citronic CASA Active Subwoofer Cabinets User Manual


CASA Active Subwoofer Cabinets

Item ref: CASA-10BA 178.120UK
CASA-12BA 178.122UK
CASA-15BA 178.125UK
CASA-18BA 178.128UK

User Manual


citronic casa active subwoofer


Thank you for choosing a CASA active subwoofer as part of your sound system.
This product is designed to enhance a full-range sound system with powerful sub-frequencies and transients.
Please read this manual to achieve optimum performance from your sub cabinet and avoid damage through misuse.

Package Contents

  • CASA-series active subwoofer
  • Mains lead(s)
  • User manual

If you find any part is missing or the product has arrived with any problems, please contact your retailer at once.

This product contains no user-serviceable parts, so make no attempt to try to fix or modify this item yourself as this will invalidate the warranty. We recommend you keep the original package and proof of purchase for any possible replacement or return issues.


To prevent the risk of fire or electric shock, do not expose any of the components to rain or moisture.
Avoid impact to any of the components.
No user serviceable parts inside – refer servicing to qualified service personnel.


  • Please observe the following warning conventions Safety
  • Ensure that the correct mains lead is used with adequate current rating and mains voltage is as stated on the unit
  • Avoid ingress of water or particles into any part of the housing. If liquids are spilled on the cabinet, stop using immediately, allow the unit to dry out and have checked by qualified personnel before further use.

Warning: this unit must be earthed


  • Keep the electronic parts out of direct sunlight and away from heat sources.
  • Position the cabinet on a stable surface that is adequate to support the weight of the product.
  • Allow adequate space for cooling and access to controls and connections at the rear of the cabinet.
  • Keep the cabinet away from damp or dusty environments.


  • Use a soft dry or slightly damp cloth to clean surfaces of the cabinet
  • A soft brush can be used to clear debris from controls and connections without damaging them
  • To avoid damage, do not use solvents to clean any parts of the cabinet.

Rear panel layout

  1. L+R LINE inputs combo Jack/XLR
  2. L+R full range LINE LINK outputs combo Jack/XLR
  3. L+R filtered LINE OUTPUTs combo Jack/XLR
  4. Power on/off switch
  5. Phase switch 0°/180°
  7. MASTER output level control
  8. Filtered LINE out cutoff frequency switch 80/125Hz
  9. IEC mains inlet & fuse holder

Rear Panel

Setting up

Position your CASA active subwoofer(s) on a stable surface capable of supporting the load and vibrations from the cabinet. For maximum sound delivery, position with the back close to a solid wall or in a corner of the room.

Aim the cabinet towards the audience or listeners and not in direct line of sight with any microphones that are connected to the sound system. This is to avoid feedback (howling or booming caused by the microphone “hearing” itself amplified). Also, keep microphone stands away from the subwoofer to avoid vibrations being transferred to the microphones.

If a single CASA active subwoofer is to be used with a stereo pair of active full-range speakers, connect both Left and Right outputs from the mixer into the Left + Right inputs of the CASA active subwoofer (1).

For maximum efficiency, Connect the Left + Right OUTPUT XLRs (3) to each full range speaker, which removes the lowest frequencies that are being delivered by the subwoofer, freeing up the power of the full-range top cabinets to produce upper frequencies more efficiently.

Select 80Hz or 125Hz (8) depending upon the size of cabinet. Larger cabinets can usually produce lower frequencies, so 80Hz would be a good choice for 15” top cabinets and maybe 125Hz for 8” top cabinets, depending also upon the type of program material being played through the system. Experimentation is recommended. If an unfiltered, full-range output is needed, connect the Left + Right LINK XLR outputs (2) to the full-range active speakers or amplifier. Also, use these outputs to feed to further active sub-woofers if necessary.

If there are Left + Right CASA active subwoofers in the sound system, use either Left or Right inputs and link just this one side to full-range or top cabinets (either LINK or OUTPUT).

When all signal connections are made, connect the power lead provided (or equivalent) from the mains power supply to the IEC inlet on the CASA subwoofer (9). Ensure that the mains voltage is as indicated on the rear panel of the CASA active subwoofer.


With the MASTER output level control turned fully down (7), switch on power to the CASA subwoofer (4) Ensure that a signal is playing to the input(s) and gradually increase the MASTER to the required level. The ON LED (6) stays lit to show that the unit is powered up but the SIGNAL LIMIT LED (6) should only light briefly on the loudest parts of audio (usually beats of a kick drum or other loud transients). If this LED lights for longer periods, it is advised to reduce the output level to avoid overload.

Where 2 or more subwoofers are used un the same space, if they are facing each other, the signals can cancel each other out, in this case, one of the subwoofers would need to be “phase-reversed” by switching the PHASE button (5) to the opposite setting to the other subwoofer. This phase switch can also be used to help to mitigate feedback or “lost” sub output in a room through experimenting with either setting.

Turn down the MASTER level before powering down the CASA active subwoofer to avoid loud noises and disconnect from the mains supply if not being used for long periods.



Standards Disposal: The “Cro ssed Wheelie Bin” s ymbol on the p ro duct means that the p roduct is classed as Electrical or Electronic equipment and should not be disposed with other household or commercial waste at the end of its useful life.
The goods must be disposed of according to your local council guidelines.

citronic CASA Active Subwoofer Cabinets User Manual – Optimized PDF
citronic CASA Active Subwoofer Cabinets User Manual – Original PDF

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