Nilfisk MAC 2.3, MAC 2.4 User Manual

MAC

2.2/2.3/2.4

User's Manual

STEREO POWER AMPLIFIER

R

LTO

www.altoproaudio.com

Version 1.2 APRIL 2005

English

SAFETY RELATED SYMBOLS

CAUTION

RISK OFELECTRIC SHOCK

DO NOTOPEN

This symbol, wherever used, alerts you to the pre­sence of un-insulated and dangerous voltages with­in the product enclosure. These are voltages that
may be sufficient to constitute the risk of electric
shock or death.

This symbol, wherever used, alerts you to impo­rtant operating and maintenance instructions.
Please read.

Protective Ground Terminal

AC mains (Alternating Current)

Hazardous Live Terminal

ON: Denotes the product is turned on.

OFF: Denotes the product is turned off.

WARNING

Describes precautions that should be observed to
prevent the possibility of death or injury to the user.

the recommended fuse type as indicated in this
manual. Do not short-circuit the fuse holder. Before
replacing the fuse, make sure that the product is
OFF and disconnected from the AC outlet.

Protective Ground

Before turning the product ON, make sure that it is
connected to Ground. This is to prevent the risk of
electric shock.

Never cut internal or external Ground wires. Likewise,
never remove Ground wiring from the Protective
Ground Terminal.

Operating Conditions

Always install in accordance with the manufacturer's
instructions.

To avoid the risk of electric shock and damage, do
not subject this product to any liquid/rain or moisture.
Do not use this product when in close proximity to
water.

Do not install this product near any direct heat source.

Do not block areas of ventilation. Failure to do so
could result in fire.

Keep product away from naked flames.

CAUTION

Describes precautions that should be observed to
prevent damage to the product.

WARNING

Power Supply

Ensure that the mains source voltage (AC outlet)
matches the voltage rating of the product. Failure
to do so could result in damage to the product and
possibly the user.

Unplug the product before electrical storms occur
and when unused for long periods of time to reduce
the risk of electric shock or fire.

External Connection

Always use proper ready-made insulated mains
cabling (power cord). Failure to do so could result
in shock/death or fire. If in doubt, seek advice from
a registered electrician.

Do Not Remove Any Covers

Within the product are areas where high voltages
may present. To reduce the risk of electric shock do
not remove any covers unless the AC mains power
cord is removed.

Covers should be removed by qualified service
personnel only.

No user serviceable parts inside.

Fuse

To prevent fire and damage to the product, use only

IMPORTANT SAFETY INSTRUCTIONS

Read these instructions

Follow all instructions

Keep these instructions. Do not discard.

Heed all warnings.

Only use attachments/accessories specified by the
manufacturer.

Power Cord and Plug

Do not tamper with the power cord or plug. These are
designed for your safety.

Do not remove Ground connections!

If the plug does not fit your AC outlet seek advice from
a qualified electrician.

Protect the power cord and plug from any physical
stress to avoid risk of electric shock.

Do not place heavy objects on the power cord. This
could cause electric shock or fire.

Cleaning

When required, either blow off dust from the product
or use a dry cloth.

Do not use any solvents such as Benzol or Alcohol.
For safety, keep product clean and free from dust.

Servicing

Refer all servicing to qualified service personnel only.

Do not perform any servicing other than those instruc­tions contained within the User's Manual.

1

PREFACE

Dear Customer:

Thanks for choosing LTO MAC 2.2/2.3/2.4 Stereo Power Amplifier which is the result of our LTO AUDIO TEAM's
endeavors.

For LTO AUDIO TEAM music and audio are much more than a job, they are a passion and an obsession!

We have been designing professional audio products for a long time in cooperation with many of the world's major
brands.

The LTO line represents unparalleled analogue and digital products made by musicians, for musicians. With our
design centres in Italy, Netherlands, and United Kingdom we provide you with world-class designs, while our software
development teams continue to develop an impressive range of audio specific algorithms.

By purchasing our products you become the most important member of our AUDIO TEAM. We would likeLTO LTO

to share with you our passion for what we design and we invite you to make suggestions, which will aid us in developing

future products for you. We guarantee you our commitment to quality, continual research and development, and of course
the best performance/price ratio.

Our LTO MAC 2.2/2.3/2.4 Stereo Power Amplifier is the result of many hours of listening and tests involving

common people, area experts, musicians and technicians. The result of this effort is the sophisticated circuit design
featuring high power and superb quality together with superior reliability and stability to provide the highest possible
audio performance.

We would like to thank all the people that worked with us to make a vision real! Our designers and LTO staff
made the MAC 2.2/2.3/2.4 Stereo Power Amplifier, a very reliable and high quality product ready for all your
venues. And thanks to their passion for music and professional audio it has been possible for us to offer you, our

most important team member, our continued support too.

Thank you very much.

LTO AUDIO TEAM

2

TABLE OF CONTENTS

1. INTRODUCTION.....................................................................................................................................4

2. FEATURE LIST.......................................................................................................................................4

3. CONTROL ELEMENTS..........................................................................................................................4

3.1 The Front Panel

3.2 The Rear Panel

4. INSTALLATION & CONNECTION..........................................................................................................6

4.1 Mains Connection

4.2 Rack Mounting

4.3 Audio Connection

a. Wiring Configuration

b. In Line Connection

5. OPERATION ..........................................................................................................................................7

5.1 Operate MAC 2.2/2.3/2.4 in Stereo Mode

5.1 Operate MAC 2.2/2.3/2.4 in Parallel (Mono) Mode

5.1 Operate MAC 2.2/2.3/2.4 in Bridged Mode

6. CAUTION FOR APPLICATION .............................................................................................................9

6.1 General Application Instruction

6.2 Caution for Speaker Connection

7. TECHNICAL SPECIFICATIONS............................................................................................................10

7.1 Specifications

7.2 Block Diagram

8. WARRANTY..........................................................................................................................................12

3

1. INTRODUCTION

Thank you very much for expressing your confidence in products by purchasing our MAC 2.2/2.3/2.4 StereoLTO
Power Amplifier. With the MAC 2.2/2.3/2.4 you have acquired an extremely musical and flexible high power
amplifier which is based on many years of experience and finding in amplifier technology and is used through the
world in the renowned studios. The MAC 2.2/2.3/2.4 is used for professional output of stage stereo with excellent
performance. Output power can be adjusted at the user's demand, and the sound quality and protecting circuit are
both sophisticated.
The front panel presents you with 6 LEDs (power LED, protection LED, clip & signal LED for each channel) and 2
level controls, you can operate this unit more precise and easier. The output connectors are speak-on jacks and
binding post terminals, which are used for better matching. Before connecting this unit into your sound system,
please make sure it is powered down to prevent any electric shock.

2. FEATURE LIST

Sophisticated protecting circuit protects the machine from improper tampering
Excellent frequency echo and sound quality
High fidelity and low noise
Balanced XLR and 1/4" TRS input connectors
Output connectors are speak-on jacks and binding post terminals
Stereo mode, parallel mode and bridged mode are available
High-speed and low noise fan for releasing heat. The inside temperature determines the fan speed.

100mV, the SIG LED lights up. When there is overload, the CLIP LED lights up. If anything abnormal happens to
the circuits, the CLIP LED will be continuously on, with no action from the circuits. This helps the user todetermine

which status it is in.
Solid and durable, can be mounted into a cabinet
Manufactured under QS9000, VDA6.1 certified management system

thanIndicator for the output balance, as well as status indicators of SIG and CLIP. When there is any signal is more

3. CONTROL ELEMENTS

3.1 Front Panel

ON

OFF

POWER

1

1 . Mains Switch

This switch turns on and off the unit by controlling both phases.

2 . Power LED

This Power LED lights up when the unit is powered up.

3. Protection LED

This red LED lights up when the thermal-protection system is working, no signal is output during this
protection period. When any overheating occurs inside the unit (the critical temperature is 80 C), you should
speed up the air circulation or decrease the signal level for avoiding overheating. If the problem is corrected
the protection systems deactivate automatically, this LED goes out, and the normal amplifier operation is
resumed.

1

2

3

3

2

CH1 CH2

POWER

PROT

CLIP

CLIP

SIG

SIG

5

4

0

4. Clip Signal LED

4
The clip LEDs light up when distortion reaches or exceeds 0.5% approximately, which means the unit is being driven
by excessively high signal source, and you'd better adjust the level control until these LEDs go out.

4

Signal LED
These signal indicators light up when the output is more than 100mV.

5. Level Control

5

These level controls are used to adjust the output signal level, you'd better adjust them properly to avoid any distortion.

3.2 Rear Panel

11

2

3

2

3

CH-2

1

1

CH-1

BRIDGED INPUT

LINE

BALANCED
INPUT

LINE

(+)

12

3

(GND)

-

()

OFF ON

LF 30HZ

FILTER

1.15V/20K

STEREO

PARALLEL

(MONO)

OFF ON

CLIPLIMT

INPUT

CONNECTION

BRIDGED

SRT

T(+)

-

R( )

S(GND)

A104

CH-1 CH-2

BRIDGED

MONO

CHANNEL1 CHANNEL2

12 9810 13

6. Breaker

6

This switch works as fuse for protecting the unit from damage. When the unit is overloaded or the temperature
inside the unit is too high, this pushing-button will spring up and break the power supply. The power supply
will be restored with pushing the switch down again.

7. AC Inlet

7

This connector is meant for the connection of the supplied main cord. Do not insert the power cord into this
unit until voltage has been correctly set. Do not plug the power cord into the mains until the voltage has been

correctly set.

6

BREAKER

WARNING

TOREDUCE THE RISKOF FIRE
ORELECTRIC SHOCK, DONOT
EXPOSETHIS APPARATUSTO
RAINOR MOISTURE.
SEEINSTRUCTION BEFORE
USING!

Apparaten skall anslutas till
jordat uttag nar den ansluts
till ett natverk

MODEL

SERIAL

7

8. Input Connectors

8

These connectors include the balanced XLR servo connectors and 1/4" TRS phone jacks. It is used to connect
the input signal.

9. Output Connectors

9

These connectors include the speak-on jacks and binding post terminals, you can output the powered signal
by the specific output connectors according to the actual application circumstance.

Caution: turn off the unit before connecting the output connectors so as to avoid any electric shock!

10. Clip Limit Switch

10

Set this switch at "ON" position, once the output level is above the maximum level, the clip limt begin, which
is used to keep fixed output level for protecting apparatus. If the switch is at "OFF", this clip limt function
doesn't work.

11. LF 30Hz Filter

11

Setting this switch to "ON" is equal to adding an appropriate low-pass filter in the input circuit, which is used to protect
the speaker system from the damage caused by large subsonic frequencies.

12. Mode Selector

12

The MAC 2.2/2.3/2.4 stereo power amplifier presents three operating modes:

- Stereo Mode

In this mode, CHA and CHB operate independently (as a conventional stereo amplifier)
The CHA input signal will be output from the CHA output connector, and CHB input signal will be output from
the CHB output connector.

- Parallel Mono Mode

In this mode, CHA input signal will be output from the output connectors of both channels, detail wiring
diagram you can refer to chapter 5.

- Bridged Mode

5

In this mode, CHA input signal will be output from the bridge output connector, detail wiring diagram you can
refer to chapter 5.

13. Fan

13

This fan release the heating from the unit by accelerating the air circulation (air flowing from front to back), and
the speed is continuously variable.

4. INSTALLATION & CONNECTION

4.1 Mains Connection

Do not insert the power cord into this unit until voltage has been correctly set. Do not plug the power cord into the

mains until the voltage has been correctly set.

Amplifier is supplied with the correct If you can't power up this unit while turning
on the Mains Switch (1), please check the Breaker (6) on the rear panel first, maybe it is pressed to reset. Otherwise,
contact the technician or qualified personnel for

Caution: To reduce the risk of electric shock, do not perform any servicing other than contained in this manual unless

you are qualified to do so.

your unit into the sound system. This is important to prevent damage to the unit itself as well as other consequent
speaker The mains connection of the MAC 2.2/2.3/2.4 Professional Stereo Amplifier is made by usingsystem.
the enclosed power cord and a standard IEC receptacle, and it meets all of the international safety certification

requirements.

4.2 Rack Mounting

The most secure mounting is on a universal rack shelf available from various rack manufactures or your music
dealer. The MAC 2.2/2.3/2.4 Professional Stereo Amplifier fits into one standard 19" rack unit of space.Be sure
that there is enough air space around the unit for sufficient ventilation. If heat release is inadequate, this unit
will retain heat inside, which may cause the protection, or even a fire.

Please turn off this unit before any installation and connection, esp. when you connect

Please ensure that the MAC 2.2/2.3/2.4 Professional Stereo

voltage before turning on this unit.

any service.

4.3 Audio onnectionC

The presents with balanced XLR connectors and 1/4" TRS

LTO MAC Professional High Power Amplifier

phone jack and it can be interfaced by several ways to support a variety of applications without any signal loss.

a. Wiring Configuration

Either the 1/4" TRS (Tip-Ring-Sleeve) phone jack or the XLR servo connector can be wired in balanced and unbal­anced modes, which will be determined by the actual application status, Please wire your systems as the following
examples:

For 1/4" Phone jack

For XLR connector

2.2/2.3/2.4

+

Tip

Sleeve

TS Type Unbalanced

Pin1 ( )

Ring

TRS Type Balanced TRS Type Unbalanced

Pin2 (+)

Pin3 (-)
(Linked to Pin1 manually, )

+

-

Tip

Sleeve

Pin3 (-)

Pin1 ( )

Ring

+

Tip

Sleeve

Pin2 (+)

XLR Type Unbalanced XLR Type alancedB

b. In Line Connection

For these applications, the provides XLR con

2.2/2.3/2.4

6

nectors and 1/4" TRS phone jack toMAC stereo power amplifier

easily interface with most professional audio devices. Follow the configuration examples below for your particular
connection.

Balanced

TIPRING SLEEVE

3

21

TIPRING SLEEVE

SLEEVERING TIP

Tip

Ring

1

3

2

1

3

2

Sleeve

Ring

Sleeve

1
2

3

Tip

Tip
Ring

Sleeve

1
2

3

1
2
3

Unbalanced

TIPRING SLEEVE

TIPSLEEVE

1

3

2

TIPSLEEVE

TIPRING SLEEVE

TIPSLEEVE

TIPRING SLEEVE

1

3

2

SLEEVETIP

SLEEVERING TIP

1

3

2

1

3

2

1

3

2

Ring

Sleeve

Sleeve

Sleeve

Ring

Sleeve

Sleeve

Ring

Sleeve

Tip

Tip

1
2
3

Tip

Tip

Tip

Tip

1
2

3

1
2
3

1
2
3

Cent er

Screen

Tip

Sleeve

Tip
Ring

Sleeve

Cent er

Screen

Centre

Screen

1
2
3

5.OPERATION

The MAC provides three operating modes with each unit: s2.2/2.3/2.4 tereo mode, parallelstereo power amplifie
(mono) mode and bridged mode, you can decide each specific operating

Following exampleswill show you the typical connections, you can refer to install your MACcircumstance. 2.2/2.3/2.4

into a sound system:

5.1 Operate MAC in Stereo Mode2.2/2.3/2.4

In this mode, channel A and channel B operate independently ( as a conventional stereo amplifier). The channel

A input signal will be output from the channel A output connectors, and the channel B input signal will be output

from the channel B output connectors.

Input wiring tips

BALANCED UNBALANCED

CHANNEL B

CHANNEL A

GND

1

3

2

INPUT

FROM

SOURCE

+ +

SHIELD SHIELD

CH-2

LINE

2

1

3

OFF ON

BALANCED
INPUT

LINE

2

1

3

OFF ON

CH-1

BRIDGEDINPUT

BRIDGED

STEREO

PARALLEL

(MONO)

(+)

LF30HZ

FILTER

1.15V/20K

PARALLEL

(MONO)

CLIPLIMT

12

3

-

()

CONNECTION

(GND)

BRIDGED

STEREO

SHIELD

1

3

2

INPUT

INPUT

FROM

SOURCE

SRT

T(+)

-

R( )

S(GND)

CH-1 CH-2

CHANNEL1 CHANNEL2

A104

mode according to your actual application

WARNING

TOREDUCE THERISK OF FIRE

BREAKER

ORELECTRIC SHOCK,DO NOT
EXPOSETHIS APPARATUSTO
RAINOR MOISTURE.
SEEINSTRUCTION BEFORE

BRIDGED

MONO

USING!

Apparatenskall anslutas till
jordatuttag nar den ansluts
tillett natverk

Channel B

MODEL

SERIAL

+

Channel A

+

7

CHANNEL B

CHANNEL A

Input wiring tips

BALANCED UNBALANCED

(+)

LF30HZ

FILTER

1.15V/20K

PARALLEL

(MONO)

CLIPLIMT

3

-

()

CONNECTION

12

(GND)

BRIDGED

STEREO

SHIELD

1

3

2

INPUT

INPUT

SRT

T(+)

-

R( )

S(GND)

GND

1

3

2

INPUT

FROM

SOURCE

+ +

SHIELD SHIELD

CH-2

LINE

2

1

3

OFF ON

BALANCED
INPUT

LINE

2

1

3

OFF ON

CH-1

BRIDGEDINPUT

BRIDGED

STEREO

PARALLEL

(MONO)

FROM

SOURCE

A104

CH-1 CH-2

BRIDGED

MONO

CHANNEL1 CHANNEL 2

TOREDUCE THERISK OF FIRE

BREAKER

ORELECTRIC SHOCK,DO NOT
EXPOSETHIS APPARATUSTO
RAINOR MOISTURE.
SEEINSTRUCTION BEFORE
USING!

Apparatenskall anslutas till
jordatuttag nar den ansluts
tillett natverk

Channel B

PIN 1+

PIN 1-

WARNING

MODEL

SERIAL

+

Channel A

PIN 1+

+

PIN 1-

5.2 Operate MAC in Parallel (Mono) Mode2.2/2.3/2.4

In this mode, the channel A input signal will be output from the output connectors of both channels. The channel
B input jack is not used, the channel A and B volumes can be adjusted independently.

Input wiring tips

BALANCED UNBALANCED

NO USING

CHANNEL A

GND

1

3

2

INPUT

FROM

SOURCE

+ +

SHIELD SHIELD

CH-2

LINE

2

1

3

OFF ON

BALANCED
INPUT

LINE

2

1

3

OFF ON

CH-1

BRIDGEDINPUT

BRIDGED

STEREO

PARALLEL

(MONO)

(+)

LF30HZ

FILTER

1.15V/20K

PARALLEL

(MONO)

CLIPLIMT

-

()

3

12

(GND)

STEREO

INPUT

CONNECTION

BRIDGED

INPUT

SHIELD

1

3

2

FROM

SOURCE

SRT

T(+)

-

R( )

S(GND)

A104

CH-1 CH-2

BRIDGED

MONO

CHANNEL1 CHANNEL 2

TOREDUCE THERISK OF FIRE

BREAKER

ORELECTRIC SHOCK,DO NOT
EXPOSETHIS APPARATUSTO
RAINOR MOISTURE.
SEEINSTRUCTION BEFORE
USING!

Apparatenskall anslutas till
jordatuttag nar den ansluts
tillett natverk

Channel B

WARNING

MODEL

SERIAL

+

Channel A

+

8

NO USING

CHANNEL A

Input wiring tips

BALANCED UNBALANCED

(+)

()

OFF ON

LF30HZ

FILTER

1.15V/20K

PARALLEL

(MONO)

OFF ON

CLIPLIMT

3

-

12

(GND)

STEREO

INPUT

CONNECTION

BRIDGED

SHIELD

1

3

2

INPUT

SRT

T(+)

-

R()

S(GND)

GND

1

3

2

INPUT

FROM

SOURCE

+ +

SHIELD SHIELD

CH-2

LINE

2

1

3

BALANCED
INPUT

LINE

2

1

3

CH-1

BRIDGEDINPUT

BRIDGED

STEREO

PARALLEL

(MONO)

FROM

SOURCE

A104

CH-1 CH-2

BRIDGED

MONO

CHANNEL1 CHANNEL2

TOREDUCE THERISK OF FIRE

BREAKER

ORELECTRIC SHOCK,DO NOT
EXPOSETHISAPPARATUS TO
RAINOR MOISTURE.
SEEINSTRUCTION BEFORE
USING!

Apparatenskall anslutas till
jordatuttag nar den ansluts
tillett natverk

Channel B

PIN 1+

PIN 1-

WARNING

MODEL

SERIAL

+

Channel A

PIN 1+

+

PIN 1-

5.3 Operate MAC in Bridged Mode2.2/2.3/2.4

In this mode, the channel A input signal will be output from the bridge output connectors. In this case, use the
channel A volume control to adjust the volume, keep the volume control of channel B turned completely down
(counterclockwise). Bridged mode is intended for driving loads with a total impedance of 4 ohms or greater.

Input wiring tips

BALANCED UNBALANCED

(+)

LF30HZ

FILTER

1.15V/20K

PARALLEL

(MONO)

CLIPLIMT

3

-

()

CONNECTION

12

(GND)

BRIDGED

STEREO

SHIELD

1

3

2

INPUT

INPUT

FROM

SOURCE

SRT

T(+)

-

R( )

S(GND)

A104

CH-1 CH-2

BRIDGED

MONO

CHANNEL1 CHANNEL2

BREAKER

WARNING

TOREDUCE THERISK OF FIRE
ORELECTRIC SHOCK,DO NOT
EXPOSETHIS APPARATUSTO
RAINOR MOISTURE.
SEEINSTRUCTION BEFORE
USING!

Apparatenskall anslutas till
jordatuttag nar den ansluts
tillett natverk

MODEL

SERIAL

Channel B+

NO USING

CHANNEL A

GND

1

3

2

INPUT

FROM

SOURCE

+ +

SHIELD SHIELD

CH-2

LINE

2

1

3

OFF ON

BALANCED
INPUT

LINE

2

1

3

OFF ON

CH-1

BRIDGEDINPUT

BRIDGED

STEREO

PARALLEL

(MONO)

6. CAUTION FOR APPLICATION

6.1 General Application Instruction

The following instructions describe the common ways to install your MAC 2.2/2.3/2.4 stereo power amplifier
into a sound application system:

1. First, turn off power switch before connection.

2. Refer to chapter 5 for speaker connection

3. MAC 2.2/2.3/2.4 stereo power amplifier may be operated in one of the three modes, please slide the mode
selector (12) for the specific operating mode.

Channel A+

+

NO USING

9

6.2 Caution for Speaker Connection

The output capacity of MAC 2.2/2.3/2.4 stereo power amplifier is very high, be sure to use a speaker system that has
sufficient input capacity. If the input capacity of your speaker system is lower than the rated output of the MAC 2.2/

2.3/2.4 stereo power amplifier, you can protect your speakers by connecting a fuse serially between the speaker and
the amplifier as shown below.

ON

OFF

POWER

CH1 CH2

CLIP

CLIP

SIG

SIG

Use the following formula to determine the fuse capacity according to the speaker's input capacity.

Po[W] : Speaker's continuous input capacity (noise or RMS)
R[ ] : Speaker's nominal impedance
I[A] : Required fuse capacity

As to the speaker cable, if you use a long one, use as thick a cable as possible to prevent deterioration of the
damping factor or power loss inside the cable.

7. TECHNICAL SPECIFICATIONS

7.1 Specifications

POWER SPECIFICATIONS

STEREO MODE
(Both channels driven)

20Hz~20KHz

Bridge Mono Mode

20Hz~20kHz

ELECTRICAL SPECIFICATIONS

INPUT SENSITIVITY

INPUT IMPEDANCE

2Ohms

4Ohms

8Ohms

8Ohms

4Ohms

(+)
(-)

Output

2

Po=I R I= Po/R

MAC 2.2

480

300

205

560

800

600W

1.15V(+3.4dBu)

10K Unbalanced 20K Balanced

Fuse

+

Speaker

­System

MAC 2.3

800

450

310

900

1400

900W

1.15V(+3.4dBu)

MAC 2.4

1400

750

575

1500

2500

1500W

1.15V(+3.4dBu)

FREQUENCY RESPONSE
(at 10dB belowrated output power)

VOLTAGE GAIN

DISTORTION(SMPTE-1M)

S/N ratio

GENERAL SPECIFICATIONS

PROTECTIONS

CONTROLS

INDICATORS

CONNECTORS

POWER SUPPLY

DIMENSIONS

WEIGHT

25Hz~25KHz +0/-1dB

-3dB points: 5Hz~50KHz

30dB

<0.03%

32dB 34dB

<0.03% <0.03%

100dB 100dB 100dB

600W

900W

1500W

Full short circuit,open circuit, thermal, ultrasonic, and RF protection stableinto reactive
or mismatched loads,turn ON/OFF, muting, tried crowbar.

Front: AC switch 40-detect input level controlfor each channel.
Rear: stereo/ parallel/bridged selector, 30Hz filter selector clip ON/OFF selector.

SIGNAL: 2 green LED

POWER:1BlueLED

CLIP: 2 red LED

PROTECTION: 1 redLED

INPUT : Active balanced XLR and 1/4"(6.3mm)TRS
OUTPUT: "Touch-proof" binding postsand speak-on jacks.

Available for 110-120V or 220~240V AC, 50/60Hz

483(W) 400(D) 88.8(H)mm

14.4kg 16.54kg 19.02kg

10

7.2 Block Diagram

OUTPUT

CH-A

MONO

BRIDGED

PAR ALL EL

OUTPUT

CH-B

PWR

INDR

PWR AMP

DIF

LA

TURN-ON CIRCUIT SHOCK

DC OFFSET

MODE

DC SERVO

OVER TEMP

AUTORAMP

+/-

CIRCUIT

SHORT

TRANSIENTS

CURRENT LIMITER

TURN-ON/TURN-OFF

PWR AMP

DIF

LA

OPTION

BINDING POST

TERMINALS

ACTIVE

CH-A

CLIP

CH-B

CH-A

SIG

CH-B

AMP

POWER TRANS

CH-A

AC PWR

DETECTOR

CH-B

IN-RUSH

FANS

2-SPEED

PROT&PRE

CURRENT

30Hz-9dB

E.R

INPUT

CH-A

LINK

SUB WOOFER

1.15VRMS

+4dB

(OPTION)

15Kohm

BALANCED

30Hz-9dB

E.B

INPUT

CH-B

LINK

POWER

SWITCH

AC POWER

120V/220V/230V

(OPTION)

/240V 50/60Hz

CIRCUIT

BREAKER

NOTICE

:XLR CONNECTOR

:1/4" PHONE JACK

CONNECTOR

:SPEAKON

11

7. WARRANTY

1. WARRANTY REGISTRATION CARD

To obtain Warranty Service, the buyer should first fill out and return the enclosed Warranty Registration Card within
10 days of the Purchase Date.

All the information presented in this Warranty Registration Card gives the manufacturer a better understanding of
the sales status, so as to purport a more effective and efficient after-sales warranty service.

Please fill out all the information carefully and genuinely, miswriting or absence of this card will void your warranty
service.

2. RETURN NOTICE

2.1 In case of return for any warranty service, please make sure that the product is well packed in its original shipping
carton, and it can protect your unit from any other extra damage.

2.2 Please provide a copy of your sales receipt or other proof of purchase with the returned machine, and give detail

information about your return address and contact telephone number.

2.3 A brief description of the defect will be appreciated.

2.4 Please prepay all the costs involved in the return shipping, handling and insurance.

3. TERMS AND CONDITIONS

3.1 warrants that this product will be free from any defects in materials and/or workmanship for a period

LTO

of 1 year from the purchase date if you have completed the Warranty Registration Card in time.

3.2 The warranty service is only available to the original consumer, who purchased this product directly from the
retail dealer, and it can not be transferred.

3.3 During the warranty service, may repair or replace this product at its own option at no charge to you for

LTO

parts or for labor in accordance with the right side of this limited warranty.

3.4 This warranty does not apply to the damages to this product that occurred as the following conditions:

Instead of operating in accordance with the user's manual thoroughly, any abuse or misuse of this product.

Normal tear and wear.

The product has been altered or modified in any way.

Damage which may have been caused either directly or indirectly by another product / force / etc.

Abnormal service or repairing by anyone other than the qualified personnel or technician.

And in such cases, all the expenses will be charged to the buyer.

3.5 In no event shall be liable for any incidental or consequential damages. Some states do not allow the exclu-

LTO

sion or limitation of incidental or consequential damages, so the above exclusion or limitation may not apply to you.

3.6 This warranty gives you the specific rights, and these rights are compatible with the state laws, you may also
have other statutory rights that may vary from state to state.

12

SEIKAKU TECHNICAL GROUP LIMITED

SEKAKU ELECTRON INDUSTRY (H.K.) CO., LTD.

No. 1, Lane 17, Sec. 2, Han Shi West Road, Taichung 40151, Taiwan

http://www.altoproaudio.com Tel: [phone]

email: [e-mail] Fax: [phone]

All rights reserved to ALTO. All features and content might be changed

without prior notice. Any photocopy, translation, or reproduction of part of this

manual without written permission is forbidden. Copyright 2005 SEIKAKU GROUP

c

NF01893-1.2