Model: 124457
Thank you for purchasing the Monolith 12 Inch Powered Subwoofer. This subwoofer is engineered to deliver exceptional bass performance for both professional studio environments and home theater systems. Featuring a 500 Watt amplifier and THX certification, it provides powerful, low-distortion audio that enhances any listening experience. This manual provides essential information for setup, operation, and maintenance to ensure optimal performance and longevity of your subwoofer.
Please read and understand all safety instructions before operating this device. Keep this manual for future reference.
Carefully unpack the contents and ensure all items are present and in good condition.
The Monolith 12 Inch Powered Subwoofer is designed for optimal audio performance. Below are key components and features.

This image displays the front of the subwoofer, highlighting the prominent 12-inch woofer and the dual front-firing ports. The Monolith logo is visible on the speaker cone. The cabinet features a sleek black finish.

The rear panel houses all the necessary connections and controls for the subwoofer. This includes inputs for audio signals, power input, and various adjustment knobs for fine-tuning the sound. Key controls typically include Crossover, Phase, and Level (volume).

This diagram illustrates the physical dimensions of the subwoofer, which are approximately 32 inches (D) x 22.5 inches (W) x 30 inches (H). Please ensure you have adequate space for placement.
Proper setup is crucial for optimal performance. Follow these steps for initial installation.
Before making any connections, ensure the subwoofer and all connected audio equipment are turned off and unplugged from the power outlet.
After setup, you can power on your subwoofer and begin fine-tuning its performance.
Note: For THX certified performance, it is recommended to use an AV receiver with THX bass management and set the subwoofer's controls according to THX guidelines, typically with crossover set to LFE and phase at 0 degrees.
To ensure the longevity and optimal performance of your Monolith subwoofer, follow these maintenance guidelines:
If you encounter issues with your subwoofer, refer to the following common problems and solutions:
| Problem | Possible Cause | Solution |
|---|---|---|
| No Sound from Subwoofer |
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| Distorted or Boomy Bass |
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| Weak or Muffled Bass |
|
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| Humming or Buzzing Noise |
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If the problem persists after trying these solutions, please contact customer support.
Detailed technical specifications for the Monolith 12 Inch Powered Subwoofer.
| Feature | Specification |
|---|---|
| Model Number | 124457 |
| Speaker Type | Powered Subwoofer |
| Woofer Diameter | 12 Inches |
| Amplifier Power (RMS) | 500 Watts |
| Amplifier Power (Peak) | 1000 Watts |
| THX Certification | THX Ultra Certified |
| Connectivity Technology | RCA, XLR |
| Product Dimensions (D x W x H) | 32"D x 22.5"W x 30"H |
| Item Weight | 103 Pounds |
| Color | Black |
| UPC | 889028055953 |
For warranty information and technical support, please refer to the official Monoprice website or contact their customer service directly. Keep your purchase receipt as proof of purchase for warranty claims.
Monoprice Customer Support:
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