Monoprice 108248 8-Inch 60-Watt Powered Subwoofer User Manual

1. Introduction

Thank you for purchasing the Monoprice 108248 8-Inch 60-Watt Powered Subwoofer. This manual provides detailed instructions for the proper installation, operation, and maintenance of your new subwoofer. Please read this manual thoroughly before use and retain it for future reference.

This 8-inch powered subwoofer is designed to enhance your audio system by providing deep, impactful bass. It features a built-in 60-watt RMS amplifier and adjustable controls for seamless integration with various stereo or surround sound setups.

2. Important Safety Information

Please observe the following safety precautions to prevent damage to the unit and ensure your personal safety:

• Power Source: Connect the subwoofer only to an AC power outlet with the specified voltage (120 VAC, 60 Hz for North America).
• Ventilation: Ensure adequate ventilation around the unit. Do not block ventilation openings.
• Water and Moisture: Do not expose the unit to rain, moisture, or excessive humidity. Do not place objects filled with liquids, such as vases, on the unit.
• Heat Sources: Keep the unit away from heat sources such as radiators, heat registers, stoves, or other heat-producing appliances.
• Cleaning: Unplug the unit from the power outlet before cleaning. Use a soft, dry cloth. Do not use liquid cleaners or aerosol cleaners.
• Servicing: Do not attempt to service this product yourself. Refer all servicing to qualified service personnel.
• Placement: Place the subwoofer on a stable, level surface to prevent it from falling.

3. Package Contents

Please ensure all items are present and in good condition upon unpacking:

• Monoprice 108248 8-Inch Powered Subwoofer
• Power Cable
• RCA Audio Cable (Stereo)
• User Manual (This document)

Image: The Monoprice 108248 Powered Subwoofer shown with its packaging box and included RCA cable.

4. Product Overview

4.1 Front Panel

Image: Front view of the Monoprice 108248 Powered Subwoofer with its black cloth speaker grill attached.

The front of the subwoofer features an 8-inch driver and a 2 3/4-inch sound port, both covered by a removable black cloth speaker grill. The grill protects the driver and port while providing a clean aesthetic.

Image: Front view of the Monoprice 108248 Powered Subwoofer with the black cloth speaker grill removed, revealing the 8-inch speaker driver and the bass port.

Removing the grill reveals the 8-inch subwoofer driver and the front-firing bass port, designed to enhance low-frequency response.

4.2 Rear Panel Controls and Connections

Image: Detailed view of the rear panel of the Monoprice 108248 Powered Subwoofer, highlighting the various input/output connections and control knobs.

The rear panel houses all the necessary controls and input/output connections:

• VOLUME (Gain) Knob: Adjusts the overall output level of the subwoofer.
• FREQ (Crossover) Knob: Adjusts the low-pass crossover frequency from 50 Hz to 150 Hz. This determines the highest frequency the subwoofer will reproduce.
• POWER Switch: Toggles the subwoofer power ON or OFF.
• AUTO ON Switch: Enables or disables the automatic power-on/standby feature. When set to ON, the subwoofer will power on when an audio signal is detected and enter standby after a period of inactivity.
• HI LEVEL Input/Output: Speaker-level inputs and outputs for connecting to an amplifier's speaker terminals.
• LINE IN (L/R) Input: RCA line-level inputs for connecting to an amplifier or receiver's pre-out or subwoofer output.
• FUSE: Replaceable fuse for circuit protection.
• INPUT (AC Power): Connection for the AC power cable.

5. Setup and Connections

Proper placement and connection are crucial for optimal subwoofer performance.

5.1 Placement

Experiment with different locations in your room to find the best bass response. Generally, placing the subwoofer in a corner can enhance bass output, but may also lead to boomy sound. Placing it along a wall can provide a more balanced sound. Avoid placing it directly against a wall or in a cabinet without adequate ventilation.

5.2 Connection Options

The Monoprice 108248 subwoofer offers two primary connection methods:

5.2.1 Line Level Connection (Recommended for Receivers with Subwoofer Output)

If your amplifier or receiver has a dedicated subwoofer (LFE) output or stereo pre-out, use this method.

1. Ensure all audio equipment is powered off.
2. Connect an RCA cable (or a Y-adapter if using a single LFE output) from your receiver's subwoofer output or stereo pre-out to the LINE IN (L/R) inputs on the subwoofer's rear panel.
3. Proceed to Section 6.1 for initial settings.

Image: A pair of red and white RCA audio cables, commonly used for line-level audio connections.

5.2.2 High Level Connection (For Amplifiers without Subwoofer Output)

If your amplifier or receiver does not have a dedicated subwoofer output, you can connect the subwoofer using the speaker-level outputs.

1. Ensure all audio equipment is powered off.
2. Connect speaker wires from your amplifier's main speaker outputs (Front Left and Front Right) to the HI LEVEL Input terminals on the subwoofer. Match positive (+) to positive and negative (-) to negative.
3. Connect your main speakers from the HI LEVEL Output terminals on the subwoofer. Again, match positive (+) to positive and negative (-) to negative.
4. This method allows the subwoofer to receive a full-range signal without affecting the power output to your main speakers or the overall impedance load on your amplifier.
5. Proceed to Section 6.1 for initial settings.

6. Operation

6.1 Initial Settings

1. After making all connections, plug the subwoofer's power cable into a wall outlet.
2. Set the POWER switch to the ON position.
3. Set the AUTO ON switch to your preferred setting (ON for automatic standby, OFF for always on).
4. Set the VOLUME knob to its minimum position (fully counter-clockwise).
5. Set the FREQ (crossover) knob to its minimum position (50 Hz).
6. Power on your amplifier/receiver and start playing audio.

6.2 Adjusting Controls

Adjust the subwoofer's settings to blend seamlessly with your main speakers.

• Volume (Gain): Slowly increase the VOLUME knob until the bass output matches the level of your main speakers. The goal is to add subtle, deep bass, not to overpower the main speakers.
• Frequency (Crossover):
  • If your main speakers are small (e.g., satellite speakers), set the FREQ knob higher (e.g., 100-120 Hz) to allow the subwoofer to handle more of the mid-bass frequencies.
  • If your main speakers are larger (e.g., floor-standing speakers) and produce good bass on their own, set the FREQ knob lower (e.g., 60-80 Hz) to avoid overlapping frequencies and muddy sound.
  • Adjust this knob while listening to various music and movie content to find the optimal blend.
• Auto On/Off: When the AUTO ON switch is set to ON, the subwoofer will automatically detect an audio signal and power on. If no signal is detected for approximately 15-20 minutes, it will enter standby mode. This feature conserves energy. If you prefer the subwoofer to remain on constantly, set the switch to OFF.

7. Maintenance

The Monoprice 108248 subwoofer requires minimal maintenance.

• Cleaning: Use a soft, dry cloth to wipe the cabinet. Do not use abrasive cleaners, waxes, or solvents.
• Grill: The speaker grill can be gently removed for cleaning if necessary. Ensure it is reattached securely.
• Fuse Replacement: If the subwoofer does not power on, check the fuse on the rear panel. Unplug the unit before attempting to replace the fuse. Use only a fuse of the same type and rating (1A/250V).

8. Troubleshooting

If you experience issues with your subwoofer, consult the following table before contacting support.

9. Specifications

Image: The Monoprice 108248 Powered Subwoofer with its height, width, and depth dimensions indicated in centimeters.

10. Warranty and Support

Monoprice stands behind its products. For specific warranty information, please refer to the warranty card included with your purchase or visit the official Monoprice website.

For technical support, troubleshooting assistance, or to inquire about warranty claims, please contact Monoprice Customer Service:

• Website: www.monoprice.com/support
• Phone: Refer to the Monoprice website for regional contact numbers.

Please have your model number (108248) and purchase date available when contacting support.