American audio GX-300 User Manual

Power

ON

GX-300

American Audio™

Professional Stereo Amplifier

American Audio®

Professional Power Amplifi er

GX-300

Los Angeles Ca. 90058

4295 Charter Street

American Audio®

Power Bridge Stereo Clip Signal Clip Signal

User Instructions

Ch A Ch B

Min Max Min Max

Revised 5/01

anced RCA jacks on the rear of amplifi er. At this point chose the run

the amplifi er in BRIDGE or STEREO mode. (Stereo is the default

setting, see page 5.)

4. Connect the left and right speakers to the amplifi ers output ter-

minals. Use either the 1/4" (6.35 mm) jacks or the 3-way banana

binding post.

GX-300™ Power Amplifier Instructions page 2

1/4" (6.35 mm) phono jacks, 3-pin balanced XLR jacks, or unbal-

Quick Start: The following instructions are provide as a guide for

PROTECTION............................................................................................................................................................11

SPECIFICATIONS.......................................................................................................................................................12

RESET BREAKER.........................................................................................................................................................11

STEREO/BRIDGED MONO........................................................................................................................................11

OUTPUTS....................................................................................................................................................................8

LOW-CUT FILTER......................................................................................................................................................11

REAR PANEL..............................................................................................................................................................6

INPUTS........................................................................................................................................................................7

those user already familiar with the basic operation of amplifi ers.

1. Be sure you amplifi er and all other audio equipment is power

down before attempting any type of connection. The amplifi er

power button is located on the lower left-hand side of the front of

amplifi er.

2. Securely mount the amplifi er in standard 19" rack, or position it

on a solid surface.

3. Connect the left and right output signal a mixer, preamp, or pro-

cessor to the amplifi ers inputs. Use either balanced/unbalanced

QUICK START....................................................................................................................................................................2

SAFETY PRECAUTION....................................................................................................................................................3

FRONT PANEL............................................................................................................................................................5

WARNING: The red banana output terminals on the rear of the

unit marked with the symbol are dangerous when active. Exter-

nal wiring connected to these terminals requires installation by a

qualifi ed person, or make use of preconstructed speaker cables

available at a local professional sound retailer.

5. Connect the amplifi er to a power outlet with a matching power

supply.

6. Turn on all audio components except the amplifi er. Be sure both

Channel A and Channel B volume controls are turned all the way

down (full counter-clockwise), and turn on main power.

7. Turn the mixer or other audio components up and adjust the

amplifi er levels. The green signal LED's on the face of the unit will

indicate signal is being received.

CONTENTS

5. Do not attempt to operate this unit if the power cord has been

frayed or broken. Please route your power cord out of the way

of foot traffic.

6. Do not attempt to remove or break off the ground prong

from the electrical cord. This prong is used to reduce the

risk of electrical shock and fire in case of an internal short.

7. Always have the front gain controls set to their lowest level

GX-300™ Power Amplifier Instructions page 3

1. Be sure to save the packing carton in the unlikely event this

unit may have to be return the unit for service.

2. Read all documentation before attempting to operate your

new amplifier. Please save all you documentation for future

reference.

3. To reduce the risk of fire or electrical shock, do expose this unit

to rain, moisture, water or other liquids.

4. Be sure that the local power outlet match that or the required

voltage for your amplifier.

AUTHORIZED AMERICAN AUDIO® DEALER.

INSIDE. REFER ALL SERVICE TO YOUR

The lightning flash with an arrow triangular

symbol is intended to alert the user to the

presence of non insulated “dangerous volt-

age” within the products enclosure, and

may be of sufficient magnitude to constitute

a risk of electric shock.

The exclamation point triangular symbol is

intended to alert the user to the presence

of important operating and maintenance

(servicing) instructions in the user manual

accompanying the CD player.

OF LESS THAN 2 OHMS. OR ANY

COMBINATION OF SPEAKERS THAT

TOGETHER ARE LESS THAN 2

OHMS!

USING ONE SPEAKER, IT MUST BE

RATED AT 4 OR MORE OHMS.

USING TWO SPEAKERS, THEY MUST

RATED EACH AT 4 OR MORE OHMS.

USING THREE SPEAKERS, THEY

MUST BE RATED EACH AT 8 OR

MORE OHMS.

CAUTION: TO REDUCE THE RISK OF ELECTRIC

THERE ARE NO USER SERVICEABLE PARTS

SHOCK, DO NOT REMOVE THE COVER.

Risk of electric shock

Do not open -

CAUTION

FOR OPTIMUM PERFORMANCE AND

RELIABILITY DO NOT PRESENT THE

AMPLIFIER WITH A SPEAKER LOAD

connection.

9. Do not block the units cooling vents or fan intake. If this unit is

being used in an extremely dusty or smoky environment, the

unit should be blown through on a regular basis.

10.Do not remove the top cover under any conditions. There are

no user serviceable parts inside.

11.Do not drive the inputs with a signal level greater than that

required to drive equipment to full output.

12.Do not try to run the input signal of an amplifier by the

output of any other amplifier.

13.Never ground a RED (positive) terminal.

14.Disconnect the unit’s main power when left unused for long

periods of time.

during initial power-up to prevent speaker damage .

8. Disconnect from main power before making any type of

Important Precautions

NESOUMETTE JAMAIS L’AMPLIFICATEUR

A UNE CHARGE D’IMPEDANCE TOTALE

INFERIEURE A 2 OHMS, NI AVEC UN H.P.

NI EN COMBINAISON DES H.P.

AVEC UN H.P., IL FAUT UNE CHARGE

D’IMPEDANCE MINIMUM DE 2 OHMS.

AVEC DEUX H.P., FAUT POUR CHAOUN

UNE CHARGE D’IMPEDANCE MINIMUM

DE 4 OHMS.

AVEC TROIS H.P., FAU T P O UR CHAOUN

UNE CHURGE D’IMPEDANCE MINIMUM

DE 8 OHMS.

POUR ASSURER LA FIABILETE ET

OBTENIT UNE PERFORMANCE OPTIMALE,

Stereo Operation.

14. Sign al and Clip LED indicators on the front panel detail input

signal integrity.

15. Front panel power switch and power LED indicator.

GX-300™ Power Amplifier Instructions page 4

12. Two rackspace case design.

13. Mo de monitor LED's on the front panel detail Bride-Mono or

11. Li gh t weight only 16 Lbs (4.1 Kgs)

10. Two year limited warranty.

Features

1. Bridge-Mono/Stereo mode switch. This switch allow the ampli-

fier operating mode to toggle between stereo and bride-mono

mode.

2. Built-in protection circuitry: DC output protection, Overload

protection (clip limiting), and Short circuit protection.

3. Variable speed cooling fan for optimal performance and cool-

ing.

4. 19" (48.3 cm) rackmountable case design.

5. 9" (220 cm) shallow case design, allowing this amp to be

installed in a shallow rack, stacked on top of each other, or

stacked on a cart.

6. Three different input options; 1/4" balanced/unbalanced jacks,

balanced XLR jacks, and Unbalanced RCA jacks.

7. Tw o different output options (speaker connections); 1/4" jacks

or 3-way banana style binding post.

8. Dedented channel gain controls on the front panel.

9. Rear panel 5 amp reset button (breaker type).

comments or suggestions.

any question should you encounter problems during your set

up or initial operation. For service related issue please contact

American Audio® Technical Support Team. Service Hours are

Monday through Friday 9:00 a.m. to 5:00 p.m. Pacific Standard

Time.

Voice: [phone]

Fax: [phone]

E-mail: [e-mail]

You may also visit us on the web at www.americandj.com for any

19” rack. The front panel provides four holes used to screw the

unit into a rack.

Customer Support: For assistance beyond that which is cover

in this manual, American Audio® provides a toll free customer

support line, to provide additional set up help and to answer

stand. When a cart is used, use caution when moving

the cart/unit combination to avoid injury from tip-overs.

Cart Installation: Use only with a stable cart or

Installation: This amplifier is designed to mount in a standard

unpacking, inspect the amplifier for any type of damage that may

have occurred during shipping or transit. If you notice any type of

damage notify your dealer immediately for instructions.

Unpacking: Carefully open and unpack your amplifier. After

information concerning the proper any safe operation of your new

amplifier.

best and highest quality products at an affordable price. Please

read and understand this manual completely before attempting

to operate your new amplifier. This booklet contains important

Introduction: Congratulations and thank you for purchasing the

tation of American Audio’s continuing commitment to produce the

American Audio® GX-300™ amplifier. This amplifier is a represen-

General Information

1. POWER BUTTON -

This is used to activate the amplifier's main power. When main

power is activated it will indicated the Power LED (2).

2. POWER LED -

This green LED will glow when the amplifier is turned on, indicat-

ing main power is traveling through the unit.

3. BRIDGE LED -

This green LED will glow when the amplifier is in Mono-Bridge

mode. For more information on operating in Mono-Bridge mode

see page .

4. STEREO LED -

This green LED will glow when the amplifier is in Stereo mode.

For more information on operating in Stereo mode see page .

5. CHANNEL A CLIP INDICATOR -

This red LED will glow begin to flash at the amplifiers clipping

point, the point when the output signal begins to distort. Under

heavy clipping lower the input gains (Diagram 8) to reduce the risk

of damage to your speakers and amplifier. This LED will also glow

constantly when channel A goes in to protect mode. In protect

FRONT PANEL

Power

1 6891075432

ON

GX-300

American Audio™

GX-300™ Power Amplifier Instructions page 5

signal to the speakers will terminated.

9. CHANNEL B SIGNAL INDICATOR -

This Green LED will glow when there is an input signal present.

10. CHANNEL B GAIN CONTROL -

This knob adjust the channel one volume output to the speakers

connect to channel one.

mode the output signal to the speakers will terminated.

6. CHANNEL A SIGNAL INDICATOR -

This Green LED will glow when there is an input signal present.

7. CHANNEL A GAIN CONTROL -

This knob adjust the channel one volume output to the speakers

connect to channel one.

8. CHANNEL B CLIP INDICATOR -

This LED comes on at the amplifiers clipping point, the point when

the output signal begins to distort. Under heavy clipping lower the

input gains (Diagram 10) to reduce the risk of damage to your

speakers and amplifier. This LED will also glow constantly when

channel B goes in to protect mode. In protect mode the output

Professional Stereo Amplifier

Power Bridge Stereo Clip Signal Clip Signal

Ch A Ch B

Min Max Min Max

Diagram 1

13. Channel B 1/4" Input -

This jack is a balanced or unbalanced 1/4" phono plug input jack.

Connect a mixer's channel "B" or channel two output signal to this

input jack. Tip is positive.

14. Channel A 1/4" Input -

This jack is a balanced or unbalanced 1/4" phono plug input jack.

Connect a mixer's channel "A" or channel one output signal to this

input jack. Tip is positive.

15. Unbalanced RCA Input -

These jacks are standard unbalanced RCA input jacks. The right

channel jack is indicated with red and left is indicated with white.

16. Bridge-Mono/Stereo MODE Switch -

This switch changes the amplifier operating mode from stereo to

bridge-mono. The amplifier's default operating mode is stereo.

GX-300™ Power Amplifier Instructions page 6

11. Channel B XLR Input -

Connect a mixer's balanced channel "B" or channel two output

signal to this balanced XLR input jack. Pin two is negative, Pin

one is ground, Pin three is ground.

12. Channel A XLR Input -

Connect a mixer's balanced channel "A" or channel one output

signal to this balanced XLR input jack. Pin two is negative, Pin

one is ground, Pin three is ground.

11 171615141312 232221201918

REAR PANEL

17. COOLING FAN -

This is a variable speed cooling fan. Never block the fan in any

way or mount in an enclose rack, doing so may cause the ampli-

fier to overheat and fail.

18. Channel 2 Speaker Output/3 Way Binding Post -

Connect your channel two speakers to channel two output.

19. Channel 1 Speaker Output/3 Way Binding Post -

Connect your channel one speakers to channel one output.

20. Channel 2 1/4" Speaker Output -

Connect your channel two speakers to channel two output.

21. Channel 1 1/4" Speaker Output -

Connect your channel one speakers to channel one output.

22. RESET BREAKER -

This is a 5 amp breaker, that will clip when ever the unit exceeds

the maximum of power drawl.

23. A/C Power Input -

Never plug your amplifier in to a wall outlet that does not match

the required voltage of your amplifier, serious damage may occur

to your unit.

Diagram 2

Tip =

Ring = =

Sleeve = =

+ =

GX-300™ Power Amplifier Instructions page 7

1/4" Jack XLR

SHIELD

-

INPUTS

The GX-300™ allows for three types of input connector per a channel, a XLR jacks for balanced connections and unbalanced 1/4”

and RCA jacks. Use these connection to connect the output signal from a mixer, cross-over or EQ to your GX-300 amplifier. The XLR

connection is recommended for cable runs longer that 20ft. When building your own XLR cables follow the pin configuration describe

below for proper connections. For cable runs shorter than 20Ft. you may choose the 1/4” input option. The 1/4” input option may be

a little more convenient for most user due to the abundant supply of prefabricated cables on the market. You may also use the two

different types of input cables to jump a parallel connection to another amp. For Example: Connect a XLR cable to the input of channel

one. You may now connect a 1/4” cable to the input put jack of channel one and jump that cable to the input of another amp.

INPUT

0

+

-

+

BALANCED

GND

Pin 1

Pin 3

PIN 2: Negative data complement (-, Inverted)

PIN 3: Positive data (+, Inverted)

Jack(6.35 mm)

Pin 2

XLR Pin Configuration:

US ITT Standard

PIN 1: Ground / Return / 0v

SHIELD

+

INPUT

+

0

GND

UNBALANCED

Diagram 4

Bridge-Mono Connections:

Mono bridge operation connections will follow the above descriptions however,

when operating in mono bridge operation the speaker connections will run between

the two positive (red) leads. Use channel two positive (red) output terminal for

negative and the channel one positive (red) output terminal for positive connection.

(See page 9 Diagram 8)

©

American DJ Supply

®

- www.americandj.com - GX-300™ Power Amplifier Instructions page 8

the banana jacks into the caps of the binding post, be sure that the banana jack is

inserted securely to avoid the risk of it popping out.

the red and black caps on the binding post are tighten down completely. Insert

Banana Plug:

When connecting your speakers to the amplifier using banana jacks; Be sure that

damage to your amplifier, be sure that the wire connected to one binding post does

not come in contact with that of another.

the red and black caps on the binding post, be sure not to completely remove or

unscrew the red and black caps. Insert the spade connector in to the binding post

and tighten the caps down on the spade connector. To reduce the risk of shock or

Spade Connector: (Diagram 6)

When connecting your speakers to the amplifier using spade connector; Unscrew

does not come in contact with that of another.

cap down on the wire. To reduce the risk of shock or damage to your amplifier, be sure that the wire connected to one binding post

When connecting your speakers to the amplifier using bare wire; Unscrew the red and black caps on the binding post, be sure not

to completely remove or unscrew the red and black caps. Strip back the wire insulation 1/2” (13mm). Insert the bare wire into the

hole that was reveled by unscrewing the binding post cap. After inserting the wire into the binding post hole, screw the binding post

out of phase, that can cause a loss of bass response.

Bare Wire Connections: (Diagram 5)

two output for stereo mode or across the red terminals of Channels one and two for Mono Bridge Mode. Important Notice: Although

a speaker will operate with the positive and negative leads plugged into either terminal on the amplifier binding post, be sure to plug

the negative lead into the black terminal and positive lead into the red terminal. Ensuring proper polarity will avoid your speakers being

OUTPUTS:

Connect your speakers to the binding post outputs in the rear of the amp. The speaker wire may be connect by bare wire (directly

connected usually for permanent connections), banana plug, or spade connector. Connections are made to Channel one and Channel

Diagram 6

Diagram 5

Typical Speaker Output Binding Post.

Insert spade connector into the binding

post and tighten.

Typical Speaker Output Binding Post.

Insert bare wire into the binding post.

TYPICAL MONO BRIDGE SET-UP

Diagram 8

4 OHM MINIMUM

SPEAKERS

GX-300™ Power Amplifier Instructions page 9

8 OHM MINIMUM

SPEAKERS

Typical Stereo Output Connections

Diagram 7

or

4 OHM MINIMUM

SPEAKERS

Typical Speaker

Connect to GX-300™ Channel One Output

GX-300™ Power Amplifier Instructions page 10

GX-300™ (Rear View)

Diagram 9

Typical Stereo Set-Up

Typical Speaker

Connect to GX-300™ Channel Two Output

Typical DJ Mixer

SHORT CIRCUIT PROTECTION

The Output Short circuit protects the output devices from short circuits and stressful loads.

THERMAL PROTECTION

A single variable-speed fan provides adequate cooling. But if the heatsink temperature exceeds 90C., the amplifier will mute until

the amplifier cools down.

INPUT/OUTPUT PROTECTION

The input circuits are isolated by 10k resistors. An ultrasonic network uncouples RF from the output and helps keep the amplifier

stable with reactive loads.

RESET BREAKER -

This is a 5 amp breaker, that will clip when ever the unit exceeds the maximum of power drawl. If this breaker clips in to protect mode

continuously, stop using the amplifier immediately and contact customer support, the unit my need to be serviced.

GX-300™ Power Amplifier Instructions page 11

clipping. When the signal amplitude decreases enough that clipping ends, the limiter will deactivate and cease its gain reduction.

PROTECTION:

LIMITER

During normal operation, the limiter does not affect the audio signal and is, in fact inaudible. It will allow brief clipping of peaks and will

only activate when continuous, hard clipping occurs. The limiter will then reduce the audio signal enough to minimize the amount of

to regulate your amplifier output.

NORMAL OPERATION:

Page 10/Diagram 9 show you an example of a typical stereo set-up. Connect your inputs into channels one and two of the amplifier.

Connect your speakers to the outputs on the rear of the amplifier. Be sure that your front gain controls are turned down to their lowest

level (full counter-clockwise). Turn your amp on. Turn your input level up. Use your front gain controls to regulate the output volume. Be

sure not to raise the volume to the clip level however, an intermittent clip signal is acceptable.

MONO BRIDGE OPERATION:

Page 9/Diagram 8 give you a description of mono bridge set-up. Be sure you amplifier and all other equipment is shut off. Press the

Stereo/Mono switch to the in position (Page 6/Diagram 2). Connect an input signal to channel one. Connect your speaker across

the red output binding post on the rear of your amplifier (See Page 8 Mono Bridge Set-Up). Turn your equipment on (your amplifier

should be the last piece you turn on). Apply an input signal to your amplifier. Turn channel two gain up. Use the channel one gain

Power Consumption: @

rated output power, 8 ohms

Cooling System:

8A @ 120v AC

1 Dual Speed Fan

and Heatsinks

5A @ 120v AC

GX-300™ Power Amplifier Instructions page 12

7A @ 120v AC

2 Dual Speed Fans

and Heatsinks

Below rated output,

Hum & Noise:

8 ohms

100 dB, unweighted

100 dB, unweighted

Height

Width

Depth

Weight

Frequency Response:

+/- 1db, 1w RMS. 8 ohms

+/- 0.2 db, @ rated output,

8 ohms

1.75 ” (4.4cm)

19 ” (48.3cm)

15.25 ” (40cm)

10 Hz - 40 kHz

20 Hz- 20 kHz

10 Hz - 40 kHz

20 Hz - 20 kHz

25 lbs. (10.5kg)

3.5” (88cm)

19” (48.3cm)

8.86” (220.cm)

16.3 Lbs. (4.1 kg.)

3.5 ” (8.8cm)

19 ” (48.3cm)

15.9 ” (40.5cm)

30 lbs. (13.6kg)

output power, 8 ohms

Input Sensitivity and

Impedance: @ rated

output power, 8 ohms

Dimensions & Weight:

1.5v rms

.775v RMS (0 dBv)

1.0v RMS (0 dBv)

Total Harmonic Distortion:

20Hz-20kHz, @ rated

Less than 0.1%

Less than 0.1%

(Bridge Mode, mono)

4 ohms, 1khz, 1% THD

8 ohms, 1khz, 1% THD

N/A

600 WATTS RMS

N/A

300 RMS PER CH.

1050 WATTS RMS

820 WATTS RMS

2 ohms, 1 khz 1% THD

4 ohms, 1khz, 1% THD

8 ohms, 1khz 1% THD

N/A

280W RMS PER CH.

200W RMS PER CH.

N/A

150W RMS PER CH.

100W RMS PER CH.

540W RMS PER CH.

400W RMS PER CH.

280W RMS PER CH.

Output Power:

SPECIFICA TIONS

MODEL NO:

V-1500 V-2000 MKII

GX-300

and Heatsinks

and Heatsinks

10A @ 120v AC

2 Dual Speed Fans 2 Dual Speed Fans

40A @ 120v AC

10 Hz- 40 kHz

100 dB, unweighted

100 dB, unweighted

20 Hz- 40 kHz

10 Hz- 40 kHz

20 Hz- 40 kHz

31 lbs. (14 kg.)

61.7 lbs. (28 kg.)

3.5 ” (8.8cm)

19 ” (48.3cm)

15.9 ” (40.5cm)

5.25 ” (13.3cm)

19 ” (48.3cm)

15.9 ” (40.5cm)

1.0v RMS (0 dBv)

1.0v RMS (0 dBv)

Less than 0.1%

Less than 0.02%

1100 WATTS RMS

1650 WATTS RMS

800W RMS PER CH.

600W RMS PER CH.

360W RMS PER CH.

1500 WATTS RMS

1400W RMS PER CH.

1010W RMS PER CH.

600W RMS PER CH.

2500 WATTS RMS

V-3000

V-4000

web: www.americandj.com / e-mail: [e-mail]

4295 Charter Street Los Angeles, CA 90058 USA

Part of the American DJ Group of Companies

Tel: [phone] / Fax: [phone]

American DJ World Headquarters:

©American Audio