INTER-M A-60 User Manual

A-60/120 Public Address Amplifier

A-60

PUBLIC ADDRESS AMPLIFIER

MIC 1

MIC 2

MIC 3

AUX 1

AUX 2

BASS

TREBLE

MASTER

+3

0

-3

-7

-10

PROT

-14

POWER

MIN MAX

MIN MAX

MIN MAX

MIN MAX

MIN MAX

-12dB +12dB

-12dB +12dB

MIN MAX

ON

OFF

Contents

Contents

Welcome

Warning.........................................................................................................................................1

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

Installation

Environment....................................................................................................................................2

Important Safety Instructions.............................................................................................................2

Features............................................................................................................................................3

Accessories.....................................................................................................................................3

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

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

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

Connecting Speakers.....................................................................................................................6

Applications ....................................................................................................................................7

Block Diagram ................................................................................................................................8

Specifications ..................................................................................................................................9

Service

Procedures....................................................................................................................................10

Schematic.....................................................................................................................................10

Parts List .......................................................................................................................................10

Variations and Options ...............................................................................................................10

Warranty .......................................................................................................................................10

1

A-60/120

PUBLIC ADDRESS 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,
and we are delighted you have purchased one of our products.

We sincerely trust this product will provide years of satisfactory service, but if anything is not to your complete
satisfaction, we will endeavor to make things right.

Welcome 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.

DO NOT REMOVE COVER (OR BACK).

NO USER-SERVICEABLE PARTS INSIDE.

REFER SERVICING TO QUALIFIED SERVICE PERSONNEL.

WARNING

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

*Do not install this equipment in a confined space such as a book case or similar unit.
*The apparatus shall not be exposed to dripping or splashing and no objects filled with liquids, such vases, shall be placed on the apparatus.
*Worded: “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.”

This symbol is intended to alert the user to the
presence of uninsulated “dangerous voltage” within
the product’s enclosure that may be of sufficient
magnitude 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.

2

A-60/120

PUBLIC ADDRESS AMPLIFIER

Unpacking

Although your A-60/120 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,
setup and operation.

As with most electronic devices, we strongly recommend you retain the original packaging. In the unlikely event
the product must be returned for servicing, the original packaging (or reasonable equivalent) is required.

Installation

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 apparatus.
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
apparatus 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

S3125A

3

A-60/120

PUBLIC ADDRESS AMPLIFIER

Features

Features

- HIGH POWER, LOW DISTORTION

60W (A-60) or 120W (A-120) of RMS power, with less than 1% THD.

- VERSATILE AND EASY TO USE

Three Mic inputs, two Aux Inputs.

- PRIORITY MUTING

Mic1 input mutes other inputs when in use.

- FLEXIBLE DESIGN

Mono 4Ω or 70V/100V High-Impedance Outputs.

- TONE CONTROL

Separate Bass and Treble controls to tailor your sound.

Accessories

One detachable AC power cord is provided for use with this product.

Operation

Operation

Make certain that speakers and input sources are properly connected before switching on.

Keep volume levels turned down before switching on.

NOTE: The system’s operation is delayed by approximately three seconds after pressing the power switch. This is

due to the built-in protection circuitry, designed to protect speakers and other system components.

4

A-60/120

PUBLIC ADDRESS AMPLIFIER

Front Panel

Front Panel

1. BASS AND TREBLE CONTROLS

These knobs provide continuous control of the high and low frequency response, by adding up to 12dB of cut
(decrease) or boost (increase).

2. PROTECTION INDICATOR

This LED indicates the state of the amplifier’s protection circuitry. When the Protection LED is on (illuminated),
the protection circuitry is active, indicating that the unit is not operating normally. This is typically due to
overheating or power limiting. Please check the Input and Output condition of the amplifier.

3. OUTPUT LEVEL DISPLAY

This six-segment LED meter indicates the amplifier’s output level in RMS.

4. MIC VOLUMES 1-3

These knobs provide continuous control of the volume of Mic Inputs 1-3.

5. AUX VOLUME 1-2

These knobs provide continuous control of the volume of Aux Inputs 1 and 2.

6. MASTER VOLUME

This knob provides continuous control of the overall volume of the A-60/120 output.

7. POWER SWITCH

Pressing this switch turns the unit on, as indicated by the Power LED above the switch. Pressing it again turns
the unit off.

PUBLIC ADDRESS AMPLIFIER

A-60

PROT

-14

MIN MAX

MASTER

MIN MAX

MIC 2

POWER

MIN MAX

MIC 1

MIN MAX

MIC 3

-12dB +12dB

TREBLE

MIN MAX

AUX 1

MIN MAX

AUX 2

-12dB +12dB

BASS

-10

-7

-3

0

+3

ON

OFF

7

6

1

3

2

5

4

5

A-60/120

PUBLIC ADDRESS AMPLIFIER

Rear Panel

Rear Panel

1. AC POWER

Connect this cable to your AC outlet.

2. AUX INPUTS 1-2

These inputs are used for connecting line-level sources, such as CD, tuner or cassette deck.

3. SPEAKER OUTPUT TERMINALS

These terminals are used to connect speakers to the unit. You may select either 4Ω conventional operation, or
High Impedance operation at either 70V or 100V.

4. MIC 1,2,3 INPUTS

These 1/4" phone jacks accept a standard mic-level input. Input impedance is 600W, and input sensitivity is

0.6mV.

5. PRIORITY MUTE LEVEL

When Mic Input 1 is active, it mutes all other input signals (priority muting). When priority muting is in effect,
this control is used to set the amount of attenuation (how much muting) is applied to the other inputs when a
signal is present on Mic Input 1. The amount of attenuation can range from very little to complete muting..

PUSH PUSH PUSH

12

345

AUX 1AUX 2

L

R

L

R

MIC 2MIC 3 MIC 1

MIC 1 MUTE

MIN

MAX

WARNING;

~

AC INPUT

230V 50Hz, 75W

MODEL NO. A-60

PUBLIC ADDRESS AMPLIFIER

TO REDUCE THE RISK OF ELECTRIC SHOCK,

DO NOT EXPOSE THIS EQUIPMENT TO RAIN OR MOISTURE.

C

70V(83 )

100V(165 )

OM

AVIS;

RISQUE DE CHOC ELECTRIQUE NE PAS OUVRIR.

CAUTION;

TO REDUCE THE RISK OF ELECTRIC SHOCK,

DO NOT REMOVE COVER. NO USER SERVICEABLE PARTS INSIDE.

OC03OC03

0210

S

N

www.inter-m.com

REFER SERVICING TO QUALIFIED SERVICE PERSONNEL.

MADE IN KOREA

4

6

A-60/120

PUBLIC ADDRESS AMPLIFIER

Connecting Speakers

Connecting Speakers

Before connecting speakers to your A-60/120 unit, be sure to disconnect the AC power cable. Make certain that
the total impedance is not less than the rated impedance indicated.

For 4Ω low-impedance speakers, connect in parallel, with the positive (+) connectors to the 4Ω terminal and the
negative (-) connectors to the COM terminal. See Figure below.

For high-voltage distributed systems, connect with matching transformer to either 70V or 100V terminals, as per
Figures below. Be certain that the total impedance does not equal less than the rated impedance.

FOR 4Ω TERMINAL

FOR 70V TAP TERMINAL FOR 100V TAP TERMINAL

7

A-60/120

PUBLIC ADDRESS AMPLIFIER

Applications

Applications

PUSH PUSH PUSH

AUX 1AUX 2

L

R

L

R

MIC 2MIC 3 MIC 1

MIC 1 MUTE

MIN

MAX

WARNING;

~

AC INPUT

230V 50Hz, 75W

MODEL NO. A-60

PUBLIC ADDRESS AMPLIFIER

TO REDUCE THE RISK OF ELECTRIC SHOCK,

DO NOT EXPOSE THIS EQUIPMENT TO RAIN OR MOISTURE.

C

70V(83 )

100V(165 )

OM

AVIS;

RISQUE DE CHOC ELECTRIQUE NE PAS OUVRIR.

CAUTION;

TO REDUCE THE RISK OF ELECTRIC SHOCK,

DO NOT REMOVE COVER. NO USER SERVICEABLE PARTS INSIDE.

OC03

0210

S

N

www.inter-m.com

REFER SERVICING TO QUALIFIED SERVICE PERSONNEL.

MADE IN KOREA

4

CASSETTE DECK

CD PLAYER

SPEAKERS

MIC

MIC

MIC

8

A-60/120

PUBLIC ADDRESS AMPLIFIER

Block Diagram

Block Diagram

9

A-60/120

PUBLIC ADDRESS AMPLIFIER

Specifications

Specifications ..............................................................

0dB=0.775Vrms

- ELECTRICAL

Rated Output/Impedance.........................................................A-60: 15.5V/4Ω, 70V/81.6Ω, 100V/166.7Ω

..............................................................................................A-120: 21.9V/4Ω, 70V/40.8Ω, 100V/83.3Ω

Frequency Response (±3dB).......................................................................................................80Hz~16kHz

T.H.D........................................................................................................................................Less than 1%

S/N

Mic ..................................................................................................................................Better than 50dB

Aux..................................................................................................................................Better than 75dB

Input Sensitivity/Impedance

Mic Input 1-3 ................................................................................................................. -60dB/600Ω, Bal

Aux 1 Input................................................................................................................ -10dB/10kΩ, Unbal

Aux 2 Input ................................................................................................................. +3dB/10kΩ, Unbal

Tone Control

Treble (10kHz) ................................................................................................................................±12dB

Bass (100Hz) ..................................................................................................................................±12dB

- GENERAL

Power Source ................................................................................100–120VAC or 220–240VAC; 50/60Hz

..............................................................(Supplied AC mains transformer depends on country requirements)

Power Consumption.....................................................................................................................A-60: 75W

..............................................................................................................................................A-120: 105W

Weight ..........................................................................................................................A-60: 8.9kg/19.6lb

.................................................................................................................................A-120: 10.3kg/22.7lb

Dimensions..........................................................420(W) x 88(H) x 320(D)mm/16.5(W) x 3.5(H) x 12.6(D)in

* Specifications and design subject to change without notice.

10

A-60/120

PUBLIC ADDRESS AMPLIFIER

Service

Service

Procedures

Ensure the problem is not related to operator error, or system devices that are external to this unit. 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
manual.

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(in Korea or the
USA) or the authorized Inter-M Distributor for your specific country or region.

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.

1 EAST BEACON LIGHT LANE CHESTER, PA USA 19013-4409
TEL : [phone], FAX : [phone]
Home Page : http://www.inter-m.net, E-mail : [e-mail]

INTER-M Corporation

SEOUL OFFICE:653-5 BANGHAK-DONG, DOBONG-KU, SEOUL, KOREA
TEL : [phone]~8, FAX : [phone]
Home Page : http://www.inter-m.com, E-mail : [e-mail]

December 2005 9007103811 A

MADE IN KOREA