Exclusive

protective

coating

on

PC

board

to

provide damage

from

humidity

•

Gold

plated

RCA

low

level and

high

level

inputs

• LED

power

and

protection

indicators

• Silver

anodized

heatsink

•

Remote

subwoofer

level

control

About 2 Ohm

operation

Your'30~S

Marine

amplifier has be€n

desig'n~70

operate efficiently 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 100t-fz)

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

outpul

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.

Mu

.....

ne

MOSFET ArnpllflOJ

User's

Manual -

pagf:!'

3

Manno MOSFET Ampllnlll' U

.....

s Manual - page 2

General

precautions

Before installing

and

l/sing

YO(1r

new

3\)~

Marine

amplifier,

please

be-

~~

familiar

with

a'll

the

informa-

tion

contained

in

this

mal1ua/~

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 amplifier,

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 cord and send the amplifier to your local dealer

or

service center

as

soon as

possible.

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.

Martnc MOSFET Ampllftor User's

Manual·

page 4

Protection

Circuitry

This amplifier incorporates special protection circuitry

Which

will disable

the amplifier if any

of

the following

should occur:

• Input overload

• Short circuit

• Extremely high temperatures

If any of these conditions

Is

detected,

the amplifier will

go

into a selfpreservation mode, and the PROTECT LED on the model number badge

on

top

of the amplifier will be illuminated.

What should I

do

if

my

amplifier

PROTECT LED

is

illumInated?

If

you observe that the PROTECT

LED

is

on, please check the system carefully to determine what has caused the protection

c1rcuit

to

engage.

To

reset the amplifier when it is in PROTECT mode, turn the power off to the system (usually

by

turning off the head unit or other signal source which feeds the amplifier) and then turn it on again.

If the amplifier has shut down due to thermal overload. you should first allow it

to

cool down before restarting.

If the shut

down

was due

to

either

an input overload or a short circuit, be sure to correct these conditions before attempting

to

power

up

the amplifier

again.

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 within the amplifier to prevent damage, especially in

an

accident.

Do not mount this amplifier so thai wire connections are unprotected,

in a pinched condition, in contact with any metal surfaces

in

your marine

vessel,

or

likely to be damaged by

nearby objects.

Before making

or

breaking power

connections

in

your system,

disconnect the marine vessel 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.

Fuses

Power fuses protect both the amplifier and the electrical system of your

car

from fault conditions. If you must replace a fuse

in

your Marine amp,

use

a fuse

of

exactly the same type and

rating. Us,ng a different type

or

rating

of

fuse may result

in

damage to your

amp or marine vessel

or cause a fire.

MarIne MOSFET Amplifier User's Manual - page 5

Mounting

the

amplifier

1. Find a suitable location

in

the marine

vessel

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

surlace.

If

the

mounting

surlace

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

surlace

securely uSing screws.

Connecting

the

amplifier

Before dOing

<my

wiring, look through

this

marual

and

identify the

diagrams

to

follow for power.

input

and speaker

connections

for

your

particular

installation.

Be

sure you

understand

all

the connections before you proceed.

1. Connect the

power

ground

terminal

to

tr.e

closest

point

on

the

chassis

of

the

marine

vessel. Keep

tris

ground

wire

to

less than 39" (100 em) h length.

Use

8

gauge

(or heavier) wire.

2.

Connect

the remote terminal

10

the

remote

output

of

the head

unit

uSing

16

gauge

(or heavier) wire.

3. Connect an

empty

fJse holder within

18" (45 em)

of

the car battery. and run

8 gauge (or heavier)

cable

from

this

fuse

to

the

amplifier

location.

4. Check that trfJ fuse holder is empty.

Then COllnect the fuse

holder

to

the

"BAn

+.

connection

on

the amplifier.

5.

If multip:e 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 #0

or

#2

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.

7. Insert tuse(s)

into

the

battery

fuse

holder(s).

8.

Recheck

all

connections

before

powering

up

the

amplifier.

9.

Sel

all level

controls

to

min,imum

position,

and

set all

crossover

controls/switches

to

the desired

frequency

poillts.

10.

Power

up the

head

unit

and

the

amplifier. Then

s~t

the

volume

control

on

the

nead 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.

Don't

.misuse

the

level

cont:rol_!

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

nol

adiust

this

input

level

to

maximum

unless

your

input

level

requires il.

Ignoring

thElse

instructions will result

in

an input overload

to

the amplifier,

and

excessive

al:Jdio

cjistortion. It can also cause the protectiolfl circuit to

.engage.

Marine MOSFET Amplifier User's

Manual·

page 7

Marine MOSFET

Ampli~Ol

Usel'~

Manual·

page 6

(1])

(

Low

Level

Input

Wiring

High

Level

Input

Wiring

Low-level (RCA)

input

wiring is preferred

for

best audio performance, Always use

The high level input(s) should only be used when your head unit lacks RCA outputs,

a high-quality RCA cable for best audio pertormance.

If the RCA

outputs

are

not

present, connect

the

speaker outputs from the receiiver

to the high level input

connector

of the amplifier. Be sure

to

observe polarity to

NOTE: Do

not

connect

BOTH

the

high

!evel

and

low

level

inputs

from

your

avoid audio phase problems,

receiver

to

your

amplifier

at

the

same

time!

NOTE: Do

not

connect

BOTH

the

high

level

and

low

level

inputs

from

your

,

receiver

to

your

amplifier

at

the

same

timet

2-Channel

Amplifier

2-Channel

Amplifier

MR400.2

1"'"'

-----"

MR400.2

J

7

Optlonnl

remote

ulJwoofer

level conlrQI

(sold

~epamtelvl

To

Audio

Outputs

of

head

unit

or

signal

processor

IObO;;;:;z;x::)

I

l+

l~

R· R

...

Optional

remote

ubwoofcr

lellel

contro

(sold separately)

To

Speaker

Terminals

of

head

unit

4-Channel

Amplifier

Optlonal

remote

"ubwoofer

level

control

MR250.4

(sold separately)

4-Channel

Amplifiers

MR250.4

@

'\

!

TO FRONT

Audio

Outputs

To

Speaker

of

head

unit

or

10l:=J I

Terminals

signal

processor

of

head

unit

To

REAR

Audio

Outputs

of

headl

unil

or

signal

processor

~~

c.;:

;~

Optlonlll

remote

I

[]

subwooler

level

control

01

~

(sold se!l"arately)

1::Ic:::JCJC:::lt::lO

Ma"ne

MOSFET

AmpRfier

User's Manual·

p8ij8

8

Marlne MOSFET Amplifier User"s

Manual"

page

9

I

Et7

Q

poweA

Chassl$

groUf'ld

point

to

REMOTE

TURN-ON

tennlnal

01

head

unit

MINIMUM

SPEAKER

IMPEDANCE

40HMS

~

./'

Q

$

MINIMUM

SPEAKER

IMPEOANCE

4 OHMS

Power

and

Speaker

Wiring

2-Channel

Amplifier

MR400.2

Power

and

Speaker

Wiring

2·,Chanhel

Amplifie!i

"'11400.2

Two

Channel

R.IGHT

Speaker

Bridged

SPEAKER

IMPEDANCE

4-8 OHMS

$

Q

POW,liR

Ch.a;sls

ground

point

to

REMOTE

TURN-ON

18111'1

inal

0 r

head u ni

l

~

Q

LEFT

Speaker

Mode

ttl

o

CJ

c::J

FUSE

I

Batlery

I

ttl

Q

~I,.o,ll£l'n

Cha'"ssis

ground

point

to 'REMOTE

TllRN·ON

~

Q

SUBWOOFER

ttl

Mode

torm

lnal

of I'cad

unIt

Connecr the Negmive (-)

terminal

of

1M

speaker to

/he

o

c::J

CJ

R(-)

amplifier

terminal.

FUSE

I

Battery

I

COnnec!

the posJtlve (+)

terminal ofthe spooker 10 !he L(+)

amplifier

terminal.

Tri-mode operation allows you to connect this amplifier to a

pair-

of

main speakers

plus a sUlbwoofer 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 switch in the

FULL

position. Insert

h'igh

pass filter capacitors and a

low

pass fliller -nditJctor into the

wiring as

shown

below. Be sure to check the table at the bottom

of

this page

to determine the correct capacitor ar.d inductor values for the crossover frequency you wish

10 achieve,

Tri-Mode

LEFT

Speaker

HIgh

pass

filter

RIGHT

Spaaker

capacitors

o

c::::I

c::J

SP'EAKER

FUSE I

Ba

tte

ry

I

IMPEDANCE

80HMS

Component

values

for

6dB

Passive

Crossover

FREQUENCY INDUCTOR CAPACITOR 80 Hz

7.5mH

470uF

tOO

Hz

6.5mH

330uF

120 Hz

5.5mH

330uF

t50

Hz

4mH

220uF

Lowpass

filter Inductor

Marino MOSFET Amplifier

Users

Manual - page

10

Marine

MOsFET

AmplirJel USB(S

Manual-

page

11

Power

and

Speaker

Wiring

4-Channel

Amplifier

h

MR250.4

E:t)

Chassl.

ground

CH3

polnt

Sponker

to

REMOTE TURN'ON

CH4

o

Speaker

FUSE

l~atte~1

SPEAKER

IMPEDANCE

Connect rile Negative

(-J

terminal

of

Ihe RIGHT

4-8 OHMS

subwoofer to the CH4(-) amplifier tarmlnal.

RIGHT

Connact lhe Postive

(+)

terminal

of

!he RIGH

Subwooler

subwoofer 10 the CH3(+) amplifIer terminal.

atidged Mode

E:t)

o

Chnssfs

ground

poln!

LEFT

10

REMOTE TURN·ON

Subwoofer

terminal

01

head unit

o

D

c::J

FUSE

I

Battery

I

SPEAKER

IMPEDANCE

4-8 OHMS

Mmine MOSFET Amplifier User's Manual -

page'

2

terminal

ot head unit

Connecllhe

Negative

(-J

terminal

of

rhe LEFT

subwoofer

10

the CH2(·) amplifier terminal.

Connect the Pos/lVa

(+)

terminal

of

the

LEfT

subwoofer

10

the

CH1(+J

amplifier tarmlfl8.l.

Power

and

Speaker

Wiring

4-Channel

Amplifier

MR250.4

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.

Component

values

for

SPEAKER

6dB

Passive

Crossover

IMPEOANCE

elli

••

ls

ground

point

MINIMU

SPEAKER

IMPEDANCE

40HM9

SPEAKER

IMPEDANCE

80HMS

Marino MOSFET Amplltier User's Manual - P'lIIe

13

470uF 330uF 330uF 220uF

o

o 0

I

Battery

I

lo

REMOTE

nJRN-QN

term!nal

of

head

unit

7.5mH

6.5mH

5.5mH

4/111-1

FUSE

FREOUENCY INDUCTOR CAPACrrOR

80 Hz

100 Hz

120 Hz 150 Hz

80HMS

Tri~Mode

Troubleshooting

If

you experience operation or perionnance 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.

SYMPTOM

POSSIBLE

REMEDY

Amplifier

will

not

power

up.

Check to make sure you have a

good

ground connection.

Check that the Remote Input (Tum-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 ls not illuminated. If It

Is

lit. shut

off

the amplifier briefly.

and

(hen repower

It.

Protection

LE.D

comes

on

when

amplifier

is

powered

up.

Check for

short

clrcwts on speaker leads.

Tum

down the volume control on the head umt to prevent overdrlving.

Remote speaker leads, and reset the amplifier.

If the Protection LED

stil,

comes

on, then the ampllfTer Is faulty and needs servicing,

No

output.

Check that all fuses are

OK. Check that amplifier Is properly grounded. Check thaI the Remote Input (Tum·

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,

It

the hiss disappears, thel

plug

in the component

dn"vmg

the amplifier

and

unplug Its Inputs. If

thE

hiss disappears

a/

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.

Th

best

sUbjective s/gna/-to-noise ratio is achieved

In

this manner.

Try

/0

s

the head unit

as

high

8S

possible (I¥/lhout distortion)

and

the

amp

Inpu

level

as

low as possIble.

Squealing

noise

from

speakers.

Check for improperly grounded RCA Interconnects,

Distorted

sound.

Check that the Input Level

Contrails

set

to

match the signal level

of

the

head unit. Always try to set the Input Lavel

as

low

as possIble.

Clleck that all crossover frequencies

are properly set.

Check

for

short

circuits on the speaker leads.

Amplifier

gets

very

hot.

CllfICk that the minimum speaker Impedance

tor

the amp model Is correct.

Check thaI there

is

good

air circulatJon around the amp. In some

applications,

it

may

be

necessary to

add

and

extemal cooling

fan.

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 man'ne vessel chassis. Check that the RCA grounds are not shorted to the marine vessel chassis. Check that the head unit

is

properly grounded.

Specifications

MODEL

I\M$

POWER

into 4 Ohm5

'MAX

POWER

into 2 Ohms

BRIOGE.O

POWER

Into 4 Ohms

Min.

speak·e.

,impedance

THO

Frequency

response

Sl~na!·to-noi$e

r

...

tio

Channel

separation

Damping

factor

Crossover

range

low pa••

[high

pass

[Bass

Ibo'ost

IFuse

rating

i{;lil1lenslorfS:

(1,

1·3/4"

X 2-518;1

l<

...

)

Two

Chllnnel

Four Chenn'1l

MarIne

Amplifier

Marine

AmplifIer

MR400.2

MR.250.

125W

x2

100Wx4

400W x 2

250W x 4

SOOW

x 1

500W

x2

2 Ohm Stereo/4 Ohm

Mono

Bridged

------

0.01% 6Hz-50kHz 103dB

90dS

125+

35HZ-155Hz 200Hz (fixed)

0-

+1SdS

25A

x

10-31S'

0.01% 6Hz-50kHz 103dB

gOdS

125+

35Hz.-155Hz 200Hz (fixed)

o

-+18dS

15Ax2 13-1116'

All

specifications

subject

to

change

without

notice.

e

t

Maline MOSFET Amplifier

U..,,'.

Manual - p3ge

14

Marine MOSFET Amplifier

User'.

Manual·

page

15