Blackstar U250 Owner's Manual page 9

Unity Pro Bass U250ACT Active Cabinet
Thank you for purchasing this Blackstar Unity Pro Bass U250ACT Active Cabinet.
The U250ACT Active Cabinet can be connected to any model in the Unity Pro
Bass Series to add 250W of active power to your rig; taking you from the studio
or rehearsal room to the gig with ease and portability. The U250ACT can also be
used standalone with external preamps, amp modellers or effects processors,
and multiple U250ACT Active Cabinets can be linked together for near-limitless
expansion of your setup.
U250ACT Rear Panel
ACTIVE SETUP
1. Power Switch
This switch is used to turn your U250ACT Active Cabinet on and off.
2. Mains Input
The supplied detachable mains power cable is connected here. Always ensure the
Power Switch (1) is in the OFF position before applying mains power. The cable
should only be connected to a power outlet that is compatible with the voltage,
power and frequency requirements stated on the rear panel. Never break off
the earth (ground) pin on the mains cable. If in doubt get advice from a qualified
technician.
3. Power Indicator
The Power Indicator will be illuminated when the Active Cabinet is switched on.
4. Cabinet Link/Line Input
This is the balanced audio input to your Unity Pro Bass U250ACT Active Cabinet.
Connect the Cabinet Link output from any Unity Pro Bass combo here using an
XLR cable (supplied).
Your U250ACT Active Cabinet can also be connected to most external preamps,
amp modellers or effects processors for live use, with up to 250W of power. Simply
connect the output of the external equipment to this input of your U250ACT using
an XLR cable or ¼" instrument cable.
5. Cabinet Link/Line Thru
The audio signal connected to the Cabinet Link/Line Input (4) is sent directly to this
Thru output to allow further extension of your setup by connecting additional Unity
Pro Bass U250ACT Active Cabinets. Connect a good quality standard XLR female
to XLR male cable from this output to the Cabinet Link/Line Input of an additional
Unity Pro Bass U250ACT Active Cabinet. Each additional U250ACT connected in
the chain adds 250W of power to your setup.
6. Ground Lift
This switch can be used to remove the circuit-to-chassis ground connection of the
Cabinet Link Thru (5), which can help if experiencing hum or noise upon connecting
to an additional U250ACT Active Cabinet or any other suitable external device. If
you do experience a hum engage the Ground Lift by depressing the button to lift
the ground on the circuit.
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7. Volume
This knob controls the independent volume level of your U250ACT Active Cabinet.
When connected to the Cabinet Link output of any Unity Pro Bass combo set this
control to maximum and adjust the overall volume of your setup using the Master
Volume knob to achieve the maximum possible power. Alternatively, reduce this
control to balance the volume with your Unity Pro Bass combo to achieve a quieter
sound, but with the extended bass response of an additional 15" Eminence Opus
speaker. The level of the Cabinet Link Thru output is not affected by this Volume
control.
IMPORTANT - Do not connect a cable to the Passive Speaker Input (8) when using
as an ACTIVE speaker cabinet with mains power applied. Doing so could cause
damage to your U250ACT.
ACTIVE:
✖
PASSIVE
8. Speaker Input
Your U250ACT Active Cabinet can also be used as a traditional passive speaker
cabinet for connection to amplifiers with their own internal power amplifier. Connect
a good quality speaker cable from an external amplifier here. In this passive
configuration your U250ACT is rated at 250W and has a 4 ohm impedance. Always
ensure the external amplifier driving your U250ACT is capable of operating at 4
ohms and does not exceed 250W output power. Failure to do so could cause
damage to your external amplifier and U250ACT.
IMPORTANT - Do not connect power when using as a PASSIVE speaker cabinet,
to avoid damage to your Unity Pro Bass U250ACT.
PASSIVE:
✔
✔
✖
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