Inter-m PAM-120, PAM-60 Operation Manual

PAM-60/PAM-120

Public Address Amplifier

Copyright 2004 Inter-M Corporation

PAM-60/PAM-120 Public Address Amplifier

Contents

Welcome ..................................................................................................................................... 3

Unpacking ............................................................................................................................... 3

Warnings .................................................................................................................................. 3

Operation................................................................................................................................. 5

Features ....................................................................................................................................... 6

Front Panel Controls.................................................................................................................... 7

Rear Panel Controls .................................................................................................................... 9

Installation of Speakers ............................................................................................................ 12

Connecting 4Ω or 8Ω Speaker Systems ............................................................................. 12

Connecting High-Voltage Distributed Speaker Systems................................................... 12

Applications .............................................................................................................................. 14

Specifications............................................................................................................................ 15

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PAM-60/PAM-120 Public Address Amplifier

Welcome

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

Thank you for purchasing this fine Inter-M product. All of us here at Inter-M are dedicated
to providing you with the highest quality products and the best value.

We sincerely trust this product will provide you with 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 a part of our worldwide extended
family!

Unpacking

Although your PAM-60 or PAM-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.

Warnings

Environment

Never place this product in an environment that could alter its performance or reduce its
service life. Such environments are usually characterized by high levels of heat, dust,
moisture, or vibration.

Safety

1. Read these instructions carefully.

2. Follow all instructions.

3. Keep all warnings.

4. Do not operate this apparatus near water.

5. Clean only with a damp cloth.

6. Do not block any of the ventilation openings.

7. Install only in accordance with the instructions in this manual.

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PAM-60/PAM-120 Public Address Amplifier

8. Do not install near any heat sources such as radiators, heat registers, stoves, or other
devices (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 is 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 it is attached to the apparatus.

11. Use only the attachments/accessories specified.

12. Use only with a cart, stand, tripod, bracket, or table specified, or sold with the
apparatus. When a cart is used, use caution when moving the cart/apparatus
combination to avoid overturning.

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.

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PAM-60/PAM-120 Public Address Amplifier

Operation

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

Keep volume levels at minimum gain before switching on.

NOTE: The system’s operation is delayed by approximately three seconds after pressing
the AC Mains power switch. This is due to the built-in protection circuitry, designed to
protect the speakers and other system components.

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PAM-60/PAM-120 Public Address Amplifier

PAM-60/PAM-120
Public Address Amplifier

Features

Modular Design

• Optional modules can be installed in multiple configurations for convenience and
ease of use. Choose the PAM-CDA (Compact Disc), PAM-T (AM/FM Tuner) or PAM-D
(Cassette Deck) modules to expand the PAM-60/120’s audio capabilities.

Individual Input Gain Controls

• Rear-panel gain controls for each input channel for total control of individual levels.

Speaker Select

• Six speaker select switches enable you to select any combination of up to five
speakers.

Selectable Priority Muting

• Switchable audio signal priority for Channels 1 and 2, Chime and Telephone input
over other input sources.

Telephone Input/Music-on-Hold

• Telephone input for connection with telephone system. Music-on-Hold function
available with optional PAM-T AM/FM tuner module.

Remote Control Input

• Individual speaker zones can be selected and chime can be operated by wired
remote control.

Announcement Chime

• Convenient four-tone chime for use with announcements.

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PAM-60/PAM-120 Public Address Amplifier

Front Panel Controls

1. Power Switch

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

2. Speaker Selector Switches

These switches are used to select output to any combination of up to five
individual speakers.

3. Chime Button

Pressing this switch activates the chime circuitry.

4. Master Volume

This rotary switch controls the overall output volume of the amplifier’s output
signal.

5. Tone Control

Individual Bass and Treble controls are used to cut (decrease) or boost (increase)
the lower and higher frequencies ±12dB.

6. Channel 1-6 Volume

Controls the individual volume levels of Channels 1-6.

7. 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.

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PAM-60/PAM-120 Public Address Amplifier

8. Output Level Display

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

9. Cassette Deck and CD Module Bay

This panel provides for installation of optional PAM-CDA (CD Player) or PAM-D
(Cassette Deck) Modules, via the unit’s internal connectors.

10. Tuner Module Bay

This panel provides for installation of optional PAM-T (AM/FM Tuner) Module, via
the unit’s internal connectors.

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PAM-60/PAM-120 Public Address Amplifier

Rear Panel Controls

1. Channel Inputs 1-6

These balanced three-pin XLR connectors accept a standard microphone cable
or other low impedance signal. Optional phone jack, screw terminal, RCA jack or
transformer balanced inputs are also available.

2. Input Gain Controls

These knobs control the input levels for each of the six input channels. When
adjusting the input gain, make certain that the levels are not set too high, or
distortion will result.

The approximate levels for these controls are as follows:

MIC mic level (-50dB ~ -60dB)
MIC ATT instrument level (-30dB ~ -50dB)

AUX line level (-20dB ~ -30dB)

3. EQ Controls

Three-band equalization control provides ±12dB of cut (decrease) or boost
(increase) over the high, mid and low frequency ranges of the individual channel
signals.

HIGH – 10kHz, ±12dB
MID – 1kHz, ±12dB

LOW – 100Hz, ±12dB

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PAM-60/PAM-120 Public Address Amplifier

4. Phantom Power Switch

This switch switches the phantom power supply on or off for all channels. When
the switch is switched on, +24V DC power is supplied to pins 2 and 3 of each
channel’s input connector.

Use phantom power when connecting condenser microphones, which require an
external power supply.

NOTE: It is safe to connect most modern dynamic microphones or line level
devices to the channel inputs when phantom power is activated. However, some
older ribbon microphones may be damaged by phantom power, and certain
unbalanced line level devices may malfunction or produce an audible hum
when phantom power is active.

5. Priority Switch

When selected, these switches will give priority to Channels 1 and/or 2 over all
other channels and audio inputs.

6. Amp In

This input connects an external mixer or preamp with the unit’s power amp.
Inserting a plug into the Amp In jack will disconnect all input signal from the unit’s
internal mixer. Only signal from the external source will be heard.

7. Preamp Output

This output connects the unit with an external power amplifier. Inserting a plug
into the Preamp Out jack will disconnect signal to the unit’s power amp, sending
the output of the internal mixer to the external amplifier.

8. Link Out

This line-level output connects the unit with an external mixdown deck or other
recording source.

9. Link In

This line-level input connects the unit with an external mixer for expanded input
channels.

10. DC Input Terminals

These terminals are provided for the connection of backup battery. Connect a
24VDC battery source to these terminals. Make certain the red terminal is
connected to the battery’s positive (+) side, and the black terminal to the
battery’s negative (-) side.

11. AC and DC Fuse Holders

These holders contain the AC and DC overload protection fuses. If the fuse has
blown out, replace it with a fuse of the same type and rating, as shown below.

If the fuse continues to blow, refer servicing to a qualified service technician.

AC Fuse Ratings

Model 100VAC – 120 VAC 230VAC-240VAC 24VDC

PAM-60 3A / 250V 1.5A / 250V 5A/250V

PAM-120 5A / 250V 2.5A / 250V 10A/250V

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PAM-60/PAM-120 Public Address Amplifier

12. AC Power Input

Connect a standard three-pin AC cable to this connector.

13. Ext Mute

When these two terminals are shorted by wired remote, signals from Input
Channels 3-6 and any optional modules are muted. Signals from Channel 1,
Channel 2, Link In and Chime are not muted.

14. Ext Chime

When these two terminals are shorted, the four-tone chime circuitry is activated.

15. Telephone Input Terminals

These terminals can be connected to a telephone exchange system for paging
purposes.

NOTE: When an active signal is sent through the telephone input, all other input
signals except for AMP IN are muted.

16. Music-On-Hold Terminals (PAM-T AM/FM Tuner Module Only)

These terminals, along with the Telephone Input Terminals (15), are used for
connecting with an external telephone system. When used with the optional
PAM-T module, these terminals supply music-on-hold to the telephone system.

NOTE: When the tuner is switched on, signal from the tuner is constantly sent to
these terminals, and is unaffected by the Master Volume or the PAM-T’s volume
control.

17. Speaker Output Terminal Strip

Connect up to five individual speakers to this strip.
Impedances for 4, 25V, 70V and 100V/250V operation are shown below.
Connect speakers whose combined impedance is equal to or higher than the
rated output impedance, as shown below.

MODEL 4Ω 25V 70V 100V/250V

PAM-60 15.5V 10.5 83 Ω 165 Ω

PAM-120 22V 5.2  42 Ω 83 Ω

18. Impedance Selector

Selects between high impedance operation at 70V or 100V distributed systems.
Note that when speakers are connected to the 4 terminal, this switch is inactive.

19. Antenna Connector (Optional)

This terminal is used to connect the antenna, when used with the optional PAM-T
AM/FM Tuner module.

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PAM-60/PAM-120 Public Address Amplifier

Installation of Speakers

Before connecting speakers, disconnect the AC power cable. Note the proper
connecting terminals as shown below. Make certain that the total impedance is not less
than the rated impedance indicated.

Connecting 4Ω or 8Ω Speaker Systems

When connecting conventional 4 or 8 speaker systems, connect the speaker’s
positive (+) side to the terminal labeled 4. Connect the speaker’s negative (-) side to the
terminal labeled COM. See illustration below:

Connecting High-Voltage Distributed Speaker Systems

When connecting a low-impedance (70W/100W) speaker system in parallel, you can
connect speakers with a total rated input of up to 240W (PAM-240) or 360W (PAM-360).

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PAM-60/PAM-120 Public Address Amplifier

For example, if you are connecting speakers with a rated input of 15W, you can connect
up to 24 speakers in parallel, as shown below:

WARNING: Extreme care must be exercised when connecting low-impedance systems,
as potentially hazardous voltages may be present at these terminals.

Do not install this equipment in a confined space with less-than-adequate ventilation.

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PAM-60/PAM-120 Public Address Amplifier

Applications

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PAM-60/PAM-120 Public Address Amplifier

Specifications

AMPLIFIER SECTION

Rated Output Power (THD 1%) PAM-60: 60W (RMS)

PAM-120: 120W (RMS)

Frequency Response 80Hz–20kHz

T.H.D (at 1kHz Rated Output) Less than 1%

S/N Better than 100dB

Input Sensitivity/Impedance
CH 1~CH 6 1mV~160mV/600
Link In 100mV/15k
Telephone In 0.775V/600
Amp In 1V/47k

Speaker Output/Impedance
PAM-60 60W(4), 83(70V), 165(100V)
PAM-120 120W(4), 42(70V), 83(100V)

Pre Amp Out/Impedance 1V/600

Music On Hold/Impedance 0.775V/600

Link Out/Impedance 500mV/600

Tone Control (100Hz, 10kHz) ±12dB

EQ Control (100Hz, 1kHz, 10kHz) ±12dB

GENERAL

Power Source AC 110V–240V, 50/60Hz, 24VDC

Power Consumption PAM-60: 150W

PAM-120: 300W

Weight PAM-60: 11.4kg (25.1 lbs.)
PAM-120: 13.5kg (29.7 lbs.)

Dimensions 420 (W) x132 (H) x 360 (D) mm

16.5(W) x 5.2 (H) x 14.2 (D) in

* Specifications and design subject to change without notice for improvements.

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PAM-60/PAM-120 Public Address Amplifier

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]

0604PAM60120 PRINTED IN KOREA

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