12. EFFECT LOOP SEND/RETURN JACKS
The EFFFECT LOOP - SEND and RETURN jacks are used to connect external effects into the
signal chain. The loop is inserted after the DRIVE and TONE CONTROLS but before the VOLUME
control. To use the effects loop, connect the SEND jack to the input of the effects unit and con-
nect the RETURN jack to the output of the effects unit. The effects loop can be turned on with
the EFFECT LOOP switch on the front panel or by using the optional FS22 footswitch. When
the front panel switch is in the UP position, the loop is engaged regardless of the footswitch.
The status of the effects loop is indicated on the front panel by the BLUE LED “on” next to the
EFFECT LOOP switch.
13. DIRECT OUT XLR
The DIRECT OUT XLR is a balanced output that can be configured in a number of different
ways. The PRE / POST switch is used to select a pre or post preamp feed. In the “PRE” (OUT)
position, a direct feed is taken off of the INPUT jack and is similar to using a direct input box
at the bass guitar output. In the “POST” (IN) position, the feed is post the preamp section and
contains all of the signal that is sent to the power amp and speakers. To set the output, use the
DIRECT OUT LEVEL control. A GND/LIFT switch is also available for the DIRECT OUT XLR jack.
Set this switch for the lowest noise when using this output. When the GND/LIFT switch is
depressed, the signal ground is lifted from this jack thus eliminating any ground loops between
the direct out and the gear it is feeding.
14. FOOTSWITCH
Connect the optional FS22 footswitch to remotely control the MUTE function and the EFFECTS
LOOP bypass. The first button on the FS22 turns the MUTE on and off and the second button
turns the EFFECTS LOOP on and off. Any standard footswitch with a stereo plug will work.
15. TUNER LINE OUT JACK (UNMUTED)
The TUNER LINE OUT jack is provided as a place to hook up a tuner. This output is unaffected
by the MUTE function so that you may tune your bass quietly.
16. SPEAKER OUTPUTS
The B2000 contains two 1/4”/SPEAKON
®
combo speaker output connectors. Multiple speak-
ers can be attached to either the 1/4” or SPEAKON
®
jacks so long as the total impedance is not
below 2Ω. See SPEAKER COMBINATIONS AND OHMS chart.
17. TUBE BYPASS
The preamp 12AX7 Tube can be routed in or out of the preamp circuit using the bypass switch.
Set the switch IN to send your bass signal through the tube. Set the switch in the OUT posi-
tion to bypass the tube.
FOR MAXIMUM OUTPUT:
A. To get more output, use multiple speakers or enclosures. Every time you double your
speakers, your acoustic output goes up by a factor of four. Load the amplifier down to
its lowest minimum impedance for maximum RMS power.
B. To get the highest output from your B2000 bass amp use two 4 ohm speakers. Plug
two SPEAKON
®
cables into the rear SPEAKER OUTPUT connectors or daisy-chain another
SPEAKON
®
from speaker to speaker. Two 4 ohm speakers will give you a total imped-
ance of 2 ohms, which is the maximum power from your amp. If you use more than
two 4 ohm speakers, your amp will shut off and go into the “protect” mode. To reset,
turn your amp off and connect only two 4 ohm speakers.
C. SPEAKON
®
cables are recommended for your bass rig because of their high current
capacity. While standard 1/4” speaker cables will work, the CARVIN 12 GA SPEAKON
®
cables will allow higher currents to pass through the cable to extract every watt from
your amp.
HELPFUL HINTS
1) NO SOUND FROM AMP: The MUTE function has been inadvertently engaged, speakers
have been improperly connected or Effect Loop has been improperly connected.
2) NO HIGH FREQUENCIES: Tweeters or midrange drivers have been damaged from too
much power.
3) WEAK BASS: The speaker systems are wired out of phase to each other. To correct,
reverse the wires on one of the speaker connectors.
4) DIR XLR HUM: Try switching the rear GND LIFT switch IN or OUT. Check for noise from
external effects or bad cabling.
5) PROTECT MODE: The RED PROTECT LED provides the operator with information about the
status of the amplifier. The PROTECT LED can come on under 3 different conditions (when
this happens, speaker relays disconnect the speakers);
1) During power-up, the amplifier stays in a muted state for approx. 3 sec until it determines
that everything is functioning normally (no output shorts or over temp conditions).
2) The RED PROTECT LED will illuminate when the output load draws excessive current or a
direct short is detected caused by a shorted speaker cable or speaker system. Reset this con-
dition by turning the amp off for two seconds and then on again. Check for shorted cables
and that the total speaker impedance is not below 2 ohms.
3) Overheating is usually determined when the amp stops in the middle of a performance and
the RED PROTECT LED comes on. If this is the cause, leave the amp on for the fan to cool
the amp down. The amp will automatically reset within 3 minutes. The PROTECT LED will
turn off when ready. Check for the following conditions; a) The rear intake air is not restricted,
b) The intake air is not extremely warm, c) The front exhaust vents are not restricted, or d) No
excessive speaker load (try other speakers or remove speakers if you have more than one con-
nected to each channel).
Power supply protections are not indicated by the protection LED, but by the power turning
off completely. If the protected state is a thermal power supply issue or an over current power
supply issue, the power supply with reset it self and go through the same turn on cycle as
when first turned on.
1. INPUT JACK
The 1/4” INPUT jack accommodates both passive and active instruments. The high imped-
ance
Class A
input stage offers enough headroom to perform without clipping even when used
with high output active basses. Input gain is adjusted with the DRIVE control (6) and the ACTIVE
INPUT switch (5).
2. VOLUME CONTROL
The VOLUME control adjusts the output level to the speakers. Adjusting the DRIVE control
will also change your output level.
3. MUTE SWITCH/LED
The MUTE switch will stop all output signals with the exception of the TUNER and EFFECT
SEND signals. The MUTEfunction can also be remotely controlled from the rear FOOTSWITCH
jack using the optional FS22 footswitch. The blue LED next to the MUTE switch will light when-
ever the amp is muted. The footswitch will have no effect if the front panel MUTE switch is on
in the UP position.
4. CLIP LED
The red CLIP LED indicates that the input is near clipping. Since the preamp is designed with
several
Class A
input gain stages and the ability to be overdriven, the CLIP LED monitors only
the first input stage and will not indicate when the DRIVE control is set to overdrive the preamp.
To avoid input clipping, reduce the bass level or reduce the output level of devices placed between
the bass and the input jack.
5. ACTIVE INPUT SWITCH / LED
The ACTIVE INPUT switch is used to match the input gain of the amp to instruments that
contain active electronics. If the preamp is being prematurely overdriven, flip the ACTIVE INPUT
switch to the ON position. If the output of your bass is low and you are not getting enough
volume from the speakers, be sure the ACTIVE INPUT switch is OFF and increase the DRIVE
control. The blue LED indicates that the ACTIVE INPUT mode is ON.
6. DRIVE CONTROL
The DRIVE control adjusts the input gain to the preamp and the level of harmonics in the
signal. With the DRIVE control set low, both input gain and harmonics are at a minimum for
clean output. Increasing the DRIVE control causes the Class A gain stages to introduce more
harmonics resulting in a rich sound typical of vintage tube amps. With the DRIVE control set
near maximum, overdrive sounds can be produced. The DRIVE control can be used with the
ACTIVE INPUT switch to get the sound you want. To reduce preamp overdrive while retaining
the harmonics of a high DRIVE level setting, turn the ACTIVE INPUT switch ON or reduce the
level on the bass guitar. Turning the ACTIVE INPUT switch OFF will make the preamp over-
drive easier.
7. TONE CONTROLS
The six TONE CONTROLS are designed with the center frequencies most requested by pro-
fessional bass players. To start, set each control at its center flat position (no tones are cut or
boosted). Raise or reduce each control to get your desired tone.
Center Frequencies
SUB BASS 40Hz
BASS 100Hz
LO MID 400Hz
MID 800Hz
HI MID 2kHz
TREBLE 6kHz
8. EFFECT LOOP SWITCH/LED
The EFFECT LOOP switch engages the rear effects loop connections. The effects loop can be
turned on with the EFFECT LOOP switch on the front panel or by using the optional FS22
footswitch. When the front panel switch is in the UP position, the loop is engaged regardless
of the footswitch. The status of the effects loop is indicated on the front panel by the BLUE
LED next to the EFFECT LOOP switch.
See EFFECT LOOP SEND/RETURN JACKS #12.
9. AMP CLIP LED
The AMP CLIP LED indicates that the power amp is being driven too hard. Reduce the
volume level.
10. PROTECT LED
The PROTECT LED indicates that the power amp has gone into one of it’s protect modes.
11. POWER SWITCH/(PROTECT RESET)
Push the upper portion of the POWER SWITCH to turn the amplifier on. If the large blue power
indicator is on but no sound is coming out of the speakers, the amp may have gone into one
of its protection modes. To reset the amp, turn the power off for 30 seconds and then turn the
amp back on. If the problem persists, check for; a) The speaker impedance is too low for the
amp, b) bad speaker cable, c) damaged speaker or, d) blocked rear fan intake.
1
FRONT PANEL CONTROLS
REAR PANEL CONTROLS
2
3
4
5
6
7
8
9
SPEAKER COMBINATIONS and OHMS (
Ω
):
Four x 8Ω cabinets = 2Ω (OK)
Three x 8Ω = 2.66Ω (OK)
Two x 8Ω = 4Ω (OK)
Two x 4Ω = 2Ω (OK)
One 8Ω and One 4Ω cabinet = 2.66Ω (OK)
Two 8Ω and One 4Ω = 2Ω (OK)
One 2.66Ω and One 8Ω = 2Ω (OK)
Two x 2Ω = 1Ω (no)
Three x 4Ω = 1.33Ω (no)
Two x 4Ω and One 8Ω = 1.6Ω (no)
The
B2000 is a powerful amplifier. As with any amplifier, make sure your speakers
are suitable for the available wattage. Driving speakers with too much wattage will cause
them to distort and eventually fail. If distorted sound is coming from the speakers, reduce
the volume until the distortion stops.
10
11
16
13
12
14
15
12