Inter-m MA-103 Operation Manual

Operation Manual

Digital Amplifier

MA-103

DIGITAL AMPLIFIER

Welcome

Welcome

A personal welcome to you from the management and employees of Inter-M

All of the co-workers here at Inter-M are dedicated to providing excellent products with inherently good value,
a

nd we are delighted you have purchased one of our products.

W

e sincerely trust this product will provide years of satisfactory service, but if anything is not to your complete

s

atisfaction, we will endeavor to make things right.

W

elcome to Inter-M, and thank you for becoming part of our worldwide extended family!

RISK OF ELECTRIC SHOCK

DO NOT OPEN

CAUTION

CAUTION: TO REDUCE THE RISK OF ELECTRIC SHOCK.

D

O NOT REMOVE COVER (OR BACK).

NO USER-SERVICEABLE PARTS INSIDE.

R

EFER SERVICING TO QUALIFIED SERVICE PERSONNEL.

ATTENTION : RISQUE DE CHOC ELECTRIQUE

NE PAS QUVRIR

WARNING

To prevent fire or shock hazard, do not
expose the unit to rain or moisture.

*WARNING FOR YOUR PROTECTION PLEASE READ THE FOLLOWING-WATER AND MOISTURE: Unit should not be used near

water(e.g. near a bathtub, washbowl, kitchen sink, laundry tub, in a wet basement, or near a swimming pool, etc). Care should be taken so
than objects do not fall and liquids are not spilled into the enclosure through openings.

*CLASS 2 WIRING (Adjacent to speaker terminal): The speaker output of this apparatus can exceed 10 Watts and could be a shock injury.

connection to speakers should be performed by a skilled person.
*Do not install this equipment in a confined space such as a book case or similar unit.
*Warning : To reduce the risk of fire or electric shock, do not expose this apparatus to rain or moisture and objects filled with liquids, such as

vases, should not be placed on this apparatus.
*This apparatus shall be connected to a mains socket outlet with a protective earthing connection.
*

To completely disconnect this apparatus from the AC mains, disconnect the power supply cord plug from the AC receptacle.
*

The mains plug of the power supply cord shall remain readily accessible.

CAUTION

*These servicing instructions are for use by qualified service personnel only. To reduce the risk of electric shock, do not perform any servicing

other than that contained in the operating instructions unless you are qualified to do so.

NOTE
*This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to Part 15 of the FCC Rules. These limits

are designed to provide reasonable protection against harmful interference when the equipment is operated in a commercial environment. This

equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the instruction manual, may

cause harmful interference to radio communications. Operation of this equipment in a residential area is likely to cause harmful interference in

which case the user will be required to correct the interference at his own expense.

This symbol is intended to alert the user to the pres­ence of uninsulated “dangerous voltage” within the
p

roduct’s enclosure that may be of sufficient magni-

tude to constitute a risk of electric shock to persons.

This symbol is intended to alert the user to the pres­ence of important operation and maintenance (ser­vicing) instructions in the literature accompanying
the appliance.

Caution: To prevent electric shock do not use this (polarized) plug

with an extension cord, receptacle or other outlet unless the
blades can be fully inserted to prevent blade exposure.

Attentions: Pour prévenir les chocs électriques ne pas utiliser cette

fiche polarisée avec un prolongateur, une prise de courant
on une autre sortie de courant, sauf si les lames peuvent
étre insérées à fond sans en laisser aucune partie à dé­couvert.
Pour deconnecter completement l’appareil du reseau d’al­imentation. deconnecter le cordon d’alimentation de la
prise murale.
La prise du reseau d’alimentation doit demeurer aisement
accessible.

DIGITAL AMPLIFIER

1

MA-103

Contents

Contents

Unpacking....................................................................................................................................... 2

Installation

E

nvironment....................................................................................................................................2

I

mportant Safety Instructions.............................................................................................................2

Features.

.......................................................................................................................................... 3

Package and accessory includes.................................................................................................3

Operation........................................................................................................................................ 3

Front Panel...................................................................................................................................... 4

Rear Panel....................................................................................................................................... 5

Applications.................................................................................................................................... 8

Block Diagram.............................................................................................................................. 10

Specifications................................................................................................................................ 11

Service

Procedures....................................................................................................................................13

Schematic.....................................................................................................................................13

Parts List....................................................................................................................................... 13

Variations and Options............................................................................................................... 13

Warranty....................................................................................................................................... 13

DIGITAL AMPLIFIER

2

MA-103

Installation

Unpacking

Unpacking

A

lthough your MA-103 is neither complicated nor difficult to operate, we recommend you take a few minutes
to read this brief manual and familiarize yourself with the important information regarding product features,
s

etup and operation.

A

s with most electronic devices, we strongly recommend you retain the original packaging. In the unlikely
e

vent the product must be returned for servicing, the original packaging (or reasonable equivalent) is

required.

Installation

Environment

Never place this product in an environment which could alter its performance or reduce its service life. Such
environments usually include high levels of heat, dust, moisture, and vibration.

IMPORTANT SAFETY INSTRUCTIONS

1. Read these instructions.

2. Keep these instructions.

3. Heed all warnings.

4. Follow all instructions.

5. Do not use this apparatus near water.

6. Clean only with dry cloth.

7. Do not block any ventilation openings. Install in accordance with the manufacturer’s instructions.

8. Do not install near any heat sources such as radiators, heat registers, stoves, or other apparatus (including

amplifiers) that produce heat.

9. Do not defeat the safety purpose of the polarized or grounding-type plug. A polarized plug has two blades

with one wider than the other. A grounding type plug has two blades and a third grounding prong. The
wide blade or the third prong are provided for your safety. If the provided plug does not fit into your outlet,
consult an electrician for replacement of the obsolete outlet.

10. Protect the power cord from being walked on or pinched particularly at plugs, convenience receptacles,

and the point where they exit from the apparatus.

11. Only use attachments/accessories specified by the manufacturer.

12. Use only with the cart, stand, tripod, bracket, or table specified by the manufacturer, or sold with the appa-

ratus. When a cart is used, use caution when moving the cart/apparatus combination to avoid injury from
tip-over.

13. Unplug this apparatus during lightning storms or when unused for long periods of time.

14. Refer all servicing to qualified service personnel. Servicing is required when the appa-

ratus has been damaged in any way, such as power-supply cord or plug is damaged,
liquid has been spilled or objects have fallen into the apparatus, the apparatus has been
exposed to rain or moisture, does not operate normally, or has been dropped.

S3125A

DIGITAL AMPLIFIER

3

MA-103

Features

Features

- COMPACT DESIGN

Easy to install and operate with compact design of 1U size and functions.

- DIGITAL AMPLIFIER CIRCUIT

T

ake up the Digital Amplifier Circuit with High efficiency of the rated power 30W, High reliability, Low weight

and Low temperature.

- SUPPLY POWER BY SMPS

Take up SMPS (Switching Mode Power Supply) for Low electric power and Low weight.

- VARIOUS INPUT & ADDITIONAL FUNCTIONS

Configured 3 channel inputs and various reception of inputs are available by 3.5mm 3P EURO input, 6.3Φ &

3.5Φ Phone Jack, RCA cable.
More convenient use via TEL-IN and Priority function.

- TONE CONTROL FUNCTION

Separate Bass(300Hz) and Treble(10kHz) controls to tailor your sound. Easy to control the tone due to user
frequency which is including bass and treble.

- PRIORITY BROADCAST FUNCTION

Adopted the Priority broadcast function that can control other input signal by TEL IN & INPUT 1 input signal.
(TEL IN >> INPUT 1 >> INPUT 2 = INPUT 3)

Operation

Operation

1. Before you plug the power cord to AC outlet, please set the power switch OFF, Tone Control center, and volume
level minimum.

2. Please make sure the speakers and input jacks are properly connected before turn the power switch on.

3. Be sure the AC power is correct voltage before you plug into the power cord. (AC 100-240V)

4. Please push the power switch, then the power input LED is on and the unit will be operated.

5. Please use your own with adjustment the volume using each input volume and master volume, the tone using
the tone control.

Package and accessory includes

Package and accessory includes

1. Euro terminal block (3.5mm pitch) 3P x 2EA

2. Euro terminal block (5.08mm pitch) 7P x 1EA

3. User manual x 1EA

DIGITAL AMPLIFIER

4

MA-103

Front Panel

Front Panel

1. POWER SWITCH

This switch turns the power on and off. Green LED is on when the amplifier is active and powered.

2. LED INDICATES ACTIVE STATUS OF AMPLIFIER PROTECTION NETWORK

LED indicates the operation status of protection network inside of equipment. Once the protection circuit
is operated, LED is turned on and the output is blocked.

3. MASTER VOLUME CONTROL

Control equipment that control overall volume of audio signals adjusted by each input audio volume con­trol equipment. Clockwise turning will increase the audio volume.

4. TONE CONTROL

These control the bass(300Hz) and treble(10kHz) of the main output signal by ±10dB.

5. AUX 3.5Φ PHONE JACK INPUT TERMINAL

The unbalance input terminal to connect with external devices capable to connect with devices such as
mobile phones, MP3 etc.

6. INPUT VOLUME CONTROL

The input volume control by which volume can be adjusted fit to each channel of INPUT 1, 2, 3.

POWER

I

NPUT1 INPUT2 INPUT3 AUX BASS TREBLE

VOLUME

PROTECT

MA

103

MIXING AMPLIFIER

6

5 2

4

3 1

3.5mm

DIGITAL AMPLIFIER

5

MA-103

Rear Panel

Rear Panel

1. SPEAKER OUTPUT TERMINAL

This is the terminal for speakers. 8, 70V(166), 100V(333) cannot be used at the same time. It may
cause overload and malfunction.
※ Connecting Speakers

Before connecting speakers to MA-103 unit, be sure to disconnect the AC power cable.

LINE LINE

H

IGHLOW

IMPEDANCE

8

1 2 8 7 4

9 6 3 5

8

8Ω

8Ω SPEAKER 사용 시

HIGH

LOW

IMPEDANCE

For100V TERMINAL

For 8 TERMINAL

For 70V TERMINAL

8

HIGH

LOW

I

MPEDANCE

8

HIGH

LOW

I

MPEDANCE

DIGITAL AMPLIFIER

6

MA-103

※

NOTE: 1. Make certain that the total impedance is not less than the rated impedance indicated. (LOW-

8

, 70V-166, 100V-333)

2. Please make sure not to use 8, 70V, 100V terminals simultaneously.

3. Upon using 100V(333),70V(166), please set impedance selection switch to HIGH, and for
8  speaker, set impedance selection switch to LOW.

※N

o sound is output upon the impedance selection switch is not set properly, thus please be careful

u

pon install or using it.

2. IMPEDANCE SELECTION SWITCH

This is LOW impedance or HIGH impedance selection switch. In case to use 8Ω speaker select LOW,
and for 166Ω or 333Ω speaker, please select HIGH. (there will be no speaker output if the setting is not
proper)

3. INPUT 1 MIC INPUT TERMINAL (6.3Φ, PHONE JACK, BALANCED)

Phone Jack terminal that inputs Mic signal to INPUT 1.
<6.3Φ, Phone Jack>

4. INPUT 1 TERMINAL (3P EURO)

This is the balance input terminal of INPUT 1. It can use Mic and line input.
<EURO Terminal>

(Balanced Cable)

Use 3.5mm 3P Euro terminal.

5. LINE / MIC INPUT TERMINAL & INPUT SELECTION SWITCH (INPUT 1)

Switch for selecting Mic and line signal input. The usage of input terminal differs from respective input
selection switch.

- LINE: Use for line input.

- MIC: Use for ordinary Dynamic or 6.3Φ Phone Jack mic input.

6.3mm

LINE LINE

DIGITAL AMPLIFIER

7

MA-103

6

. INPUT 2 TERMINAL (3P EURO)

B

alance input terminal of INPUT 2. Mic and line input can be used.

<

EURO Terminal>

(

Balanced Cable)

Use 3.5mm 3P Euro terminal.

7. LINE / MIC INPUT TERMINAL & INPUT SELECTION SWITCH (INPUT 2)

Switch for selecting Mic and line signal input. The usage of input terminal differs from respective input
selection switch.

-LINE: Use for LINE input

-MIC : Use for ordinary Dynamic MIC input

8. INPUT 3 (RCA INPUT)

The unbalance input terminal that connects external devices. It can be connected source devices such as
computer, CD, DVD etc.

(Unbalanced Cable)
Use stereo audio pin cable.

‘Y’ cable is needed when connecting to computers.

(Unbalanced Cable)
Use stereo audio pin Y.

9. TEL IN TERMINAL

This is the audio signal input terminal of the Switch Board. Once a signal is input to terminal the output
of other input signal is to be reduced in accordance with priority, and TEL IN input signal is to be output.
(TEL IN >> INPUT 1 >> INPUT 2 = INPUT 3)

LINE LINE

3.5ø

DIGITAL AMPLIFIER

8

MA-103

LINE LINE

HIGH

LOW

IMPEDANCE

8

PC

or

PHONE

8Ω

SPEAKER

CD PLAYER

POWER

INPUT1 INPUT2

INPUT3

AUX BASS

TREBLE

VOLUME

PROTECT

MA

103

MIXING AMPLIFIER

TELEPHONE

INTERFACE

MIC

MIC

MIC

Using LOW IMPEDANCE SPEAKER

Applications

Applications

DIGITAL AMPLIFIER

9

MA-103

L

INE LINE

H

IGHLOW

IMPEDANCE

8

PC

or

PHONE

100V/333Ω

SPEAKER

70V/166Ω

SPEAKER

CD PLAYER

TELEPHONE

INTERFACE

MIC

MIC

MIC

P

OWER

I

NPUT1 INPUT2

INPUT3

A

UX BASS

TREBLE

V

OLUME

P

ROTECT

MA

103

MIXING AMPLIFIER

Using HIGH IMPEDANCE SPEAKER

DIGITAL AMPLIFIER

10

MA-103

MIC1/AUX1

TEL IN

MUTE

(6.3φ)

gain selector

gain selector

PROTECT LED

SELECTOR

IMPEDENCE

MUTE

(3.54φ)

-15dBu/2kΩ

PHONE JACK

HATEL IN

0dBu/5kΩ

COM

G

-

+

-15dBu/2kΩ

-60dBu/2kΩ

MIC1/AUX1

LIMITER

BA

BPF

±8dB

SA

BA

HA

HA

HA

POWER LED

-60dBu/2kΩ

MIC1

G

-

+

MASTER VOL

VOL 3

VOL 2

VOL 1

G

-

+

PA

-15dBu/20kΩ

AUX

-15dBu/2kΩ

-60dBu/2kΩ

MIC2/AUX2

POWER S/W

AC INPUT

TONE CONTROL

COM

8ohm

70V

100V

SMPS

+26V

SLVTR

TS

FUSE

Block Diagram

Block Diagram

DIGITAL AMPLIFIER

11

MA-103

Specifications

Specifications

※Design and specification are subject to be changed for the improvement of product

quality without pre notice.

MA - 103

Rated Output Power 30W

Speaker Output Power / Impedance

15.5V/8Ω, 70V/166Ω, 100V/333Ω

Input Sensitivity
/ Impedance

MIC (BALANCE) -60dBu/2kΩ

LINE (BALANCE) -15dBu/2kΩ

RCA (UNBALANCE) -15dBu/20kΩ

3.5Φ PHONE JACK (UNBALANCED)

-15dBu/2kΩ

TEL IN 0dBu/5kΩ

LOW IMPEDANCE (8Ω) LINE,RCA,TEL IN
Frequency Response (1W,±3dB)

200Hz ~ 18kHz

LOW IMPEDANCE (8Ω)
MIC Frequency Response (1W,±3dB)

200Hz ~ 13kHz

T.H.D - 1/3Pwr Less than 0.5%

S/N

MIC Better than 55dB

LINE, TEL IN, Better than 75dB

RCA, 3.5Φ PHONE JACK Better than 75dB

Tone Control

BASS(300Hz) ±10dB

TREBLE (10kHz) ±10dB

Operating Temperature

-10℃ ~ +40℃

Power Source AC 100 ~ 240V, 50/60Hz

Power Consumption 10.5W(1/8W)

Weight (SET) 1.5kg/3.3lb

Dimensions (SET)

210(W) x 44(H) x 180(D)mm/

8.27(W) x 1.73(H) x 7.09(D)in

DIGITAL AMPLIFIER

12

MA-103

※DIMENSIONS

210

209.6

44 180

DIGITAL AMPLIFIER

13

MA-103

Service

Service

Procedures

T

ake steps to insure the problem is not related to operator error or other products within the system. Information
provided in the troubleshooting portion of this manual may help with this process. Once it is certain that the
problem is related to the product contact your warranty provider as described in the warranty section of this
m

anual.

Schematic

A Schematic is available by contacting your warranty provider.

Parts List

A Parts List is available by contacting your warranty provider.

Variations and Options

Variations and Options

Variations

Products supplied through legitimate sources are compatible with local AC power requirements.

Options

No optional items are available for this product.

Warranty

Warranty

Warranty terms and conditions vary by country and may not be the same for all products. Terms and conditions
of warranty for a given product may be determined first by locating the appropriate country which the product
was purchased in, then by locating the product type.

To obtain specific warranty information and available service locations contact Inter-M directly or the
authorized Inter-M Distributor for your specific country or region.

MADE IN KOREA

February 2017 141392

Inter-M, Ltd. (Korea) began operations in 1983.

Since then, Inter-M has grown to become one of the largest manufacturers
of professional audio and commercial sound electronics equipment in the world.

Inter-M has gained worldwide recognition for its own branded products,
as well as private label manufacturing of electronics sold under other names (OEM).

The company is no longer just a Korean company, but rather a global company
that is truly international in scope, with factories and offices in Korea and China,
and sales and marketing operations located in Japan, Europe, and the U.S.A.

With more than 850 employees around the globe,
Inter-M is well-poised for further growth and expansion.

Inter-M Americas, INC.

5666 CORPORATE AVE. CYPRESS, CA 90630
TEL : [phone], FAX : [phone]
Home Page : http://www.inter-m.net, E-mail : [e-mail]

Inter-M Corporation

SEOUL OFFICE : 719, DOBONG-RO, DOBONG-GU, SEOUL, KOREA
TEL : [phone]~8, FAX : [phone]
Home Page : http://www.inter-m.com, E-mail : [e-mail]