AMPEG PB250 Owner's Manual

Owner ’s Guide for the

Amp Head

Made with Pride in the U.S.A. by Ampeg

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ABLE OF CONTENTS

Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Important Safeguards and Precautions . . . . . . . . . .3
The Front Panel Controls and Their Use . . . . . . . .4
The Rear Panel . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . .6
System Block Diagram . . . . . . . . . . . . . . . . . . . . . .7
Technical Specifications . . . . . . . . . . . . .back cover

PB250

PortaBass Amp Head

IMPORTANT SAFETY INSTRUCTIONS

• READ, FOLLOW, HEED, AND KEEP ALLINSTRUCTIONS AND WARNINGS.

• DO NOTOPERATE NEAR ANY HEATSOURCE AND DO NOT BLOCK ANY VENTILATION OPENINGS ON THIS APPARATUS. FOR PROPER OPERATION, THIS UNIT REQUIRES 3”

(75CM) OF WELL VENTILATED SPACE AROUND HEATSINKS AND OTHER AIR FLOW PROVISIONS IN THE CABINET.

• DO NOTUSE THIS APPARATUS NEAR SPLASHING, FALLING, SPRAYING, OR STANDING LIQUIDS.

• CLEAN ONLY WITH LINT-FREE DAMP CLOTH AND DO NOTUSE CLEANING AGENTS.

• ONLY CONNECT POWER CORD TO APOLARIZED, SAFETYGROUNDED OUTLETWIRED TO CURRENT ELECTRICAL CODES AND COMPATIBLE WITH VOLTAGE, POWER, AND

FREQUENCY REQUIREMENTS STATED ON THE REAR PANEL OF THE APPARATUS.

• PROTECTTHE POWER CORD FROM DAMAGE DUE TO BEING WALKED ON, PINCHED, OR STRAINED.

• UNPLUG THE APPARATUS DURING LIGHTNING STORMS OR WHEN UNUSED FOR LONG PERIODS OF TIME.

• ONLY USE ATTACHMENTS, ACCESSORIES, STANDS, OR BRACKETS SPECIFIED BY THE MANUFACTURER FOR SAFE OPERATION AND TO AVOID INJURY.

• THIS APPARATUS DOES NOTOPERATE NORMALLYAND REQUIRES SERVICE WITH ANY PHYSICAL DAMAGE FROM IMPACT OR ANY EXPOSURE TO MOISTURE.

• SERVICE MUSTBE PERFORMED BY QUALIFIED PERSONNEL.

• OUR AMPLIFIERS ARE CAPABLE OF PRODUCING HIGH SOUND PRESSURE LEVELS. CONTINUED EXPOSURE TO HIGH SOUND PRESSURE LEVELS CAN CAUSE PERMA-

NENT HEARING IMPAIRMENTOR LOSS. USER CAUTION IS ADVISED AND EAR PROTECTION IS RECOMMENDED IF UNIT IS OPERATED AT HIGH VOLUME.

CAUTION

RISK OF ELECTRIC SHOCK

DO NOT OPEN

WARNING: TO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK, DO NOT EXPOSE
THIS APPARATUS TO RAIN OR MOISTURE. TO REDUCE THE RISK OF ELECTRIC
SHOCK, DO NOT REMOVE COVER. NO USER-SERVICEABLE PARTS INSIDE. REFER
SERVICING TO QUALIFIED SERVICE PERSONNEL.

PRECAUCION

RIESGO DE CORRIENTAZO

NO ABRA

PRECAUCION: PARA REDUCIR EL RIESGO DE INCENDIOS O DESCARGAS ELECTRICAS, NO PER­MITA QUE ESTE APARATO QUEDE EXPUESTO A LA LLUVIA O LA HUMEDAD. PARA DISMINUOIR EL
RIESGO DE CORRIENTAZO. NO ABRA LA CUBIERTA. NO HAY PIEZAS ADENTRO QUE EL USARIO
PUEDO REPARAR DEJE TODO MANTENIMIENTO A LOS TECHNICOS CALIFICADOS.

ATTENTION

RISQUE D'ELECTROCUTION

NE PAS OUVRIR

ATTENTION: PROTÉGEZ CET APPAREIL DE LA PLUIE ET DE L'HUMIDITÉ AFIN D'ÉVITER TOUT
RISQUE D'INCENDIE OU D'ÉLECTROCUTION. POUR REDUIRE D'ELECTROCUTION NE PAS ENLEVER
LE COUVERCLE. AUCUNE PIECE INTERNE N'EST REPRABLE PAR L'UTILISATEUR. POUR TOUTE
REPARATION, S'ADRESSER A UN TECHNICIEN QUALIFIE.

"IT IS NECESSARY FOR THE USER TO REFER TO THE INSTRUCTION MANUAL"
“ES NECESARIO QUE EL USUARIO SE REFIERA AL MANUAL DE INSTRUCCIONES.”
"REFERREZ-VOUS AU MANUAL D'UTILISATION"

EXPLANATION OF GRAPHICAL SYMBOLS:
EXPLICACION DE SIMBOLOS GRAFICOS:
EXPLICATION DES SYMBÔLES GRAPHIQUES:

"DANGEROUS VOLTAGE"
“VOLTAJE PELIGROSO”
"DANGER HAUTE TENSION"

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Thank you for choosing the Ampeg PB250 PortaBass Amp Head. The
PB250 features Ampeg’s radical new Micro Dynamic Technology power
amp circuitry. This gives you the ultimate combination of power, tone,
and portability in a small, lightweight package.

In order to obtain maximum performance and enjoyment from your
new Ampeg amplifier, please read these instructions prior to its use.

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PB250

PortaBass Amp Head

In the world of high performance bass amps, Ampeg amplifiers stand alone. In true Ampeg tradition, the PB250
offers you more power , performance and tone than any other bass amplifier in its class. The outstanding features
which set your new amplifier apart from the competition are listed below.

• MDT POWER AMP: Micro Dynamic Technology amplifier circuitry provides maximum power in a
small lightweight package – the efficiency of this design eliminates the need for heavy heat sinks,
transformers and filter capacitors

• FOUR BAND ROTARY EQ: Four bands of equalization and shift controls for the Low and High Mid
provides optimum tone control

• ULTRA LOW, ULTRA HIGH SWITCHES: Enhances flexibility and tone control

• EFFECTS LOOP: Send and Return jacks are combined with an Effects Blend control for virtually

noise-free use of your favorite effects

• TRANSFORMER BALANCED LINE OUTPUT: XLR jack with level control, ground lift, and a
pre/post-EQ switch – for patching into house consoles, mixing boards, or external power amplifiers

• SPEAKON®AND 1/4” SPEAKER OUTPUT JACKS: Compatible with either type of connecting cable

• MADE WITH PRIDE IN THE U.S.A.

Features

Important Safeguards and Precautions:

All Ampeg products are designed for continuous safe operation, as long as common sense is used and steps are taken to help avoid certain

problems. Abiding by the following rules can help prevent damage to your amplifier, yourself, and others.

• The amplifier is equipped with a three-pronged AC power cord. To reduce the risk of electrical shock, NEVER remove or otherwise
attempt to defeat the ground pin of the power cord.

• Connect the amplifier ONLY to a properly grounded AC outlet of the proper voltage for your amp.

• Avoid sudden temperature extremes, rain and moisture. Also, avoid sudden and intense impact. (If the unit has been subjected to

any of the preceding abuses, have it looked at by an authorized service center.)

• NEVER set the amplifier on a support that might give out under its weight.

• Always keep the total speaker impedance at or above the rated load.

• Unplug the amplifier before cleaning it. NEVER spray liquid cleaners onto the amplifier. Wipe it with a slightly dampened, lint-free

cloth to remove dirt and film.

• Do not use the amplifier if it has sustained damage to the chassis, controls, or power cord. Refer the unit to an authorized service
center for inspection.

• Amplifiers capable of producing high volume levels are also capable of inflicting permanent hearing loss or damage, if the exposure
to such levels is prolonged. Such damage is progressive and irreversible! Consider using quality hearing protection devices.

Declaration Of Conformity

#41, Effective 02-01-2002

Manufacturer’s Name: SLM Electronics

Production Facility: 11880 Borman Drive, St. Louis, MO 63146, USA
Production Facility: 700 Hwy 202 W, Yellville, AR 72687, USA
Shipping Facility: 1400 Ferguson Ave., St. Louis, MO 63133, USA
Office Facility: 1400 Ferguson Ave., St. Louis, MO 63133, USA

Product Type: Audio Amplifier
Complies with Standards:

LVD: 92/31/EEC, 93/68/EEC, & 73/23/EWG
Safety: EN60065
EMC: EN55013, EN55020, EN55022, EN61000-3-2,

& EN61000-3-3

Supplementary information provided by:

SLM Electronics - R & D Engineering

1901 Congressional Drive, St Louis, MO 63146, USA

Tel.: [phone], Fax: [phone]

Speakon®is a registered trademark of Neutrik USA