Ampeg Bass Amplifier B15R User Manual

							OWNER’S GUIDE 
						

							Thank you for selecting the Ampeg B-15R Portaflex Bass Amplifier. Revived from the past and enhanced for the
present, this limited production model offers all of the best features of the 1960’s classic plus more. In order to
get the most out of your new amplifier, please read these instructions before its use. 
FEATURES:
• 0db and -15dB Input Jacks • Tube Bias Select Switch • Patented “Flip Top” Enclosure
• Ultra High / Ultra Low Boosts • Impedance Selector (8/4 Ohms) • Ampeg Vintage 15” Speaker
• Input Gain Control • Line Out/Line In jacks • H.F. Horn w/Level control
• Three Band EQ • XLR Balanced Line Out Jack • 100 watts RMS
• Five Position Mid Freq Select • Line Out Level Control • All Tube Design
• Master Volume Control • Pre/Post Select Switch  • Removable Dolly Board w/Casters
• Half-Power Switch • Ground Lift Switch • Proudly Made In America
OUT
IN
AS
NEEDED
AS
NEEDED
IN INAS
NEEDED ASNEEDED
OUT
OUT
AS
NEEDED ASNEEDED
OUT
IN
AS
NEEDED ASNEEDED
SOME SUGGESTED SETTINGS:
JAZZ:
FUNK:
ROCK:
COUNTRY:
B-15R PORTAFLEX 
						

							B-15R PORTAFLEX
124
3
6791011121358
1,2: INPUT JACKS:Connect the signal cable from your
instrument to either of these jacks: if your bass has
active electronics, its output may be “hotter” than normal
– the -15dB jack is padded to accommodate such sig-
nals. If your bass has normal pickups, use the 0dB jack.
3,4: ULTRA HI / ULTRA LO BOOSTS:Engage these
pushbutton switches to boost the highs or lows as
desired. These switches activate the boosts at their “in”
positions.
5: GAIN CONTROL:Adjust this control to suit your
instrument’s signal level and your playing style – lower
output levels and softer playing styles require a higher
setting of the Gain control than high output and “hard”
playing styles. Proper adjustment of this control will give
you clean sound with the lowest noise.
6: BASS CONTROL: Adjust the low frequency output of
the amp with this control: turn the control to the left for
less; to the right for more. This control allows a range of
±25dB at 40Hz.
7: MID CONTROL: Adjust the midrange frequency out-
put of the amp with this control: turn the control to the leftfor less; to the right for more. This control allows a range
of ±34dB at the selected frequency (see #8).
8: FREQUENCY:This control allows you to select one
of five midrange frequencies: 200, 400, 900, 1.5k or
2.5kHz. The setting of this control determines the effec-
tive range for the Mid control. 
9. TREBLE CONTROL: Adjust the high frequency out-
put of the amp with this control: turn the control to the left
for less; to the right for more. This control allows a range
of ±30dB at 4kHz.
10: MASTER:Set the overall output level of the amplifi-
er with this control. When the Post/Pre switch (#22) is at
the IN (“Post”) position, this control also affects the level
at the Balanced Line Out jack (#24).
11: HALF-POWER SWITCH:For situations where lower
playing volumes are appropriate, flip this switch to the
“60W” (down) position. This, in effect, bypasses one-half
of the output amplification devices, producing one-half
the output power as before. Of course, when full output
is desired, flipping the switch to the “100W” (up) position
returns the amplifier to its original 100 watt state.Note: In the 60 watt position the amplifier will deliver
approximately 40 watts into the internal speaker. To
deliver the full 60 watts into the internal 8 ohm speaker,
set the impedance switch (#18) to the 4 ohm setting.
Operation at either impedance setting is acceptable and
will yield some variances in the tonality of the unit.
Experiment with these settings to determine which
sound best suits your personal taste..
12: STANDBY SWITCH:Activate the amplifier with this
switch, afterthe Power switch has been turned on.
Always turn this switch off first, on last. Turn on the
Power switch (#13) at least 30 seconds before turn-
ing on the Standby switch.During breaks, turn the
Standby switch off, leaving the Power switch on. This
helps promote longer tube life.
13: POWER SWITCH: Turn on the main AC power with
this switch.Always turn this switch on first, off last.
Turn on the Standby switch (#12) at least 30 sec-
onds after turning on the Power switch.
17
MODEL:
SERIAL:
    LINE:         V ~          Hz
WATTS:             MAXB-15
B1500691242
120     60  
 
14
20212422
2315161819
14: AC LINE IN:Use the supplied power cord to connect
the amplifier to a suitable source of A.C. voltage. This is
a grounded, three-wire cord and must be connected to a
properly grounded outlet. DO NOT  attempt to defeat
the ground connection of the power cord!See the
serial number label for power ratings. 
15: FUSE: This protects the amplifier from damage to
overload conditions or power line surges. If the fuse
blows, replace it only with the same size and type.
16. BIAS SELECT:Allows for instant bias adjustment
when the TYPE of output tube is changed. The setting of
this switch mustmatch the type of tube being used! The
amplifier is shipped with 6L6 tubes installed.
17. SPEAKERS:Connect the amplifier to the internal
speaker and/or an extension speaker cabinet using these
jacks. Use heavy duty speaker cables terminated with
the proper connectors. The total speaker impedance can
not be less than 4 ohms. (Be sure to match the
Impedance Selector switch [#18] to the cabinet imped-
ance.) The B-15R’s cabinet impedance is rated at 8
ohms.
18. IMPEDANCE SELECTOR: Use this switch to match
the amplifier to the TOTAL impedance of your speaker
cabinet(s). Use the following chart to determine the total
impedance of parallel cabinets:CABINET NUMBER OF TOTAL
IMPEDANCE CABINETS IMPEDANCE
16 ohms 2 8 ohms
16 ohms 4 4 ohms
8 ohms 2 4 ohms
19: LINE OUT: Used with the Line In jack (#20), this may
serve as an effects loop: The signal from this jack would
go to the input of the effect. Alternate uses for this jack
include providing an unbalanced line level signal for con-
necting to an external amplifier or mixing console. The
signal at this jack is affected by the Master control (#10).
20: LINE IN:Used with the Line Out jack (#19), this may
serve as an effects loop: The signal from this jack would
come from the output of the effect. Alternate uses for this
jack include providing a means to tap directly into the
internal power amplifier, bypassing the input stages com-
pletely.
21. LINE OUT LEVEL:This controls the output level of
the signal at the Balanced Line Out jack (#24).
22: POST/PRE SWITCH:This switch determines
whether or not the signal at the Balanced Line Out jack
(#24) is affected by the settings of the tone and master
level controls. With the switch at the OUT (“Post”) pos-
tion, signal is affected; with the switch IN (“Pre”), the sig-
nal is not affected.23: LIFT/GND SWITCH:This switch lifts the ground of
the Balanced Line Out jack (#24) at the IN position.
Engage this switch only if there is excessive buzzing or
hum coming from the amplifier due to ground loops.
24: BALANCED LINE OUT: This jack provides a bal-
anced line level signal for connecting to a mixing console,
recording device or external amplifier.
25: HIGH FREQUENCY ATTENUATOR: This three
position rotary switch controls the output level of the inter-
nal high frequency driver. Use the tip of a flatblade screw-
driver to set this switch to the setting which best suits
your tastes.
26: FULL RANGE INPUTS: These are the input jacks for
the cabinet. Connect one of these jacks to the Speaker
ouput of the amplifier; the other jack may be used to carry
the amp signal to an extension cabinet if desired.
THE FRONT PANEL:
THE REAR PANEL:
2526
SERIAL #HIGH FREQUENCY
ATTENUATORFULL RANGE
INPUTSOFF 47-267-01
–6 0
POWER HANDLING: 150 WATTS
IMPEDANCE: 8 OHMS
MADE IN THE U.S.A. BY
SLM ELECTRONICS
1400 FERGUSON AVE.
ST. LOUIS, MO 63133 
B-15R 
						

							B-15R PORTAFLEX
TECHNICAL SPECIFICATIONS:
OUTPUT POWER RATING100 watts @ 5%THD, 8 ohm load, 120VAC 
SPEAKER SIZE AND RATINGAmpeg Vintage 15”, 8 ohm, 150 watt, 2” voice coil, 56 oz magnet 
High Efficiency Piezo Tweeter, 8 ohm, 150 watt (w/network)
CROSSOVER FREQUENCY3kHz 
ULTRA HIGH SWITCH6dB Boost @ 4kHz
ULTRA LOW SWITCH10dB Boost @ 40Hz
BASS CONTROL25dB Range @ 40Hz
MID CONTROL34dB Range @ 200, 400, 900, 1.5k or 2.5kHz
TREBLE CONTROL30dB Range @ 4kHz
INPUT IMPEDANCE0dB: 3M ohms; -15dB: 47k ohms
MAX. INPUT SIGNAL LEVEL ACCEPTED0dB: 1V RMS; -15dB: 5.75V RMS 
TOTAL SYSTEM GAIN50dB w/tones flat, Ultra Low and Ultra High off
SIGNAL TO NOISE RATIO90dB
POWER REQUIREMENTS120VAC, 60Hz, 400VA
100VAC, 50/60Hz, 400VA
230VAC, 50/60Hz, 400VA
DIMENSIONS 24”W x 16-1/2”D x 24-1/4”H w/amp flipped inside, w/out caster board
32-7/8” H w/amp flipped out, w/out caster board; 37-1/4” H w/caster board
WEIGHT:117 lbs
Ampeg continually develops new products, as well as improves existing ones. For this reason,
the specifications and information in this publication are subject to change without notice.
Ampeg is proudly Made in America.
©1998 SLM Electronics,
1400 Ferguson Avenue,
St. Louis, MO 63133 U.S.A.
P/N 47-667-03 • 04/98
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, NEVERremove or otherwise attempt to
defeat the ground pin of the power cord.
•Connect the amplifier ONLYto a properly ground-
ed 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 pre-
ceeding abuses, have it looked at by an autho-
rized service center.)
•NEVERset 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.
•Don’t 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 lev-
els are also capable of inflicting permanent hear-
ing loss or damage, if the exposure to such levels
is prolonged. Such damage is progressive and
irreversible! 
THIS EQUIPMENT HAS BEEN
DESIGNED AND  ENGINEERED
TO PROVIDE SAFE AND RELI-
ABLE OPERATION. IN ORDER
TO PROLONG THE LIFE OF THE
UNIT AND PREVENT ACCIDEN-
TAL DAMAGES OR INJURY,
PLEASE FOLLOW THESE PRE-
CAUTIONARY GUIDELINES:
CAUTION:TO REDUCE THE
RISK OF ELECTRIC SHOCK, DO
NOT OPEN CHASSIS; DO NOT
DEFEAT OR REMOVE THE
GROUND PIN OF THE POWER
CORD; CONNECT ONLY TO A
PROPERLY GROUNDED AC
POWER OUTLET.
WARNING:TO REDUCE THE
RISK OF FIRE OR ELECTRIC
SHOCK, DO NOT EXPOSE THIS
EQUIPMENT TO RAIN OR MOIS-
TURE.
CAUTION:NO USER-SERVICE-
ABLE PARTS INSIDE. REFER
SERVICING TO QUALIFIED SER-
VICE PERSONNEL.
CAUTION:OUR AMPLIFIERS
ARE CAPABLE OF PRODUCING
HIGH SOUND PRESSURE LEV-
ELS. CONTINUED EXPOSURE
TO HIGH SOUND PRESSURE
LEVELS CAN CAUSE PERMA-
NENT HEARING IMPAIRMENT
OR LOSS. USER CAUTION IS
ADVISED AND EAR PROTEC-
TION IS RECOMMENDED IF
UNIT IS OPERATED AT HIGH
VOLUME.CAUTIONRISK OF ELECTRIC SHOCK
DO NOT OPEN
CAUTION: TO REDUCE THE RISK OF ELECTRIC SHOCK,
DO NOT REMOVE COVER.
NO USER-SERVICEABLE PARTS INSIDE.
REFER SERVICING TO QUALIFIED SERVICE PERSONNEL.
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 DUTILISATION
UNBEDINGT IN DER BEDIENUNGSANLEITUNG NACHSCHLAGENEXPLANATION OF GRAPHICAL SYMBOLS:
EXPLICACION DE SIMBOLOS GRAFICOS:
EXPLICATION DES SYMBÔLES GRAPHIQUES:DANGEROUS VOLTAGE
“VOLTAJE PELIGROSO”
DANGER HAUTE TENSION
GEFAHLICHE SPANNUNG==
PRECAUCIONRIESGO DE CORRIENTAZO
NO ABRA
PRECAUCION 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
ATTENTIONRISQUE DELECTROCUTION
NE PAS OUVRIR
ATTENTION: POUR REDUIRE DELECTROCUTION NE PAS
ENLEVER LE COUVERCLE. AUCUNE PIECE INTERNE NEST REPRABLE
PAR LUTILISATEUR. POUR TOUTE REPARATION, SADRESSER A UN
TECHNICIEN QUALIFIE.
VORSICHTELEKTRISCHE SCHLAGGEFAHR
NICHT OFFENEN
VORSICHT: ZUR MINIMIERUNG ELEKTRISCHER SCHLAGGEFAHR NICHT
DEN DECKEL ABENHMEN. INTERNE TEILE KONNEN NICHT VOM
BENUTZER GEWARTET WERDEN. DIE WARTUNG IS QUALIFIZIERTEM
WARTUNGSPERSONAL ZU UBERLASSEN.
ESTE APARATO HA SIDO DISE-
NADO Y CONSTRUIDO PARA
PROVEER ANOS DE OPERA-
CION SEGURA Y CONFIABLE.
PARA PROLONGAR LA VIDA DE
ESTA UNIDAD E IMPEDIR
DANOS ACCIDENTALES  POR
FAVOR SIGA ESTAS INSTRUC-
CIONES PREVENTIVAS:
PRECAUCION:PARA DISMINUIR
EL RIESGO DE DESCARGAS
ELECTRICAS: (1) NO ABRA LA
CUBIERTA, (2) NO ES
RECOMENDABLE REMOVER O
DESACTIVAR LA PATA DEL
POLO A TIERRA DEL CABLE  DE
CORRIENTE, CONECTE COR-
RECTAMENTE A UNA TOMA DE
CORRIENTE A TIERRA.
ADVERTENCIA:PARA EVITAR
DESCARGAS EL ECTRICAS O
PELIGRO DE INCENDIO, NO
DEJE ESTE APARATO
EXPUESTO A LA LLUVIA O
HUMEDAD.
PRECAUCION: NO HAY PIEZAS
ADENTRO QUE EL USUARIO
PUEDE REPARAR. DEJE TODO
MANTENIMIENTO A LOS TÉCNI-
COS CALIFICADOS.
PRECAUCION:NUESTROS
AMPLIFICADORES PUEDEN
PRODUCIR NIVELES DE PRE-
SION DE SONIDO ALTO.
EXPOSICION CONTINUADA A
LOS NIVELES DE PRESION DE
SONIDO ALTO PUEDE CAUSA
DANO PERMANENTE A SU
OIDO. ES ACONSEJADO QUE
USE PRECAUCION AL USUARIO
Y ES RECOMENDADO PROTEC-
CION PARA LOS OIDOS SI LA
UNIDAD ES OPERADA A VOLU-
MEN ALTO.CET ÉQUIPEMENT AVAIT ÉTÉ
INVENTÉ ET ARRANGÉ POUR
POURVOIR DES ANNÉES
DUSAGE SAUF ET SÛR.  POUR
PROLONGER LA VIE DE CET
APPAREIL ET POUR EMPÊCHER
LES DOMMAGES ET LES TORTS
ACCIDENTELS, SUIVEZ LES
INSTRUCTIONS DE PRÉCAU-
TION.
AVERTISSEMENT:POUR
RÉDUIRE LES RISQUES DÉLEC-
TROCUTION: (1)  N’OUVREZ
PAS LE CHÂSSIS, (2)  NE PAS
ESSAYER DE SUPPRIMER LA
BROCHE CORRESPONDANT À
LA TERRE.
ATTENTION: POUR RÉDUIRE
LES RISQUES DUN FEU OU
DÉLECTROCUTION, N’EX-
POSEZ PAS LAPPAREIL À LA
PLUIE OU À LA MOITEUR.
ATTENTION:IL NY A PAS
D’ÉLÉMENTS RÉPARABLES
DANS LAPPAREIL.  CONSULTER
UN TECHNICIEN QUALIFIÉ
POUR LES RÉPARATIONS.
ATTENTION:NOS AMPLIFICA-
TEURS SONT CAPABLES DE LA
PRODUCTION DES NIVEAUX DE
SON DUNE HAUTE PRESSION.
LEXPOSITION CONTINUE AUX
CES NIVEAUX PEUT CAUSER
LA SURDITÉ PERMANENTE.  LA
PRUDENCE EST ADVISÉ À UTIL-
ISATEUR ET LA PROTECTION
DES OREILLES EST RECOM-
MANDÉ SI LAPPAREIL EST
UTILISÉ À UN HAUT NIVEAU DE
VOLUME.
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