Inter-m M-106A User manual

Operation Manual
Public Address Amplifier
MA-106A

PUBLIC ADDRESS AMPLIFIER
W lcom
W lcom
A p rsonal w lcom to you from th manag m nt and mploy s of Int r-M
All of the o-workers here at Inter-M are dedi ated to providing ex ellent produ ts with inherently good value,
and we are delighted you have pur hased one of our produ ts.
We sin erely trust this produ t will provide years of satisfa tory servi e, but if anything is not to your omplete
satisfa tion, we will endeavor to make things right.
Wel ome to Inter-M, and thank you for be oming part of our worldwide extended family!
RISK OF ELEC RIC SHOCK
DO NO OPEN
CAutION
CAU ION: O REDUCE HE RISK OF ELEC RIC SHOCK.
DO NO REMOVE COVER (OR BACK).
NO USER-SERVICEABLE PAR S INSIDE.
REFER SERVICING O QUALIFIED SERVICE PERSONNEL.
WARNING
o prevent fire or shock hazard, do not
expose the unit to rain or moisture.
*WARNING FOR YOUR PRO EC ION PLEASE READ HE FOLLOWING-WA ER AND MOIS URE: 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): he 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.
* his apparatus shall not be exposed to dripping or splashing and no objects filled with liquids, such vases, shall be placed on the apparatus.
* his apparatus shall be connected to a mains socket outlet with a protective earthing connection.
*
It has heed to be easy to disconnect the device. o disconnect the device from power, separate AC input cable from inlet or unplug the AC Cord.
* he socket-outlet shall be installed near the equipment and shall be easily accessible.
CAutION
* hese servicing instructions are for use by qualified service personnel only. o 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
*his 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. hese limits are
designed to provide reasonable protection against harmful interference when the equipment is operated in a commercial environment. his 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.
his 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.
his symbol is intended to alert the user to the
presence of important operation and maintenance
(servicing) instructions in the literature accompanying
the appliance.
Caution: o 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.

PUBLIC ADDRESS AMPLIFIER
1
MA-106A
Cont nts
Cont nts
Unpacking .......................................................................................................................................2
Installation
Environment....................................................................................................................................2
Important Safety Instru tions.............................................................................................................2
F atur s............................................................................................................................................3
Op ration ........................................................................................................................................3
Front Pan l ......................................................................................................................................4
R ar Pan l .......................................................................................................................................5
Conn cting Sp ak rs.....................................................................................................................8
Typical Applications .......................................................................................................................9
Block Diagram ..............................................................................................................................10
Sp cifications ................................................................................................................................11
S rvic
Pro edures....................................................................................................................................13
S hemati .....................................................................................................................................13
Parts List .......................................................................................................................................13
Variations and Options ...............................................................................................................13
Warranty .......................................................................................................................................13

PUBLIC ADDRESS AMPLIFIER
2MA-106A
Installation
Unpacking
Unpacking
Although your MA-106A is neither ompli ated nor diffi ult to operate, we re ommend you take a few minutes
to read this brief manual and familiarize yourself with the important information regarding produ t features,
setup and operation.
As with most ele troni devi es, we strongly re ommend you retain the original pa kaging. In the unlikely event
the produ t must be returned for servi ing, the original pa kaging (or reasonable equivalent) is required.
Installation
Environm nt
Never pla e this produ t in an environment whi h ould alter its performan e or redu e its servi e life. Su h
environments usually in lude high levels of heat, dust, moisture, and vibration.
IMPORTANT SAFETY INSTRUCTIONS
1. Read these instru tions.
2. Keep these instru tions.
3. Heed all warnings.
4. Follow all instru tions.
5. Do not use this apparatus near water.
6. Clean only with dry loth.
7. Do not blo k any ventilation openings. Install in a ordan e with the manufa turer’s instru tions.
8. Do not install near any heat sour es su h as radiators, heat registers, stoves, or other apparatus (in luding
amplifiers) that produ e 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, onsult
an ele tri ian for repla ement of the obsolete outlet.
10. Prote t the power ord from being walked on or pin hed parti ularly at plugs, onvenien e re epta les, and
the point where they exit from the apparatus.
11. Only use atta hments/a essories spe ified by the manufa turer.
12. Use only with the art, stand, tripod, bra ket, or table spe ified by the manufa turer, or sold with the apparatus.
When a art is used, use aution when moving the art/apparatus ombination to avoid injury from tip-over.
13. Unplug this apparatus during lightning storms or when unused for long periods of time.
14. Refer all servi ing to qualified servi e personnel. Servi ing is required when the
apparatus has been damaged in any way, su h as power-supply ord or plug is
damaged, liquid has been spilled or obje ts have fallen into the apparatus, the
apparatus has been exposed to rain or moisture, does not operate normally, or has
been dropped.
S3125A
S3125A

PUBLIC ADDRESS AMPLIFIER
3
MA-106A
F atur s
F atur s
F atur s
- 1U Size Compa t Design
- 60W High Effi ien y Digital Amp Cir uit
- SMPS Power Cir uit
- Volume ontrol on INPUT 1~3 – enable to adjust ea h input hannel level
- Display the input signal of INPUT 1~3
- Base and Treble Controls
- Diverse Features -Phantom Mi Power, External MUTE, et .
- PRIORITY Fun tion
- MIX Configuration DIP swit hes
- Without input signal for 25 Min, automati ally onverted to Master System standby Mode
Op ration
Op ration
1. Before you plug the power ord to AC outlet, please set the power swit h OFF, Tone Control enter, and
volume level minimum.
2. Please make sure the speakers and input ja ks are properly onne ted before turn the power swit h on.
3. Be sure the AC power is orre t voltage before you plug into the power ord.
4. Please push the power swit h, then the power input LED is on and the unit will be operated.
5. Please use your own with adjustment the volume using ea h input volume and master volume, the tone using
the tone ontrol.

PUBLIC ADDRESS AMPLIFIER
4MA-106A
Front Pan l
Front Pan l
1. INPUT 2 JACK
This is a 3.5mm Tip Ring Sleeve (TRS) ja k on the front panel that drives input 2. This ja k is very useful for
onne ting MP3 players, and overrides all input 2 onne tions on the ba k panel.
2. INPUT SIGNAL LEDS
These LEDs flash when input signal is present.
3. INPUT LEVEL CONTROLS
These ontrol the level of the three input hannels.
4. BASS AND TREBLE CONTROLS
These ontrol the bass and treble of the main amplifier output.
5. MASTER VOLUME CONTROL
This ontrols the main amplifier output level. There is a separate rear panel level ontrol for zone 2 output.
6. POWER LED
This LED lights blue when the unit is powered on and a tive, and red when in standby mode.
7. POWER SWITCH
This swit h turns the power on or off.
12
357
461 2 64
3 5 7

PUBLIC ADDRESS AMPLIFIER
5
MA-106A
R ar Pan l
R ar Pan l
1. AC MAINS
Conne t this able to an AC outlet.
2. MAIN SPEAKER OUTPUTS
This 5.08mm Euroblo k onne tor is used for the main speaker output wiring. For low impedan e speaker
loads, minimum 4Ω, onne t between the COM and 16V/4Ω pins. For 70V/82Ω or 100V/167Ω speaker
loads (USA/CANADA & Asso iated : 25V/11Ω or 70V/82Ω), the LINK wire must first be installed between
the 16V/4Ω pin and OPT IN pin, then onne t the speaker load between COM and 70V or 100V pins.
3. ZONE 2 AND PREAMP OUTPUTS
In addition to the main 60 Watt amplifier output, there is a separate ZONE 2 output whi h is a swit h
sele table mix of hannels 1, 2, or 3. This output is not effe ted by the priority du king/mute a tion or by
the bass/treble EQ ontrols.
The ZONE-2 output provides two signals; 1) a low impedan e output that is apable of ontinuously driving
1 Watt into an 8 Ohm loudspeaker, and 2) a 600 Ohms transformer balan ed output. Zone 2 output is
ontrolled by the rear panel Zone 2 level ontrol, as well as the three hannel assign DIP swit hes.
The PRE OUT onne tion is used for driving additional external devi es with the same signal that drives the
main MA-106A power amplifier. The PRE OUT 600 Ohms output signal is taken before the master volume
ontrol.
4. INPUT 3 CONNECTORS
3.5mm Euroblo k onne tors and summed stereo RCA ja ks are used for input 3. If wiring an unbalan ed
input signal into a balan ed Euroblo k input, be sure to ground the (-) input pin.
5. INPUT 2 CONNECTORS
3.5mm Euroblo k onne tors and summed stereo RCA ja ks are used for input 2. If wiring an unbalan ed
input signal into a balan ed Euroblo k input, be sure to ground the (-) input pin.
123456
121110978

PUBLIC ADDRESS AMPLIFIER
6MA-106A
6a) MANUAL MUTE CONTACT CLOSURE
Conta t Closure between pins 1 and G will mute input hannel 2, or mute hannels 2 and 3 together if they
are linked using mix onfiguration swit h #6. This is typi ally used when a mi rophone plugged into hannel
1 has a push-to-talk swit h, whereby the pressing of the swit h not only turns on the mi but also mutes the
signal on hannel 2, or hannels 2 and 3 if they are linked. When the swit h is released, the signal on
hannels 2 and 3 returns.
6b) MASTER SYSTEM STANDBY
The MA-106A has a power saving standby mode whi h an be triggered by 25 minutes of audio
ina tivity(below a ertain audio input level), or by onta t losure of the Master System Standby onne tor
pins G & 2. When in standby mode, the front panel power LED will turn red, hanging ba k to blue for
normal operating mode. Standby mode is ended when there is audio signal present again, or when the
Master System Standby ir uit is opened. Master system standby has priority over standby due to ina tivity.
7. ZONE 2 LEVEL CONTROL
This ontrols the level of the Zone 2 output signal.
8. MIX CONFIGURATION DIP SWITCHES
- Swit hes 1, 2, and 3: Zone 2 Assign
These assign ea h input to Zone 2 output, post-level ontrol. There is no effe t to the main output mix.
- Swit hes 4-5: VOX Trigger -
The MA-106A has the ability to trigger a mute on hannel 2 or 3 from the presen e of an audio signal on
hannel 1 or 2. This is alled Voi e Operated Swit hing, or VOX. Input 2 has priority over input 3, and
input 1 has priority over input 2. Input 1 also has the ability to use a onta t losure trigger su h as a mi
push-to-talk swit h for priority muting of hannel 2. Additionally, input 1 an be set to have priority over
both inputs 2 and 3 together (see swit h 6).
The MA-106A has audio dete ting LEDs on ea h input. When the VOX TRIG swit hes are set to ON for
inputs 1 or 2, the same signal level whi h a tivates the LED is used as the VOX trigger. VOX mutes the
dependent hannel until the trigger signal falls ba k below the LED threshold. Ea h input features a rear
panel gain trim that first optimizes the overall input sensitivity for ea h input, but an also serve to fine-tune
the sensitivity of the signal dete tor whi h reates the VOX trigger point for ea h input.
- Swit h 6: Mute Link 2&3
When this swit h is turned on, it sets the hannel 1 VOX trigger or Manual Mute onta t losure to mute
both hannels 2 and 3. If only hannel 2 is to be affe ted, leave it off.
- Swit h 7: Low-Cut Filter
This swit h turns on a 400Hz 6dB/o t low- ut filter affe ting the main and PRE outputs but not the zone 2
outputs. This is useful for providing the proper EQ for paging horns.
- Swit h 8: CH 1 MIC Phantom Power
This provides +18V phantom power to input 1 for use with ondenser and ele tret mi rophones.
9. INPUT 3 GAIN CONTROL
Input 3 gain trim range is adjustable from -10dB to +10dB.
10. INPUT 2 GAIN CONTROL
Input 2 gain trim range is adjustable from -10dB to +10dB. This ontrol is also used to fine tune the signal
threshold that will trigger the muting of input 3.

PUBLIC ADDRESS AMPLIFIER
7
MA-106A
11. INPUT 1 GAIN CONTROL
Input 1 gain trim range is adjustable from 0dB to +50dB. A typi al line level input setting would be lose to
0dB. A typi al Mi rophone input setting would be loser to +50dB. This ontrol is also used to fine tune the
signal threshold that will trigger the muting of input 2 or inputs 2 and 3 if linked.
12. INPUT 1 CONNECTOR
A 3.5mm Euroblo k onne tor is used for input 1, and an be used as a mi level or line level input. As a
balan ed line input, it an onne t to a telephone paging system instead of a mi rophone. If the input signal
is unbalan ed, be sure to ground the unused (-) input pin.

PUBLIC ADDRESS AMPLIFIER
8MA-106A
Conn cting Sp ak rs
Conn cting Sp ak rs
Before onne ting speakers to MA-106A unit, be sure to dis onne t the AC power able.
NOTE : 1. Make ertain that the total impedan e is not less than the rated impedan e indi ated.
2. Don’t have to use several speaker terminals at the same time.
3. If you’re just dealing with the high impedan e terminal, then make sure that 4Ω output terminal is
onne ted with OPT-IN terminal.
4Ω
SPEAKER 8Ω8Ω
- FOR 70V TERMINAL - FOR 100V TERMINAL
(ONE 4Ω SPEAKER) (TWO 8Ω SPEAKERS)
- FOR 4Ω TERMINAL
*3*3

PUBLIC ADDRESS AMPLIFIER
9
MA-106A
Typical Applications
Typical Applications
- RESTAURANT SYSTEM
This two tiered priority du king example allows for ba kground musi to be present on hannel 3, whi h an be
overridden by the presen e of audio on hannel 2 from a TV signal, both of whi h an be overridden by a
keyed mi rophone announ ement on hannel 1. Stereo audio signals using RCA ja ks are summed to mono at
the input.
In this example, all three inputs are assigned to Zone 2 via the DIP swit hes. Be ause the mi is set up for push-
to-talk, the IN 1 VOX trigger swit h is left off. IN 2 VOX trigger is swit hed on however, so that signal from the
TV will automati ally override the ba kground musi . Mute Link is swit hed on so that the keyed mi will mute
both Inputs 1 and 2.
A 70V distributed speaker system runs off of the main power amplifier, and an external amplifier is run off of
the Zone 2 600Ω output. A small 1W 8Ω speaker is run off of the Zone 2 Low Z output.

PUBLIC ADDRESS AMPLIFIER
10 MA-106A
Block Diagram
Block Diagram

PUBLIC ADDRESS AMPLIFIER
11
MA-106A
Sp cifications
Sp cifications
MA-106A
Rated Output Power (T.H.D 1%) 60W(RMS)
Output Voltage EC & Asso iated, JAPAN 4Ω/16V 82Ω/70V 167Ω/100V
USA/CANADA & Asso iated 4Ω/16V 11Ω/25V 82Ω/70V
Frequen y Response Input 1, 2, 3 +1/-3dB, 80Hz-15kHz
(1W@1kHz)
T.H.D (60W@1kHz) Less than 1%
S/N Ratio
(60W@1kHz A-weighted)
INPUT 1, 2, 3 Better than 70dB
Input Sensitivity INPUT 1 -10dBV to -50dBV
INPUT 2, 3 0dBV to -20dBV
Tone Control BASS (100Hz) ±10dB
TREBLE (10kHz) ±10dB
Residual Noise Master volume min -65dB
(Input 1-3 vol min, tone at enter) Master volume max -55dB
Zone 2 Output
Rated power 8Ω (RMS, THD 3%) 1W
BAL 600Ω2.4V
PRE Out (input -10dBV) 0dBV
SW1 Zone 2 Assign Input 1
SW2 Zone 2 Assign Input 2
SW3 Zone 2 Assign input 3
SW4 VOX Trigger Input 1
SW5 VOX Trigger Input 2
SW6 Mute Link Input 2 & 3
SW7 Low-Cut, 400Hz 6dB/O t.
SW8 INPUT1 Phantom Power, +18V
Manual Mute Conta t Closure Pin 1 & G=Input 1 Mute Trigger
Master System Standby Conta t Closure Pins G & 2=Power Standby
Operating Temperature -10°C ~ +40°C
Power Sour e 100–120VAC or 220–240VAC, 50/60Hz
(Supplied AC mains transformer depends on ountry requirements)
Power Consumption 24W
Weight (SET) 3.1kg/6.8lb
Dimensions (SET) 300(W) x 44(H) x 230(D)mm/11.8(H) x 1.7(H) x 9.1(D)in
* Spe ifi ations and design subje t to hange without noti e.
* R mark : 1. All spe ifi ations are measured with AES-17 filter.
2. This system is used digital Amplifier (PWM Modulation) so the PWM leakage signal will appear to
output terminal, but it doesn’t matter. You an’t hear the PWM leakage sound be ause of PWM
frequen ies is very higher than Audio frequen ies.
* 0dBV = 1.0Vrms
Mix Configuration Swit hes

PUBLIC ADDRESS AMPLIFIER
12 MA-106A
※DIMENSIONS

PUBLIC ADDRESS AMPLIFIER
13
MA-106A 13
MA-106A
S rvic
S rvic
Proc dur s
Take steps to insure the problem is not related to operator error or other produ ts within the system. Information
provided in the troubleshooting portion of this manual may help with this pro ess. On e it is ertain that the
problem is related to the produ t onta t your warranty provider as des ribed in the warranty se tion of this
manual.
Sch matic
A S hemati is available by onta ting your warranty provider.
Parts List
A Parts List is available by onta ting your warranty provider.
Warranty
Warranty
Warranty terms and onditions vary by ountry and may not be the same for all produ ts. Terms and onditions
of warranty for a given produ t may be determined first by lo ating the appropriate ountry whi h the produ t
was pur hased in, then by lo ating the produ t type.
To obtain spe ifi warranty information and available servi e lo ations onta t Inter-M dire tly or the
authorized Inter-M Distributor for your spe ifi ountry or region.
Variations and Options
Variations and Options
Variations
Variations of this produ t exist to refle t the variations in AC power requirements throughout the world. Produ t
supplied through lo al sour es are ompatible with lo al AC power requirements.
Options
No optional items are available for this produ t.

MADE IN KOREA
September 2021 155208
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 : [email protected]
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 : [email protected]