Ampeg B3158 Musical Instrument Amplifier User Manual

Owner’s Guide
for the
B3 / B328 / B3158
Bass Amplifier
Made in the U.S.A. by
B3/B328/B3158 Bass Amplifier
TABLE OF CONTENTS
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
Important Safeguards and Precautions . . . . . . . . . .2
The Front Panel Controls and Their Use . . . . . . .3,4
The Rear Panel . . . . . . . . . . . . . . . . . . . . . . . . . .4,5
Some Suggested Settings . . . . . . . . . . . . . . . . . . .6
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . .7
System Block Diagram . . . . . . . . . . . . . . . . . . . . . .7
Technical Specifications . . . . . . . . . . . . .back cover
Features
In the world of high performance bass amps, Ampeg amplifiers
stand alone. In true Ampeg tradition, your new B3/B328/B3158
offers you more power, performance and flexibility than any other
bass amplifier in its class. The outstanding features of your new
amplifier, features which set it apart from the competition, are listed below:
• 9-BAND GRAPHIC EQ: Use as a “second channel” for bass
solos, or to shape the sound to your own exacting standards. An
independent level control lets you adjust the Graphic EQ volume
An Introduction to your new Ampeg
Bass Amplifier
• BALANCED LINE OUTPUTS: Independent level control. XLR
type jack to patch into house consoles, mixing boards, or external
power amplifiers
Thank you for making one of the best choices you will
ever make for your musical career – choosing one of the
finest bass amps available, an Ampeg B3/B328/B3158.
Your new bass amplifier offers many outstanding features.
One hundred fifty watts of pure bass energy, total tone control, and rugged construction make each a true performer’s
bass amp.
• EFFECTS LOOP: Connect your effects here for increased intensity and quieter operation
• DRIVE CONTROL: To add harmonics for tube-like overdrive
• BALANCE CONTROL (B3158 only): To fine tune the mix
between the Biamp High and Biamp Low outputs
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.
• Whenever using tall or stacked speaker cabinets, use them ONLY on a level surface. NEVER set tall or stacked cabinets on a surface
with more than a five degree incline since tipping or falling could occur, possibly causing serious injuries.
• 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 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!
CAUTION
ATTENTION
VORSICHT
RISK OF ELECTRIC SHOCK
DO NOT OPEN
RISQUE D'ELECTROCUTION
NE PAS OUVRIR
ELEKTRISCHE SCHLAGGEFAHR
NICHT OFFENEN
CAUTION: TO REDUCE THE RISK OF ELECTRIC SHOCK,
DO NOT REMOVE COVER.
NO USER-SERVICEABLE PARTS INSIDE.
REFER SERVICING TO QUALIFIED SERVICE PERSONNEL.
ATTENTION: 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.
VORSICHT: ZUR MINIMIERUNG ELEKTRISCHER SCHLAGGEFAHR NICHT
DEN DECKEL ABENHMEN. INTERNE TEILE KONNEN NICHT VOM
BENUTZER GEWARTET WERDEN. DIE WARTUNG IS QUALIFIZIERTEM
WARTUNGSPERSONAL ZU UBERLASSEN.
THIS EQUIPMENT HAS BEEN DESIGNED AND ENGINEERED TO PROVIDE SAFE AND RELIABLE OPERATION. IN ORDER TO PROLONG THE LIFE OF THE UNIT AND PREVENT ACCIDENTAL DAMAGES OR INJURY, PLEASE FOLLOW THESE PRECAUTIONARY GUIDELINES:
WARNING: 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.
CAUTION: TO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK, DO NOT EXPOSE THIS EQUIPMENT TO RAIN OR MOISTURE.
CAUTION: NO USER-SERVICEABLE PARTS INSIDE. REFER SERVICING TO QUALIFIED SERVICE PERSONNEL.
CAUTION: OUR AMPLIFIERS ARE CAPABLE OF PRODUCING HIGH SOUND PRESSURE LEVELS. CONTINUED EXPOSURE TO HIGH SOUND PRESSURE LEVELS CAN CAUSE PERMANENT
HEARING IMPAIRMENT OR LOSS. USER CAUTION IS ADVISED AND EAR PROTECTION IS RECOMMENDED IF UNIT IS OPERATED AT HIGH VOLUME. The chart below shows the U.S.
Government Occupational Safety and Health Administration (OSHA) regulations which were in effect at the time of this publication for permissible noise exposure, per 29CRF1910, Table G-16.
SOUND LEVEL dBA
SLOW RESPONSE
DURATION PER DAY
IN HOURS
SOUND LEVEL dBA
SLOW RESPONSE
DURATION PER DAY
IN HOURS
90
92
95
97
100
8
6
4
3
2
102
105
110
115
1-1/2
1
1/2
1/4 or less
According to OSHA, any exposure in excess of those listed above could result in some hearing loss.
2
EXPLANATION OF
GRAPHICAL SYMBOLS:
"DANGEROUS VOLTAGE"
= "DANGER HAUTE TENSION"
"GEFAHLICHE SPANNUNG"
"IT IS NECESSARY FOR THE USER TO REFER TO THE INSTRUCTION MANUAL"
= "REFERREZ-VOUS AU MANUAL D'UTILISATION"
"UNBEDINGT IN DER BEDIENUNGSANLEITUNG NACHSCHLAGEN"
B3/B328/B3158 Bass Amplifier
The Front Panel Controls and Their Use
INPUT
GAIN
DRIVE
BASS
ULTRA MID
TREBLE
EQ
ON
40Hz
80Hz
150Hz
300Hz
600Hz
900Hz
2kHz
5kHz
8kHz
+12dB
MASTER
BALANCE
FLAT
0
-15dB
PAD
LIMIT
PEAK
-12dB
1
2
3
4
5
6
7
1. INPUT: The signal output from an instrument (active or passive) or a line level signal
may be connected here by means of a shielded instrument cable.
2. -15dB PAD: This switch, when depressed,
attenuates the input signal by 15dB.
Attenuation allows the Gain control (#4) to be
used in a more usable (higher) position. If
clipping is indicated with the Gain control at a
low setting, attenuation is needed.
8
9
10
LO
11
ed clockwise, signal level is increased to
drive the preamp harder (into distortion). The
tone of the signal is also changed to provide
a smoother overdrive. (The tone controls may
have to be readjusted to obtain the overall
desired tone.) The Gain control (#4) and 15dB Pad (#2) interact with the Drive control.
For greater overdrive, the Pad switch should
be out and the Drive control fully clockwise.
Use the Gain control to set the amount of
overdrive desired. The Peak LED (#3) will illuminate steadily when the amp is used in this
manner.
3. PEAK LED: This LED flashes when the
signal level into the preamp approaches clipping. Adjust the Gain control (#4) until a
strong signal from your instrument causes 6. BASS: This is the primary low frequency
control which allows for 12dB of cut or boost
this LED to flicker.
at 50Hz.
NOTE: If the LED flashes frequently with the
Gain at a low setting, use the -15dB pad (#2) 7. ULTRA MID: This is the primary midrange
to attenuate the input signal and readjust the control. Rotate this control to the left of center
for a “contoured” sound (more distant, less
Gain.
midrange output) or to the right of center for a
4. GAIN: This serves as the input level conpronounced (more up-front) tone.
trol for the amplifier. For the best signal to
noise ratio set this control so the Peak LED 8. TREBLE: This is the primary high frequen(#3) flashes when you strike a string fairly cy control which allows for 22dB of cut or
17dB of boost at 5kHz.
hard.
5. DRIVE: This control is used to overdrive
the preamp in order to get various harmonic
enhancement or distorted sounds. In the fully
counterclockwise position the preamp is in
the cleanest condition. As the control is rotat-
1. ENTRADA: Conecte aquí su guitarra de bajos
usando un cable blindado para instrumentos.
2. TERMINAL DE -15dB: Si su bajo tiene captadores de alta salida ó circuitos electrónicos activos,
usted tal vez notará que el díodo (LED) de Picos
(#3) parpadea ó permanece iluminado aún en posiciones bajas del control de Ganancia (#4). Conecte
esta Terminal para conservar limpia la señal. Esto
atenuará la señal de entrada hacia el preamplificador, lo que le permitirá obtener la mejor relación
de señal-a-ruido para su bajo.
3. DIODO (LED) DE PICOS: Este LED se iluminará cuando cualquier etapa de preamplificación se
encuentre cerca del punto de sobreimpulso. Ajuste
el control de Ganancia (#4) hasta que una señal
fuerte de su bajo cause un parpadeo de este LED.
ON
HI
PULL
EQ ON
LOW HIGH
12
13
14
15
10. GRAPHIC EQ: These sliders control the
output frequencies indicated above each control. The center position of each control is flat
(no boost or cut).
11. MASTER: Set the overall output level of
the amplifier with this control. Pulling this
knob out actives the Graphic EQ (#10). When
a footswitch is connected (#24, rear panel)
this switch is disabled.
12. BALANCE (B3158 only): This control
proportions the output signal between the low
and high frequency output jacks (see #18,
rear panel) when using the amp in the biamp
mode.
13. LIMIT LED(S): The LED illuminates
whenever the amplifier is near full output,
indicating that the internal limiter is keeping
the output from distorting.
NOTE: There are two Limit LEDs only on the
B3158: one for its low frequency power amp
and one for its high frequency power amp.
14. POWER ON LED: This LED indicator illuminates when the POWER switch (#15) is ON.
15. POWER SWITCH: This heavy-duty rock9. EQ ON LED: This LED illuminates when
er switch applies the power to the amplifier.
the EQ is turned on by either the Master
The amp is ON when the top of the switch is
Control (#11) or a footswitch (#24, rear
depressed, OFF when the bottom of the
panel).
switch is depressed.
NOTA: Si el LED permanece iluminado aún con la
Ganancia en una posición baja, utilice la Terminal
de -15dB (#2) para atenuar la señal de entrada y
reajuste la Ganancia.
4. GANANCIA: Esto sirve como el control de
nivel de entrada para el amplificador. Para lograr la
mejor relación de señal-a-ruido fije este control para
que el LED de Picos (#3) parpadee cuando usted
pulse con fuerza alguna cuerda.
5. IMPULSO: Este control se usa para sobreimpulsar el preamplificador a fin de conseguir varios
realces armónicos ó sonidos de distorsión. En la
posición totalmente contraria a las manecillas del
reloj, el preamplificador se encontrará en la posición
más “limpia”. Conforme el control se gire a favor de
las mane-cillas del reloj, el nivel de la señal se incre-
mentará para impulsar el preamplificador con
mayor fuerza (hacia la distorsión). El tono de la
señal también cambia para proveer un sobreimpulso más suave. Tal vez tengan que ajustarse los
controles de tono para obtener el tono general
deseado. El control de Ganancia (#4) y la Terminal
de -15dB (#2) interaccionan con el control de
Impulso. Para un sobreimpulso mayor, el interruptor
de la Terminal debe estar apagado y el control de
Impulso totalmente a favor de las manecillas del
reloj. Use el control de Ganancia para fijar la cantidad deseada de sobreimpulso. El díodo LED de
Picos (#3) se iluminará en forma constante cuando
el amplificadora se utilice de esta manera.
6. BAJOS: Esta perilla sirve como el control primordial para las frecuencias bajas. Esto permite un
rango de 8dB de recorte ó de refuerzo a 50Hz.
3
B3/B328/B3158 Bass Amplifier
The Front Panel Controls and Their Use
7. ULTRA-MEDIANOS: Este es el control primordial para el rango de las frecuencias medianas. Gire
el control del centro hacia la izquierda para lograr
un sonido de contorno (más distante, menor salida
en el rango mediano) ó del centro hacia la derecha
para obtener un sonido realmente penetrante.
8. AGUDOS: Esta perilla sirve como el control primordial para las frecuencias altas. Esto permite un
rango de 17dB de refuerzo ó 22dB de recorte a
5kHz.
9. EQ EN LED: Este dÌodo LED indicador se ilumina cuando usted activa el EQ mediante el control
Maestro (#14) del panel delantero ó el interruptor de
pie (#24) del panel posterior.
10. EQ GRAFICO: Estos controles deslizantes
(cursores) le permiten ajustar la salida de las frecuencias que se muestran junto a cada control. La
posición central de cada control es plana (sin
refuerzo ni recorte). Estos controles sólo afectan el
sonido cuando el EQ esé prendido.
11. MAESTRO: Fije mediante este control el nivel
general de salida del amplificador. El Circuito de
Efectos y la Salida Equilibrada (#19, 20, 23) no se
verán afectadas por el control Maestro. Jalando el
control Maestro se prende el EQ Gráfico (#10).
Cuando se utiliza el interruptor de pie, se pasa por
alto el interruptor del panel delantero.
12. EQUILIBRIO (SOLO EN EL B358): Este control varía el nivel de la señal entre las salidas de
bajas y altas frecuencias (véase el #18) para adecuar aún más el sonido).
13. DIODOS LED DE LIMITE: Este LED indicador
parpadeará cada vez que se requiera el circuito limitador interno para conservar limpia la señal de salida del amplificador. Esto indica que el amplificador
está aproximándose a su salida máxima y que el
limitador está impidiendo el aplanamiento (“clipping”) de la señal de salida.
NOTA: Hay dos circuitos Limitadores dentro del
B3158: uno para su amplificador de potencia de
frecuencias bajas y otro para su amplificador de
potencia de frecuencias altas. Todos los demás
modelos tienen un solo circuito Limitador, y por lo
tanto un solo LED de Limite.
14. DIODO LED DE POTENCIA ENCENDIDA:
Este LED indicador se ilumina cuando se prende el
interruptor de Potencia (#15).
15. INTERRUPTOR DE POTENCIA: Este interruptor de servicio pesado tipo vaivén aplica la energía
de CA al amplificador: el amplificador se PRENDE
en la posición hacia arriba (“I”), y se APAGA en la
posición hacia abajo
The Rear Panel
CAUTION
MODEL
B-3158
RISK OF ELECTRIC SHOCK
DO NOT OPEN
DE CHOC ELECTRIQUE
AVIS: RISQUE
NE PAS OUVRIR
WARNING:
FOR 100-120VAC, 50/60Hz:
FOR 220-240VAC, 50/60Hz:
T5A, 250V
T2.5A, 250V
TO REDUCE THE RISK OF FIRE OR
ELECTRIC SHOCK, SO NO EXPOSE THIS EQUIPMENT TO RAIN OR MOISTURE.
SPEAKERS
SERIAL #
500 WATTS MAX.
115VAC-60Hz
EFFECTS
LOOP
POST
PRE
-20dB
0dB
HIGH
50 WATTS
@8 OHMS
8 OHM MIN.
16
17
16. FUSE: This protects the unit from damage due to overload conditions or power
line surges. In case of failure, replace it only
with the same size and type.
17. AC LINE IN: Firmly insert the supplied
AC power cord into this socket until it is fully
seated. Plug the male end of the cord into a
grounded AC outlet. DO NOT DEFEAT
THE GROUND PRONG OF THE AC
PLUG!
18. SPEAKER OUTPUT(S): This section is
different for each of the three models. The
B3158 is shown in the illustration above.
The B3158 has two internal amplifiers,
one for the high frequencies, one for the
low. Each amplifier section has its own
speaker output jack, factory-wired to the
internal speakers. To use external speaker
cabinets, unplug the connectors from the
jacks and use speaker cables with 1/4”
plugs to connect the LOW jack to your low
frequency cabinet and the HIGH jack to the
high frequency cabinet. Use the Balance
control (#12, front panel) to proportion the
4
LOW
100 WATTS
@4 OHMS
4 OHM MIN.
18
output signal between the low and high frequency output jacks. Observe the minimum
impedance ratings for each output (8 ohms
for high, 4 ohms for low).
The B3 has a single speaker output jack
(wired at the factory to its speaker enclosure). To use an external speaker cabinet,
disconnect the amplifier from the enclosure
and connect it to the external cabinet, using
a speaker cable with 1/4” plugs. Observe
the 4 ohm minimum impedance rating.
The B328 has a single speaker output
jack, and two input jacks on its speaker cabinet: WITH TWEETER and WITHOUT
TWEETER. Connect the speaker cable to
the jack which gives you the best sound. To
use an external speaker cabinet, disconnect the amplifier from the enclosure and
connect it to the external cabinet, using a
speaker cable with 1/4” plugs. Observe the
4 ohm minimum impedance rating.
RETURN
19
SEND
20 21 22
BAL.
OUT
FOOT
SWITCH
23
24
The following chart shows the total
impedance load when connecting speaker
cabinets in parallel:
Cabinet
Impedance
# of
Cabs
Total
Impedance
8Ω
16Ω
16Ω
2
2
4
4Ω
8Ω
4Ω
19. EFFECTS RETURN: To use an external
effects device or other signal processor,
connect the OUTPUT of the device to this
jack using a shielded cable. This returns the
processed signal into the amplifier’s master
section.
20. EFFECTS SEND: Connect the output
from this jack to the INPUT of an external
effects device using a shielded cable. This
sends a post-EQ signal to your effects.
Since plugging a cable in here does not
break the through connection to the power
amp, this jack can also be used as an
unbalanced line out jack.
B3/B328/B3158 Bass Amplifier
The Rear Panel
21. PRE/POST SWITCH: You can select
either pre or post-EQ for the signal at the
Balanced Out jack (#23) with this switch.
With the switch in the OUT position, the signal at the jacks will be pre-EQ. This is a
direct output which is not affected by any
EQ or boost settings. With the switch
depressed, the signal is post-EQ and is
controlled and modified by the tone controls, Graphic EQ and Effects Loop.
22. -20dB SWITCH: This switch adjusts the
output level at the Balanced Out jack (#23).
The switch works independently from the
front panel Master control. Depressing the
switch activates the -20dB pad, which
allows patching into a mixer’s mic input
without overdriving it.
23. BALANCED OUT: This XLR-type connection supplies a balanced preamp output
signal for connecting to a house mixing
board, recording console or external amplifiers with balanced inputs. The signal can be
set to pre or post-EQ by the Pre/Post switch
(#21). The level can be adjusted for either
mic or line type inputs using the -20dB
switch (#22).
24. FOOTSWITCH: This jack accepts the
1/4” plug from a 1-button footswitch, allowing remote control of the Graphic EQ on/off
function. When a footswitch is used, the
front panel Master Pull EQ On switch (#11)
is bypassed.
16. FUSIBLE: Esto protege a la unidad contra daños debidos a condiciones de sobrecarga ó sobretensiones transitorias en la línea de
energía. Si el fusible se quema, repóngalo
sólo con el mismo tipo y tamaño.
17. ENTRADA DE LA LINEA DE CA:
Conecte firmemente a este receptáculo el
cable suministrado de corriente de CA, oprimiéndolo hasta que quede totalmente asentado. Enchufe el extremo macho del cordón a
una salida aterrizada de CA. ¡NO PASE POR
ALTO EL BORNE DE TIERRA DE LA CLAVIJA DE CA!
18. SALIDA(S) DE LA(S) BOCINA(S): Esta
sección es diferente para cada de los tres
modelos. El B3158 aparece en la ilustración
arriba.
El B3158 tiene dos amplificadores internos, uno para las frecuencias agudas, uno
para las graves. Cada sección de amplificadores tiene su propio “jack” de salida para
bocinas. Este modelo viene cableado desde
la fábrica a su propio gabinete de bocinas: el
conector negro “cola de cochino” va al “jack”
BAJO, el gris al “jack” AGUDO. Para utilizar
gabinetes de bocinas externos, desenchufe
los conectores de los “jacks” y use cables
para bocinas con clavijas de 1/4” para conectar el “jack” BAJO a su gabinete de frecuencias bajas y el “jack” de AGUDOS al gabinete
de frecuencias altas. Observe la especificación de impedancias mínimas para cada
“jack” (8 ohms para los agudos, 4 ohms para
los bajos).
El B3 tiene un ‘jack” de salida para una
sola bocina (que viene cableado desde la
fábrica a su propio gabinete de bocinas). Para
usar un gabinete externo de bocinas, desenchufe el amplificador del gabinete y con-
nectarlo a el gabinete externo. Use un cable
para bocinas con clavijas de 1/4”. Observe la
especificación de 4 ohms de impedancia
como mínimo.
El B328 tiene un ‘jack” de salida para
bocinas, y dos “jacks” de entrada en el gabinete de los bocinas internal: “WITH TWEETER” (con la bocina de las agudos) y “WITHOUT TWEETER” (sin la bocina de las agudos). Para usar un gabinete externo de bocinas, desenchufe el amplificador del gabinete
y connectarlo a el gabinete externo. Use un
cable para bocinas con clavijas de 1/4”.
Observe la especificación de 4 ohms de
impedancia como mínimo.
La tabla a continuación muestra la carga
de impedancia total cuando se conecten gabinetes de bocinas en paralelo:
21. INTERRUPTOR PRE/POST: Usted
puede seleccionar por medio de este interruptor ya sea pre ó post-EQ para la señal en
el “jack” de Salida Equilibrada (#23). Con el
interruptor en la posición de FUERA, la señal
en los “jacks” será pre-EQ. Esta es una salida
directa no afectada por ningunas posiciones
del EQ ó de refuerzo. Con el interruptor hacia
adentro, la señal es post-EQ y se controla y
modifica mediante los controles de tono, el
EQ Gráfico y el Circuito de Efectos.
22. INTERRUPTOR DE -20dB: Este interruptor ajusta el nivel de salida en el “jack” de
Salida Equilibrada (#23). El interruptor funciona independientemente del control
Maestro del panel delantero. Al oprimirse el
interruptor hacia adentro se activa la terminal
de los -20dB, lo que permite conectarse a las
entradas para micrófonos en un mezclador
sin sobreimpulsarlos.
23. SALIDA EQUILIBRADA: Esta conexión
tipo XLR proporciona una señal de salida
equilibrada de preamplificación para conectarse a un tablero mezclador local, una consola grabadora ó amplificadores externos
con entradas equilibradas. La señal se puede
establecer como pre ó post-EQ mediante el
interruptor Pre / Post (#21). El nivel se puede
ajustar para entradas de tipos ya sean de
micrófono ó de línea utilizando el interruptor
de -20dB (#22).
24. INTERRUPTOR DE PIE: Este “jack”
acepta la clavija de 1/4” de un interruptor de
pie de un solo botón, lo que permite un control remoto de la función de prender / apagar
del EQ Gráfico. Cuando se utiliza un interruptor de pie, se pasa por alto el interruptor
Maestro para Prender ó Jalar el EQ (#11).
Impedancia de
cada Gabinete
# de
Gabinetes
Impedancia
Total
8 ohms
16 ohms
16 ohms
2
2
4
4 ohms
8 ohms
4 ohms
19. RETORNO DE EFECTOS: Para utilizar
un dispositivo de efectos externo ú otro procesador de señales, conecte la SALIDA del dispositivo a este “jack” usando un cable blindado. Esto alimenta la señal procesada a la sección maestra del amplificador.
20. ENVIO DE EFECTOS: Conecte la salida
de este “jack” a la ENTRADA de un dispositivo de efectos externo usando un cable blindado. Esto envía una señal post-EQ a sus efectos. Siendo que la conexión de un cable en
este lugar no rompe la conexión directa al
amplificador de potencia, esto se puede utilizar como otra linea hacia afuera.
5
B3/B328/B3158 Bass Amplifier
Some Suggested Settings*
ROCK:
GAIN
DRIVE
BASS
ULTRA MID
TREBLE
The setting of the
Gain control
depends on your
particular instrument.
JAZZ:
GAIN
DRIVE
BASS
ULTRA MID
TREBLE
COUNTRY:
GAIN
DRIVE
BASS
ULTRA MID
TREBLE
DRIVE
BASS
ULTRA MID
TREBLE
FUNK “POPPING:”
GAIN
6
The Master control
should be set to produce the appropriate
output volume level.
The Graphic EQ can
be used to tailor the
amplifier to your
speaker cabinets, to
compensate for
room acoustics and
to “fine tune” your
sound.
B3/B328/B3158 Bass Amplifier
Troubleshooting
In the unlikely event that your B3/B328/B3158 should malfunction, take a few minutes to troubleshoot it before you call
for service. You can save yourself time and money by doing it yourself, and often the cure for the problem is something
quite simple.
NO SOUND
NO SOUND
LEDs LIGHT
LEDs DON’T LIGHT
Check amp controls, check
for signal from instrument
Check AC outlet
POOR SOUND
OUTLET OK
NO SOUND
Check instrument, cables
SOUND OK
Check power cord,
fuse, power switch
Listen for hum
NO HUM
HUM
Check speaker
Unplug instrument,
touch tip of cable
SOUND OK
NO POWER
Check speaker(s)
Check house fusebox
or circuit breaker
SPEAKER(S) OK,
POOR SOUND
OK
SPEAKER(S)
DEFECTIVE
Replace speaker(s)
SPEAKER OK
NO CHANGE
LOUD HUM
Replace cable
Check bass pickup
NO CHANGE
SOUND OK
POOR SOUND
SOUND OK
SOUND OK
SEE BELOW
SEE BELOW
If the problem isn’t covered above, or if the steps lead you here, then contact your Ampeg dealer for service information. Also, you should refer your amp for servicing if it gets dropped, has liquid spilled into it, or sustains damage to its
power cord (see page 2).
System Block Diagram
PEAK LED
LIMIT LED
TONES
INPUT
B3, B328
9 BAND EQ
POWER
AMP
SPEAKER
OUT
-15dB
PAD
GAIN
DRIVE
FOOT
SWITCH
EQ ON
BASS
TREBLE
ULTRA MID
B3158
MASTER
BIAMP
X-OVER
EFFECTS
SEND
EFFECTS
RETURN
POST
2
PRE
-20dB
3
BALANCED
OUT
BALANCE
LOW LIMIT LED
LOW
FREQ
LOW
POWER
SPEAKER
AMP
OUT
HIGH LIMIT LED
HIGH
FREQ
HIGH
POWER
SPEAKER
AMP
OUT
7
B3/B328/B3158 Bass Amplifier
Technical Specifications
OUTPUT POWER RATING
B3, B328: 150 Watts RMS, 4Ω load
B3158: Low Freq - 100 Watts RMS, 4Ω load
High Freq - 50 Watts RMS, 8Ω load
POWER REQUIREMENTS
120VAC, 60Hz, 170VA
100/115VAC, 50/60Hz, 170VA
220-240VAC, 50/60Hz, 170VA
TONE CONTROL RANGE
Bass: ±8dB @ 50Hz
Ultra-Mid: +5, -17dB @500HZ
Treble: +17, -22dB @ 5KHZ
GRAPHIC EQ RANGE
±11dB @ 40Hz; ±8dB @ 80, 150, 300, 600, 900, 2kHz; ±9dB @ 9kHz
GAIN
66dB typical, tones @ center
SIGNAL TO NOISE RATIO
75dB typical
INTERNAL SPEAKERS
B3
B328
B3158
Low Frequency:
Size/Type: 15” Ampeg Custom (1) 8” Polypropylene (2)
15” Ampeg Custom (1)
Magnet: 56 oz
30 oz
56 oz
Voice Coil: 2.5”
1.5”
2.5”
Impedance: 4Ω
8Ω
4Ω
High Frequency:
Size/Type: N/A
Hi-Efficiency Piezo (1)
8” Polypropylene (1)
Magnet:
30 oz
Voice Coil:
1”
Impedance:
8Ω
SIZE AND WEIGHT
B3
B328
B3158
(W x H x D)
20”x26”x13.5”
20”x18.75”x13.5”
20”x34.5”x14.5”
68 lbs.
57 lbs.
84 lbs.
www.ampeg.com
Ampeg reserves the right to change specifications without notice.
Ampeg is proudly Made in America. ©1999 SLM Electronics, 1400 Ferguson Avenue, St. Louis, MO 63133 U.S.A.
P/N 47-588-03 • 10/99