1. Introduction
Thank you for choosing the Memphis Audio MOJO1512 MOJO 7 Series 15-inch Component Subwoofer. This manual provides essential information for the proper installation, operation, and maintenance of your new subwoofer. Please read this manual thoroughly before attempting installation or operation to ensure optimal performance and longevity of your product.
2. Safety Information
Always observe the following safety precautions when installing and operating your subwoofer:
- Disconnect the vehicle's battery negative terminal before beginning any electrical work.
- Ensure all wiring is properly insulated and secured to prevent short circuits and damage.
- Use appropriate gauge wiring for power and speaker connections as recommended by your amplifier manufacturer.
- Avoid mounting the subwoofer in locations that obstruct vehicle operation or safety features.
- Do not expose the subwoofer to excessive moisture or extreme temperatures.
- Seek professional installation if you are unsure about any steps.
- WARNING: This product can expose you to chemicals including lead, which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.
3. Features
The MOJO1512 subwoofer incorporates advanced design and materials for superior performance:
- Lightweight Polypropylene Cone for responsive bass.
- Double-stitched Folded Rubber Surround for durability and excursion.
- Vented Cast Aluminum Basket for enhanced cooling and structural integrity.
- 3.5" Aluminum Triple Voice Coil for high power handling.
- Selectable 1-ohm or 2-ohm impedance for versatile amplifier matching.
4. Specifications
| Specification | Value |
|---|---|
| Model Name | MOJO1512 |
| Speaker Type | Component Subwoofer |
| Subwoofer Diameter | 15 Inches |
| Power Handling (RMS) | 1500 Watts |
| Power Handling (Peak) | 3000 Watts |
| Impedance | Selectable 1 Ohm or 2 Ohm |
| Product Dimensions (D x W x H) | 18.1" x 18.3" x 13.6" |
| Item Weight | 41 Pounds |
| Connectivity Technology | Wired |
| Recommended Use | Car Audio Systems |
5. Setup and Installation
5.1. Enclosure and Mounting
The MOJO1512 subwoofer is designed for use in a custom-built or pre-fabricated subwoofer enclosure. Consult with a car audio professional or refer to Memphis Audio's recommended enclosure specifications for optimal performance. Ensure the enclosure is robust and sealed properly (for sealed enclosures) or ported correctly (for ported enclosures).
Mount the subwoofer securely to the enclosure using appropriate fasteners. Ensure there is adequate clearance for the subwoofer's excursion and proper ventilation for the motor structure.
5.2. Wiring and Impedance Selection
The MOJO1512 features a triple voice coil design with selectable impedance, allowing you to configure the subwoofer for either a 1-ohm or 2-ohm final load. This flexibility enables optimal matching with a wide range of amplifiers. Refer to the diagram on the subwoofer's terminal block and the image below for correct wiring configurations.
Important: Always ensure your amplifier is stable at the chosen impedance. Incorrect wiring or an unstable amplifier can lead to damage to both the subwoofer and the amplifier.
- 1 Ohm Wiring: Connect the voice coils in parallel as indicated by the '1Ω WIRING' diagram on the terminal block. This configuration presents a 1-ohm load to the amplifier.
- 2 Ohm Wiring: Connect the voice coils in series-parallel as indicated by the '2Ω WIRING' diagram on the terminal block. This configuration presents a 2-ohm load to the amplifier.
After wiring, connect the subwoofer to your amplifier's subwoofer output terminals, ensuring correct polarity (+ to + and - to -).
6. Operating Instructions
6.1. Initial Break-in Period
Allow a break-in period of approximately 20-30 hours of normal listening before operating the subwoofer at high volumes. This allows the suspension components (surround and spider) to loosen up and reach their optimal compliance, improving performance and longevity.
6.2. Amplifier Gain Setting
Properly setting your amplifier's gain is crucial. Start with the amplifier gain at its minimum setting. Play a test tone or music with strong bass content. Slowly increase the gain until you hear distortion, then back off slightly. Never use the gain control as a volume knob; it should be set to match the output voltage of your head unit.
6.3. Crossover and Subsonic Filter Settings
Utilize your amplifier's or head unit's low-pass filter (LPF) to ensure the subwoofer only reproduces low frequencies. A typical setting for a 15-inch subwoofer might be between 60Hz and 80Hz. Additionally, use a subsonic filter (high-pass filter for the subwoofer) to protect the subwoofer from playing frequencies below its resonant frequency, which can cause damage. A common setting is 25Hz to 30Hz.
7. Maintenance
The MOJO1512 subwoofer requires minimal maintenance:
- Keep the subwoofer cone and surround clean and free of dust and debris. Use a soft, dry cloth for cleaning.
- Periodically check all wiring connections to ensure they are secure and free from corrosion.
- Ensure the subwoofer is not exposed to direct sunlight for prolonged periods, which can degrade the surround material.
8. Troubleshooting
If you experience issues with your MOJO1512 subwoofer, consider the following common problems and solutions:
| Problem | Possible Cause | Solution |
|---|---|---|
| No Sound from Subwoofer | No power to amplifier; Amplifier in protect mode; Loose wiring connections; Incorrect input signal. | Check amplifier power, ground, and remote turn-on connections. Verify amplifier fuses. Inspect all speaker and RCA connections. Ensure head unit is sending a signal. |
| Distorted Sound | Amplifier gain set too high; Incorrect crossover settings; Subwoofer over-excursion; Damaged voice coil. | Reduce amplifier gain. Adjust LPF and subsonic filter settings. Ensure enclosure is appropriate. If distortion persists at low volumes, the subwoofer may be damaged. |
| Weak or Muffled Bass | Incorrect wiring polarity; Amplifier gain too low; Improper enclosure; Phase issues. | Verify speaker wire polarity (+ to +, - to -). Increase amplifier gain gradually. Check enclosure integrity. Adjust phase setting on amplifier/head unit if available. |
| Subwoofer Overheating | Amplifier clipping; Under-powered amplifier; Incorrect impedance match; Insufficient ventilation. | Reduce amplifier gain to eliminate clipping. Ensure amplifier power matches subwoofer RMS rating. Verify correct impedance wiring. Provide adequate airflow around the subwoofer and amplifier. |
If these steps do not resolve the issue, contact Memphis Audio customer support or a qualified car audio technician.
9. Warranty and Support
The Memphis Audio MOJO1512 subwoofer comes with a limited warranty. Please refer to the warranty card included with your product or visit the official Memphis Audio website for detailed warranty terms and conditions. Keep your proof of purchase for warranty claims.
For technical support, troubleshooting assistance, or warranty inquiries, please contact Memphis Audio customer service through their official website or authorized dealer network.