Introduction
This manual provides essential information for the safe and efficient operation of your Hk Audio PREM-PRO-210-SUB-D2 Active Subwoofer. This 600-watt, 2 x 10-inch active subwoofer is designed to deliver impressive bass response and powerful kick, suitable for various audio setups. Please read this manual thoroughly before operating the device and keep it for future reference.
Safety Instructions
Always observe the following safety precautions to prevent electric shock, fire, or damage to the unit:
- Power Source: Connect the subwoofer only to the specified voltage and frequency as indicated on the unit. Ensure the power cord is securely plugged into a grounded outlet.
- Ventilation: Do not block ventilation openings. Ensure adequate airflow around the unit to prevent overheating.
- Moisture: Do not expose the unit to rain or moisture. Avoid placing liquids on or near the subwoofer. This product is not water resistant.
- Placement: Place the subwoofer on a stable, level surface. Avoid extreme temperatures, direct sunlight, and strong vibrations.
- Servicing: Do not attempt to service this product yourself. Refer all servicing to qualified service personnel.
- Cables: Route all cables carefully to prevent tripping hazards and damage.
Package Contents
The package for your Hk Audio PREM-PRO-210-SUB-D2 Active Subwoofer should contain the following items:
- Hk Audio PREM-PRO-210-SUB-D2 Active Subwoofer
- Power Cord
- User Manual (this document)
Setup
1. Physical Placement
The PREM-PRO-210-SUB-D2 is designed for floor standing placement. For optimal bass performance, consider placing the subwoofer in a corner or near a wall to enhance bass response. Experiment with different positions to find the best sound for your environment. Ensure the unit is stable and not obstructing any pathways.

Figure 1: Front view of the Hk Audio PREM-PRO-210-SUB-D2 Active Subwoofer, showcasing its protective grille and compact design. This image helps visualize the unit's appearance for placement considerations.

Figure 2: Diagram illustrating the dimensions of the Hk Audio PREM-PRO-210-SUB-D2 Active Subwoofer (20.9"D x 14.6"W x 24.4"H). This is useful for planning the physical space required for installation.
2. Connections
The PREM-PRO-210-SUB-D2 features XLR connectivity for audio input and output. It also includes two mid/high outputs and an adjustable frequency separation, allowing for easy integration into a 2.1 system, even with active tops that lack their own filtering.
- Audio Input: Connect your audio source (e.g., mixer, audio interface) to the subwoofer's XLR input.
- Mid/High Outputs: If using a 2.1 system, connect your active mid/high speakers to the subwoofer's "Line Out Mid/High" XLR outputs.
- Power Connection: Connect the supplied power cord to the subwoofer's power inlet and then to a suitable grounded electrical outlet.

Figure 3: Detailed view of the rear panel of the Hk Audio PREM-PRO-210-SUB-D2. This image highlights the XLR input/output connections, power inlet, and control knobs for gain, phase, and crossover frequency, essential for proper setup and operation.
Operating Instructions
1. Power On/Off
After all connections are made, switch on the subwoofer using the power switch located on the rear panel. It is recommended to power on your subwoofer last and power it off first in your audio chain to prevent pops or thumps.
2. Controls
The rear panel (refer to Figure 3) provides access to the following controls:
- Gain: Adjusts the overall output level of the subwoofer. Start with a low setting and gradually increase until the bass blends seamlessly with your main speakers.
- Phase: A 0°/180° phase switch helps align the subwoofer's output with your main speakers. Experiment with both settings to find the one that produces the most coherent and impactful bass.
- Crossover Frequency: This knob allows you to select the frequency point (75 Hz - 150 Hz) at which the subwoofer handles low frequencies, while frequencies above this point are sent to the mid/high outputs. Adjust this to match the low-frequency capabilities of your main speakers.
- Bass Boost: This special feature enhances the low-frequency response, providing a more pronounced bass impact. Use sparingly and adjust to taste.
Maintenance
To ensure the longevity and optimal performance of your subwoofer, follow these maintenance guidelines:
- Cleaning: Use a soft, dry cloth to clean the exterior of the unit. Do not use abrasive cleaners, solvents, or waxes.
- Ventilation: Regularly check that the ventilation openings are free from dust and debris.
- Storage: If storing the unit for an extended period, disconnect it from power and store it in a cool, dry place, protected from dust.
- Inspection: Periodically inspect the power cord and audio cables for any signs of damage. Replace damaged cables immediately.
Troubleshooting
If you encounter issues with your subwoofer, refer to the following common problems and solutions:
| Problem | Possible Cause | Solution |
|---|---|---|
| No Sound |
|
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| Distorted Sound |
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| Weak Bass |
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If the problem persists after trying these solutions, please contact Hk Audio customer support or a qualified service technician.
Specifications
| Model Name | PREM-PRO-210-SUB-D2 |
| Brand | Hk Audio |
| Speaker Type | Subwoofer |
| Speaker Maximum Output Power | 600 Watts |
| Subwoofer Diameter | 10 Inches (x2) |
| Crossover Frequency | 75 Hz - 150 Hz, selectable |
| Connectivity Technology | XLR |
| Audio Output Mode | Mono |
| Special Feature | Bass Boost |
| Mounting Type | Floor Standing |
| Product Dimensions (D x W x H) | 20.9" x 14.6" x 24.4" |
| Item Weight | 60 Pounds |
| Power Source | Corded Electric |
| Cabinet Features/Rigging | 2 x M20 pole mount |
| Front Grille | Steel, backed with acoustic foam |
Warranty and Support
The Hk Audio PREM-PRO-210-SUB-D2 Active Subwoofer comes with a Limited Warranty. For specific terms and conditions of your warranty, please refer to the documentation included with your purchase or visit the official Hk Audio website.
For technical support, service inquiries, or further assistance, please contact Hk Audio customer support. Contact information can typically be found on the manufacturer's official website or on your purchase receipt.
Manufacturer: HK Audio







