Rockford Fosgate M1D4-12B M1 Series 12" 300W RMS (1200W Peak Power Handling) 4 Ohm, Dual Voice Coil RGB Marine Subwoofer (Black)
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What's Inside?
- • 12" M1 Series RGB Marine Subwoofer (Black)
- • 11" LED power harnesses with 4-pin Deutsch connector on one end
- • (6) 2" Stainless steel Allen head screws
- • 4mm Allen head bit
- • 4.5mm Drill bit
- • Owner's Manual
Built to Handle Harsh Marine Conditions
The Rockford Fosgate M1D4-12B is made for environments where durability is not optional. It is tested to ASTM B117 salt fog and ASTM G154 UV standards, so it is built to resist corrosion, moisture, and constant sun exposure without losing performance. Whether it is installed on a boat or in an open-air setup, this subwoofer is designed to stay reliable and keep delivering strong, consistent bass in real marine conditions.
Flexible Power and Easy System Matching
This sub gives you the kind of flexibility that makes system setup simple. The selectable dual impedance configuration lets you switch between 2 ohms and 8 ohms by wiring the dual 4 ohm voice coils in series or parallel, while still delivering solid output at 300W RMS and 1200W peak power. It also supports sealed, ported, and infinite-baffle installations, giving you the freedom to tune your system exactly the way you want for the kind of bass response you prefer.
Clean Bass Performance With Custom Style
The M1D4-12B combines strong performance with a clean, customizable look. The RGB lighting system behind the grille lets you choose colors like aqua, pink, yellow, or white to match your setup, while the waterproof Deutsch connector keeps everything sealed and marine ready. VAST technology increases cone efficiency for stronger bass without increasing size, and Klippel Verified engineering keeps distortion low and sound accuracy tight. With stainless steel corrosion-resistant hardware and flexible wiring options, this subwoofer delivers deep, controlled bass and long-term reliability with a style that stands out.
Frequently Asked Questions (FAQ)
- • Why Does My M1D4-12B Sound Different After Breaking In?
The sound can change slightly as the suspension settles during normal use, but a major change in output should not be attributed automatically to break-in. Check the amplifier settings, wiring, and enclosure if the bass changes dramatically.
- • Why Does the Subwoofer Seem Too Quiet With My Factory Stereo?
A factory head unit may provide a lower or processed subwoofer signal than an aftermarket source. Check the signal level going into the amplifier and make sure the input sensitivity and crossover are properly adjusted before increasing gain.
- • Why Does My M1D4-12B Make a Popping Sound When I Start the System?
A startup pop can originate from the head unit, signal processor, amplifier turn-on circuit, or remote wire. If the pop happens consistently, inspect the signal and remote-turn-on sequence rather than assuming the subwoofer is defective.
- • Why Does My Amplifier Shut Off When I Increase the Bass?
A protection shutdown can occur when the amplifier sees an unsuitable load, overheats, or encounters a power or grounding problem. The M1D4-12B can be configured for 2Ω or 8Ω, so confirm the VERSA switch setting matches the amplifier's supported impedance. Real-world users have reported amplifiers cutting out when the final speaker load is below what the amp can safely handle.
- • Why Is the Bass Strong Inside the Vehicle but Weak Outside?
Low-frequency sound can be perceived very differently depending on where the listener is standing. Vehicle panels, cabin pressure, and subwoofer orientation can create significantly more bass inside the listening area than outside.
- • What Causes the M1D4-12B to Sound Like It Is Bottoming Out?
A knocking or hard mechanical sound during deep bass can indicate excessive cone excursion. Reduce the gain and bass boost, check the crossover settings, and make sure the amplifier is not sending excessive low-frequency energy to the woofer.
- • Why Does My Enclosure Vibrate More Than the Subwoofer?
A powerful 12-inch woofer can reveal weak enclosure construction or loose panels. Inspect the box joints, mounting screws, grille, and surrounding surfaces for flexing or rattling components instead of assuming the driver itself is producing the noise.
- • Why Does the M1D4-12B Have Less Bass in My New Enclosure?
Enclosure volume has a major effect on subwoofer behavior. Rockford recommends approximately 1.65 cu. ft. for a sealed enclosure and 2.45 cu. ft. for a vented enclosure, so a box that is substantially different can produce a noticeably different response.
- • Why Are the RGB Lights Not Matching the Color I Selected?
The Color Optix LEDs require the appropriate controller and app configuration. If the audio works but the lighting displays the wrong color or effect, check the RGB controller, cable connections, power supply, and RF Connect app settings separately from the speaker wiring.
- • Why Does My M1D4-12B Get Quiet After the System Has Been Playing for Hours?
A gradual reduction in output can be related to amplifier thermal protection, voltage drop, or a connection becoming unstable as components heat up. Check the amplifier temperature, battery voltage, power/ground connections, and speaker impedance before diagnosing the woofer. Users commonly report excessive amplifier heat during extended high-output sessions.
- Diameter : 12 Inch
- Sensitivity : 92 dB
- Impedance : 4 Ohm
- Frequency Response : 20-750 Hz
- RMS Power Range : 300 Watts
- Peak Power Handling : 1200 Watts
- Color : Black
- Mounting Depth : 6.65 Inches
Features:
- Marine Environmental Durability: Tested to ASTM B117 salt/fog and ASTM G154 UV standards to ensure reliable performance and resistance to harsh marine elements.
- Selectable Dual Impedance Configuration: Integrated switch allows easy selection between 2Ω and 8Ω by configuring dual 4Ω voice coils in series or parallel, supporting 300W RMS and 1200W peak power handling.
- Flexible Enclosure Compatibility: Designed for sealed, ported, and infinite-baffle installations, offering versatile system integration and optimized bass performance across different setups.
- Dynamic RGB Illumination System: Built-in red, green, and blue LEDs behind the grille provide customizable lighting effects with multiple color combinations including white, aqua, yellow, and pink.
- Marine-Grade LED Connectivity: Includes a 4-pin waterproof Deutsch DT Series connector and harness for secure LED installation, with compatibility for external RGB controllers (sold separately).
- Dual Terminal Connectivity Options: Features both standard quick-slide terminals and a sealed 2-pin Deutsch connector for flexible, corrosion-resistant wiring.
- Enhanced Cone Efficiency Technology: Utilizes VAST (Vertical Attach Surround Technique) to increase effective cone area, improving bass output without increasing overall frame size.
- Precision Acoustic Engineering: Klippel Verified design optimizes motor structure, suspension performance, and voice coil alignment for reduced distortion and improved sound accuracy.
- Corrosion-Resistant Construction: Built with stainless steel mounting hardware to withstand long-term exposure to saltwater and marine environments.
- Optimized Bass Performance Tuning: Engineered to deliver deep and controlled low-frequency response whether used in sealed, ported, or free-air configurations.
Specifications:
- Voice Coil Type: Dual Voice Coil
- Nominal Impedance (Ohms): 2-Ohm or 8-Ohm Switchable
- Size: 12"
- Power Handling (Watts RMS): 300 Watts RMS
- 1200 Watts PEAK
- Voice Coil Diameter: 2" (50 mm)
- Magnet Weight (oz): 39.75 oz. (1.13 Kg)
- Frequency Response: 20 Hz - 750 Hz
- Fs (Hz): 26
- Re (Ohms): 3.8
- Le (mH): 2.02
- Sd (cm2): 585.4
- Qms: 7.47
- Qes: 0.57
- Qts: 0.53
- Vas: 114.2
- SPL (dB @ 1w/1m): 92
- Xmax (mm): 6.0
- Woofer Displacement: 3.49 cu. ft. (0.12 Liters)
- Speaker Connector: Deutsch™
- Cutout Diameter: 10.85 in. (275.6 mm)
- Mounting Depth: 6.65 in. (169.1 mm)
- UPC: 780687353872
- Weight: 12
- Authorized Internet Dealer
Warranty: 2 Year(s) Warranty.
This item is accompanied by a manufacturer's warranty. If it is found to be defective, it may be returned to OnlineCarstereo.com for replacement within 2 Year(s) from the original date of purchase with proper return authorization.
