Rockford Fosgate M1D4-8B M1 8" DVC 4Ω Color Optix Marine Subwoofer - Black

Rockford Fosgate M1D4-8B M1 Series 8 Inch DVC 4-Ohm Color Optix Marine Subwoofer in Black

A marine grade 8 inch dual voice coil 4-ohm subwoofer in black with Color Optix RGB LED lighting, 150W RMS handling, and VersaSwitch impedance selection between 2-ohm and 8-ohm. Santoprene VAST surround, mineral-filled polypropylene cone, vented motor with nano-coated mesh screen, and integrated Deutsch/Amphenol plug-and-play connectors. Ultra-shallow 3.43 inch mounting depth suited to very space-constrained installations. IPX6 rated and ASTM B117 and G154 tested. Sold individually (1 each). Backed by a 2 year warranty.

Product Overview

The Rockford Fosgate M1D4-8B is an M1 series 8 inch dual voice coil (DVC) 4-ohm marine subwoofer in black, featuring Color Optix RGB LED illumination controllable via the PMX-RGB controller and RF Connect app (available on iOS and Android, sold separately). As the most compact subwoofer in the M1 Color Optix marine range, it is designed for installations where the 10 and 12 inch models cannot physically fit, offering a 7.10 inch cutout diameter and a shallow 3.43 inch mounting depth.

The VersaSwitch allows impedance to be changed between 2-ohm (parallel) and 8-ohm (series) by flipping a single switch, without any additional wiring. Integrated Deutsch/Amphenol connectors are moulded directly into the basket frame, providing error-proof plug-and-play connectivity for both the speaker signal and Color Optix RGB lighting. Conventional zinc nickel-plated marine grade brass spade terminals are also included as an alternative wiring option.

The cone is injection-moulded mineral-filled polypropylene with UV inhibitors, co-moulded with a Santoprene VAST surround. Rockford Fosgate's patented VAST technique increases the effective radiating cone area by up to 25%. A linear synthetic fiber blend spider provides consistent excursion control. The 1.5 inch (39mm) Kapton voice coil former is sized appropriately for the 8 inch driver. The vented motor design with a water-repelling nano-coated mesh screen allows heat dissipation at high output levels while protecting the motor from water ingress. The 100% UV stable ASA plastic frame and grille resist discolouration in marine environments.

Tested to ASTM B117 (500-hour salt/fog), ASTM G154 (500-hour accelerated UV), and ISO60068-2-64 vibration standards. Klippel Verified certification applied. Sold individually - one subwoofer per purchase.

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Features & Benefits

Most Compact M1 Marine Subwoofer - 8 Inch with 3.43 Inch Mounting Depth: The M1D4-8B is the smallest subwoofer in the M1 Color Optix marine range, with a 7.10 inch cutout diameter and only 3.43 inch mounting depth. It is purpose-built for vessels and compartments where the 10 and 12 inch M1 models cannot physically fit.

VersaSwitch - 2-Ohm or 8-Ohm Without Rewiring: The VersaSwitch allows the DVC 4-ohm voice coils to be configured to parallel (2-ohm) or series (8-ohm) by flipping a single switch, enabling flexible amplifier matching without additional wiring or soldering.

Color Optix RGB LED Lighting - App Controlled: Ultra-bright wide-angle RGB LEDs are protected by optically clear UV stable encapsulation, controllable via the PMX-RGB controller and RF Connect app on iOS and Android. The PMX-RGB controller is sold separately.

Integrated Deutsch/Amphenol Connectors - True Marine Ecosystem: Moulded in-frame Deutsch/Amphenol connectors combine speaker signal and Color Optix RGB lighting into a single error-proof plug-and-play connection. Zinc nickel-plated marine grade brass spade terminals are also included for standard wiring installations.

Santoprene VAST Surround - UV and Salt-Fog Resistant: The Santoprene VAST surround is co-moulded to the mineral-filled polypropylene cone and attaches vertically using Rockford Fosgate's patented VAST technique, increasing the effective radiating cone area by up to 25% for more bass output from the same 8 inch driver.

Vented Motor with Nano-Coated Water-Repelling Mesh Screen: The vented motor design allows heat to dissipate from the 1.5 inch (39mm) Kapton voice coil former at high output levels, while the nano-coated mesh screen prevents water from entering the motor assembly in spray-intensive marine environments.

ASTM and ISO Tested - Purpose-Built Marine Construction: Tested to ASTM B117 (500-hour salt/fog), ASTM G154 (500-hour accelerated UV), and ISO60068-2-64 vibration standards. IPX6 water intrusion rating confirms protection against powerful jets of water from any direction.

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Technical Specs

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Compatible With / Goes Well With

The M1D4-8B is suited to marine watercraft, pontoon boats, ski boats, and any vessel requiring the most compact Color Optix marine subwoofer option. Its 7.10 inch cutout and 3.43 inch mounting depth make it the choice when neither the 10 nor 12 inch M1 models will fit the available mounting position. The VersaSwitch enables pairing with amplifiers rated at 2-ohm or 8-ohm. Sold individually.

Goes Well With:

• PMX-RGB - Rockford Fosgate Color Optix RGB controller required to access full Color Optix lighting control and RF Connect app integration
• M2-500X1 - M2 series 500W mono marine amplifier - a practical power match for the M1D4-8B at 150W RMS
• M5-1000X1 - M5 series 1000W marine monoblock amplifier at 2-ohm or 8-ohm VersaSwitch settings for more headroom
• M5-1500X5 - M5 series 1500W 5-channel marine amplifier for full system builds pairing the M1D4-8B with marine full-range speakers
• M1D4-8 - White version of this subwoofer for colour-matched installations
• M1D4-10B - Larger M1 series 10 inch black DVC 4-ohm subwoofer for installations with more available space

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Frequently Asked Questions

How does the M1D4-8B compare to the larger M1 series subwoofers?

The M1D4-8B is the most compact subwoofer in the M1 Color Optix marine range, handling 150W RMS from an 8 inch driver with a 3.43 inch mounting depth and 7.10 inch cutout. The M1D4-10B handles 300W RMS from a 10 inch driver requiring a 4.23 inch mounting depth, and the M1D4-12B handles 300W RMS from a 12 inch driver requiring a 6.65 inch mounting depth. The 8 inch model delivers less output and bass extension than the larger options, but its compact format makes it the only viable choice in many space-constrained vessel locations.

What impedance settings does the VersaSwitch provide on the M1D4-8B?

The M1D4-8B uses DVC 4-ohm voice coils. The VersaSwitch configures the coils to parallel (2-ohm total) or series (8-ohm total) without any rewiring. Use the 2-ohm parallel setting when pairing with an amplifier rated for 2-ohm loads for maximum output, or the 8-ohm series setting for amplifiers better suited to a higher impedance load.

What amplifier power is recommended for the M1D4-8B?

The M1D4-8B handles 150W RMS at its DVC 4-ohm voice coil configuration. For best results, pair it with a marine mono amplifier rated between 75W and 150W RMS at 2-ohm (parallel) or 8-ohm (series) depending on your VersaSwitch setting. The M2-500X1 at 300W RMS at 2-ohm provides comfortable headroom without significantly overpowering the driver.

Is the M1D4-8B sold as a single unit or as a pair?

The M1D4-8B is sold individually - one subwoofer per purchase. Two units will need to be added to the order if a dual subwoofer installation is required.

Does the M1D4-8B come in a white version?

Yes. The white version is available as the M1D4-8, sharing the same specifications and construction.