1. Introduction
Thank you for choosing the Memphis Audio MB1224 12-inch MSeries MB Subwoofer. This manual provides essential information for the proper installation, operation, and maintenance of your new subwoofer. To ensure optimal performance and longevity, please read these instructions thoroughly before installation and use. This subwoofer features selectable 2 or 4 Ohm impedance, offering flexibility for various car audio system configurations.
Figure 1: Front view of the Memphis Audio MB1224 12-inch MSeries MB Subwoofer.
2. Safety Information
Always observe the following safety precautions during installation and operation:
- Disconnect the vehicle's battery before beginning any electrical work to prevent short circuits.
- Ensure all wiring is properly insulated and secured to prevent damage and electrical hazards.
- Avoid mounting the subwoofer in locations that obstruct vehicle operation or safety features.
- Use appropriate gauge wiring for power and speaker connections to handle the subwoofer's power requirements.
- Do not expose the subwoofer to excessive moisture or extreme temperatures.
- Seek professional installation if you are unsure about any steps.
3. Package Contents
Verify that all items are present in the package:
- Memphis Audio MB1224 12-inch MSeries MB Subwoofer
- Jumper cables (for impedance selection)
- Instruction Manual (this document)
4. Specifications
Key technical specifications for the MB1224 Subwoofer:
| Specification | Value |
|---|---|
| Model Name | MB1224 |
| Speaker Type | Subwoofer |
| Subwoofer Diameter | 12 Inches (30.48 cm) |
| Material | Aluminum |
| Item Weight | 13 Pounds |
| RMS Power Handling | 500 Watts |
| Peak Power Handling | 1000 Watts |
| Impedance | Selectable 2 or 4 Ohms |
| Connectivity Technology | Wired |
| Compatible Devices | Car Audio System |
| Included Components | Jumper cables |
5. Setup and Installation
Proper installation is crucial for the performance and safety of your subwoofer. If you are not experienced with car audio installation, it is highly recommended to seek professional assistance.
5.1 Mounting the Subwoofer
The MB1224 subwoofer is designed for installation in a suitable enclosure (not included). Ensure the enclosure is robust and properly sealed for optimal bass response. Secure the subwoofer firmly to the enclosure using appropriate screws, ensuring a tight seal around the mounting flange.
Figure 2: Top view of the MB1224 subwoofer, showing the cone and mounting holes.
5.2 Wiring and Impedance Selection
The MB1224 features selectable impedance (2 Ohm or 4 Ohm) using the included jumper cables. This allows you to configure the subwoofer to match your amplifier's capabilities. Always ensure your amplifier is stable at the selected impedance.
5.2.1 4 Ohm Wiring Configuration
To configure the subwoofer for a 4 Ohm load, connect the included jumper cable between the two positive terminals and another jumper cable between the two negative terminals. Then, connect your amplifier's positive output to one of the positive terminals and the amplifier's negative output to one of the negative terminals. Refer to Figure 3 for a visual guide.
Figure 3: Rear view of the MB1224 subwoofer showing the 4 Ohm wiring configuration using jumper cables.
5.2.2 2 Ohm Wiring Configuration
To configure the subwoofer for a 2 Ohm load, connect the included jumper cable from the positive terminal of one voice coil to the negative terminal of the other voice coil. Then, connect your amplifier's positive output to the remaining positive terminal and the amplifier's negative output to the remaining negative terminal. Refer to Figure 4 for a visual guide.
Figure 4: Rear view of the MB1224 subwoofer showing the 2 Ohm wiring configuration using jumper cables.
5.2.3 Terminal Block Overview
The subwoofer features a robust terminal block for secure connections. Ensure all connections are tight and free from corrosion.
Figure 5: Close-up view of the MB1224 subwoofer's terminal block, indicating wiring options.
6. Operating Instructions
6.1 Break-in Period
Allow a break-in period of approximately 10-20 hours of normal listening before operating the subwoofer at high volumes. This allows the suspension components to loosen and achieve optimal performance.
6.2 Amplifier Settings
Properly setting your amplifier's gain, crossover, and bass boost is critical. Start with the gain at its lowest setting and slowly increase it until you achieve the desired volume without distortion. Set the low-pass filter (LPF) on your amplifier to prevent high frequencies from reaching the subwoofer, typically between 80Hz and 120Hz. Avoid excessive bass boost, as this can lead to distortion and potential damage.
7. Maintenance
The Memphis Audio MB1224 subwoofer requires minimal maintenance:
- Periodically inspect the subwoofer cone and surround for any signs of damage or wear.
- Ensure all wiring connections remain secure and free from corrosion.
- Clean the subwoofer's exterior with a soft, dry cloth. Do not use harsh chemicals or abrasive cleaners.
- Keep the subwoofer free from dust and debris, especially if it is not enclosed.
8. Troubleshooting
If you experience issues with your subwoofer, refer to the following common problems and solutions:
| Problem | Possible Cause | Solution |
|---|---|---|
| No sound from subwoofer | No power to amplifier, incorrect wiring, amplifier in protect mode, low input signal. | Check amplifier power and ground connections. Verify all speaker wires are correctly connected and secure. Check amplifier fuses. Ensure head unit is sending a signal. |
| Distorted or unclear sound | Amplifier gain set too high, incorrect crossover settings, damaged subwoofer, poor enclosure. | Reduce amplifier gain. Adjust LPF settings. Inspect subwoofer cone and surround for damage. Ensure enclosure is sealed and properly sized. |
| Subwoofer cuts out intermittently | Loose wiring connections, amplifier overheating, impedance mismatch. | Check all wiring connections for tightness. Ensure amplifier has adequate ventilation. Verify subwoofer impedance matches amplifier's stable operating range. |
| Subwoofer is too quiet | Amplifier gain too low, incorrect phase setting, low input signal. | Increase amplifier gain gradually. Check phase setting on amplifier or head unit. Ensure head unit volume is adequate. |
If the problem persists after attempting these solutions, contact Memphis Audio customer support or a qualified car audio technician.
9. Warranty and Support
Memphis Audio products are designed and manufactured to the highest standards. This product comes with a limited warranty. For specific warranty terms and conditions, please refer to the warranty card included with your purchase or visit the official Memphis Audio website. For technical support or service inquiries, please contact Memphis Audio customer service directly.
