KEF REFERENCE 8b Owner's Manual

Introduction

Congratulations on your purchase of the KEF REFERENCE 8b subwoofer. This manual provides essential information for setting up, connecting, and operating your new subwoofer. Please read this manual fully before attempting any connections to the REFERENCE 8b.

Important Safety Instructions

WARNING: TO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK, DO NOT EXPOSE THIS APPLIANCE TO RAIN OR MOISTURE.

CAUTION: TO REDUCE THE RISK OF ELECTRIC SHOCK, DO NOT REMOVE COVER. NO USER-SERVICEABLE PARTS INSIDE. REFER SERVICING TO QUALIFIED SERVICE PERSONNEL.

Explanation of Graphical Symbols:

• The lightning flash with arrowhead symbol, within an equilateral triangle, is intended to alert the user to the presence of uninsulated "dangerous voltage" within the product's enclosure that may be of sufficient magnitude to constitute a risk of electric shock to persons.
• The exclamation point within an equilateral triangle is intended to alert the user to the presence of important operating and maintenance (servicing) instructions in the literature accompanying the appliance.

WARNING:

• This product must be connected to a mains socket outlet with a protective earthing connection.
• The mains plug serves as the disconnect device. The disconnect device shall remain readily operable.

Read Instructions: All the safety and operating instructions should be read before the appliance is operated.

Retain Instructions: The Safety and Operating instructions should be retained for future reference.

Heed Warnings: All warnings on the appliance and in the operating instructions should be adhered to.

Follow Instructions: All operating and use instructions should be followed.

Water and Moisture: Do not use this appliance near water. For example, do not use it in a wet basement or near a swimming pool, and the like.

Cleaning: Unplug this appliance from the mains socket outlet before cleaning. Use a dry cloth only. Do not use liquid or aerosol cleaners.

Heat: The appliance should be situated away from heat sources such as radiators, heat registers, stoves, or other appliances that produce heat.

Ventilation: Do not block any ventilation openings. For example, the appliance should not be placed on a bed, sofa, rug, or similar surface that may block the ventilation openings. The appliance should not be placed in a built-in installation, such as a bookcase or cabinet that may impede the flow of air.

Power Cord Protection: Power-supply cords should be routed so that they are not likely to be walked on or pinched by items placed upon or against them, paying particular attention to cords at the plugs, convenience receptacles, and the point where they exit from the appliance.

Attachments: Do not use attachments not recommended by the product manufacturer as they may cause hazards.

Carton and Stand: Do not place this appliance on an unstable cart, stand, tripod, bracket, or table. The appliance may fall, causing serious injury to a child or adult, and serious damage to the appliance. Use only with a cart, stand, tripod, bracket or table recommended by the manufacturer, or sold with the appliance. Any mounting of the appliance should follow the manufacturer's instructions and should use a mounting accessory recommended by the manufacturer.

Product Moving: A cart and appliance combination should be moved with a quick stop,S-turn or more moves. Quick stops, S-turns, or more moves may cause the appliance to overturn.

Power Sources: This appliance should be operated only from the type of power source indicated on the marking label.

Grounding or Polarization: This appliance is equipped with a polarized alternating current mains plug (a plug having one blade wider than the other). This plug will fit into the outlet only one way. This is a safety feature. If you are unable to insert the plug fully into the outlet, try reversing the plug. If it still does not fit, contact your electrician to replace your obsolete outlet. Do not defeat the safety purpose of the polarized plug.

Overloading: Do not overload mains outlets and extension cords. This can result in a risk of fire or electric shock.

Servicing: Do not attempt to service this appliance yourself. Opening or removing covers may expose you to dangerous voltage or other hazards. Refer all servicing to qualified service personnel.

Replacement Parts: When replacement parts are required, ensure that the service technician has used replacement parts specified by the manufacturer or have the same characteristics as the original part.

Safety Check: Upon completion of any service or repairs to this appliance, ask the service technician to perform safety checks to determine that the appliance is in proper operating condition.

Inside the Box

Your KEF REFERENCE 8b package contains:

• 1 x REFERENCE 8b Subwoofer
• 1 x Power Cable
• 1 x Owner's Manual
• 1 x Safety Information Guide
• 1 x Set of connection cables (may vary)
• 1 x Set of accessories (e.g., spikes, rubber feet)

Unpacking

Follow these steps to unpack your subwoofer:

1. Carefully open the box and remove the subwoofer. It is recommended to have assistance for lifting.
2. Remove all accessories and packaging materials from the box.
3. Place the subwoofer on a stable surface in its intended location.

Positioning

Proper placement of your subwoofer is crucial for optimal performance. Consider the following guidelines:

• Corner Placement: Placing the subwoofer in a corner can increase bass output due to room boundary reinforcement.
• Front Wall Placement: Placing the subwoofer along the front wall can provide a balanced bass response.
• Mid-Room Placement: Avoid placing the subwoofer exactly in the middle of the room or exactly halfway between walls, as this can create uneven bass response (room modes).
• Stereo and Surround Setups: For stereo systems, place the subwoofers symmetrically with the main speakers. For surround sound systems, position the subwoofer(s) to complement the main and surround speakers, ensuring smooth integration of bass frequencies.

Refer to the diagrams for typical placement scenarios:

Diagram Description 1: A single REFERENCE 8b subwoofer is shown placed in a room corner.

Diagram Description 2: Two REFERENCE 8b subwoofers are shown placed in opposite room corners.

Diagram Description 3: Four REFERENCE 8b subwoofers are shown placed in the corners of a room.

Diagram Description 4: A single REFERENCE 8b subwoofer is shown placed near the front left speaker.

Diagram Description 5: Two REFERENCE 8b subwoofers are shown placed near the front left and front right speakers.

Diagram Description 6: Four REFERENCE 8b subwoofers are shown placed in a multi-speaker configuration.

Diagram Description 7 (Stereo): Illustrates a stereo setup with two subwoofers (REFERENCE 8b) positioned alongside main speakers (e.g., REFERENCE 1, REFERENCE 3, REFERENCE 5).

Diagram Description 8 (Surround Sound): Depicts a surround sound system with subwoofers (REFERENCE 8b) integrated with front left (LF), front right (RF), rear left (LR), and rear right (RR) speakers.

Diagram Description 9 (Home Theater): Shows a home theater setup with multiple speakers, including subwoofers (REFERENCE 8b), positioned for an immersive audio experience.

Connections

Connect your REFERENCE 8b subwoofer using one of the following methods:

Line-in

Connect the Line-out or Pre-out from your amplifier or AV receiver to the Line-in RCA sockets on the subwoofer using standard RCA cables. Connect the Left (L) and Right (R) channels.

Analog XLR

If your source equipment features balanced XLR outputs, connect them to the XLR inputs on the subwoofer using XLR cables. Connect the Left (L) and Right (R) channels.

LFE (Low Frequency Effects)

For the most direct connection, use the LFE input. Connect the LFE output from your AV receiver or processor to the LFE input on the subwoofer using a subwoofer cable.

For small speakers with limited bass:

Speaker Level Inputs

If your amplifier does not have line-level outputs, you can use the speaker level inputs. Connect the speaker outputs from your amplifier to the speaker level inputs on the subwoofer using appropriate speaker wire.

Link out

You can link multiple REFERENCE 8b subwoofers together using the Link out sockets to achieve higher sound pressure levels or to distribute bass more evenly in larger rooms.

Controls and Sockets

The rear panel of the KEF REFERENCE 8b features several controls and connection sockets:

• 1. AC Power: Connection for the mains power cable.
• 2. Power Switch: Turns the subwoofer on or puts it into standby mode.
• 3. Volume Control: Adjusts the subwoofer's output level.
• 4. RCA Line Input: Connects to the Line-out or Pre-out of your source equipment.
• 5. Speaker Level Inputs: Connects to the speaker outputs of your amplifier.
• 6. Subwoofer Settings: Contains controls for Low Pass Mode, Low Frequency Level, Polarity, and Crossover Frequency.
• 7. Link Out: For connecting to other subwoofers.
• 8. Crossover Frequency (for manual mode only): Adjusts the crossover point when using manual mode.
• 9. Low Pass Filter Mode: Selects the low-pass filter mode (e.g., Bypass, Reference, Custom).

Diagram Description: A detailed illustration of the rear panel showing the placement and labeling of each control and socket.

Subwoofer Settings

1. AC Power: Connect the supplied power cable to the AC Power socket and a mains outlet.
2. Power Switch: Set the switch to ON to power up the subwoofer. Set to STANDBY for standby mode.
3. Voltage Selector: Ensure the voltage selector is set to the correct voltage for your region.
4. Inputs and Outputs: Connect your source equipment using the appropriate input sockets (Line-in, XLR, LFE, Speaker Level).
5. Low Pass Mode:
   • Bypass: Use when the subwoofer is connected via LFE and your AV processor handles the crossover.
   • Reference: Recommended setting for most systems.
   • Custom: Allows manual adjustment of crossover frequency and slope.
6. Low Frequency Level: Adjust this control to match the subwoofer's output level with your main speakers.
7. Polarity: Typically set to positive (+). Adjust if bass response is weak or indistinct.
8. Crossover Frequency (for manual mode only): Adjust the crossover frequency to blend the subwoofer with your main speakers. A common starting point is 80Hz.
9. Low Pass Filter Slope: Select the slope of the low-pass filter (e.g., 12dB/octave, 24dB/octave) for smooth integration.

Diagram Description: A graph illustrating different low-pass filter slopes (e.g., 12dB, 18dB, 24dB per octave) against frequency, showing how the subwoofer's output rolls off.

Specifications

For further information and troubleshooting, please visit the KEF website at www.kef.com.