Power Base Series; 1 Welcome; 1.2 Features- Page 7

Power Base Series

  Power Amplifiers

Page 7

1 Welcome

Congratulations on choosing a 

Power Base amplifier.

Power Base amplifiers are compact, professional ste-
reo power amplifiers engineered to meet the most de-
manding sound reinforcement needs. They compare
very favorably to more expensive amplifiers, providing
uncolored sound and signal-to-noise ratios commonly
associated with recording studios.

This manual will help you successfully install and use
your amplifier—we strongly recommend you read all
instructions, warnings and cautions. If you plan to oper-
ate in one of the two mono modes, be sure to read Sec-
tion 2.2. Also for your protection, please save your bill
of sale as it is your 

official proof of purchase.

1.2 Features

❏

Rugged, professional power amplifier built for the road.
Mounts in a standard 19 inch (48.3 cm) rack.

❏   

Crown’s patented 

grounded bridge circuitry gener-

ates large voltage swings while avoiding electrical
stress on the output stages. This results in low distortion
and high reliability.

❏

Front panel power switch with turn-on delay for loud-
speaker protection.

❏

Patented Output Device Emulation Protection (

ODEP

®

)

keeps the amplifier working when others would fail.

❏

High damping factor provides superior control over low
frequency drivers for a clean, accurate low end.

❏

Safe with any load. Bridge-Mono and Parallel-Mono
modes offer optimal load-matching performance.

❏

Complete protection against shorted outputs, mis-
matched loads, overheating, DC input/output and high-
frequency overload; full internal fault protection.

❏

Balanced phone jack inputs with internal three-position
sensitivity switch. Optional XLR or barrier block input
connectors are available with the 

MT-XLR or MT-BB ac-

cessories.

❏

Ground lift switch is provided to isolate the chassis
ground from the phone jack input ground.

❏

Efficient heat sinks and self-contained forced air cool-
ing system dissipate heat quickly and evenly for extra
amplifier protection and greater power output.

❏

Three year “No-Fault” full warranty and guaranteed
specifications protect your investment.

Fig. 1.1  Power Base Front and Back Panels

CAUTION:
THIS COVER IS NECESSARY FOR
EFFICIENT COOLING OF THE AMPLIFIER.
REMOVE ONLY TO ACCESS GAIN SWITCH.

REG. U.S. PAT. OFF.

4,330,809
4,611,180

CAUTION: TURN OFF AMPLIFIER

 BEFORE CHANGING THIS SWITCH!

STEREO

BRIDGE

MONO

PARALLEL

MONO

BRIDGE-MONO WIRING

TURN AMPLIFIER OFF.

SET STEREO/MONO
SWITCH TO
BRIDGE-MONO.

OUTPUT ACROSS
RED TERMINALS
ONLY. (CH-1
IS POSITIVE.)

PARALLEL-MONO WIRING

TURN AMPLIFIER OFF.

SET STEREO/MONO SWITCH
TO PARALLEL-MONO.

ADD JUMPER (14
GAGE OR LARGER)
ACROSS RED TERMINALS.

OUTPUT ACROSS CH-1
TERMINALS ONLY.

1

2

3

4

1

2

3

CH-2

CH-1

+

–

–

+

THIS AMPLIFIER IS EQUIPPED WITH SELECTABLE INPUT SENSITIVITY. REMOVE COVER PLATE (ABOVE) TO ACCESS SENSITIVITY SWITCH.

CH-2

INPUT GROUND LIFT

(AFFECTS PHONE INPUTS ONLY.)

(MONO)

MODEL:  POWER-BASE™ 3   12.5 AMPS
      AC VOLTS: 120                60 Hz

MAXIMUM OUTPUT:  700 WATTS
PER CHANNEL INTO 4 OHMS AT 1 KHz
WITH NO MORE THAN 0.1% THD.

INPUT

GAIN

CH-1

INPUT

GAIN

CLASS 2
OUTPUT
WIRING

 REQUIRED.

OUTPUTS

CAUTION: 

TO PREVENT ELECTRIC

SHOCK DO NOT REMOVE TOP OR BOTTOM
COVERS. NO USER SERVICEABLE PARTS
INSIDE. REFER SERVICING TO QUALIFIED
SERVICE PERSONNEL. DISCONNECT POWER
CORD BEFORE REMOVING REAR COVER
PLATE TO ACCESS SENSITIVITY SWITCH.

ATTENTION: 

DÉBRANCHER AVANT

D'OUVRIR.

WARNING: 

TO

REDUCE THE RISK OF
FIRE OR ELECTRIC
SHOCK, DO NOT EXPOSE
THIS EQUIPMENT TO
RAIN OR MOISTURE.

LIFT

PUSH TO RESET

BALANCED

INPUT WIRING

+

–

TIP

RING

SLEEVE

GND

UNBALANCED
INPUT WIRING

+

TIP

SLEEVE

GND

0

1

2

3

4

5

6

7

8

9

10

11

12

0

1

2

3

4

5

6

7

8

9

10

11

12

®

INTERNATIONAL, INC.

ELECTRONIC EQUIPMENT

ELKHART, IN 46517
MADE IN U.S.A.

SERIAL NUMBER

0000

000000

PR

E

S

S

R

E

S

E

T

OFF

POWER

Removable grille

and dust filter

Power

Indicator

Power
Switch

Stereo/Mono

Switch

Ch.1

¼ Inch

Phone

Input 

Ch.2

¼ Inch

Phone

Input 

Ground

Lift

Switch

Ch.1

Level

Control 

Ch.2

Level

Control 

5-Way Binding Post

Output Connectors

Access

Cover

Reset

Switch

(Power Base–3 Only)

Power

Cord

1.1 Unpacking

Please unpack and inspect your new amplifier for any
damage that may have occurred during transit. If dam-
age is found, notify the transportation company imme-
diately. Only you, the consignee, may initiate a claim
with the carrier for damage resulting during shipment.
Even if the unit arrived in perfect condition, as most do,
save all packing materials so you will have them if you
ever need to transport the unit. 

NEVER SHIP THE

UNIT WITHOUT THE FACTORY PACK.