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Rockford Fosgate R2SD4-12
Prime R2 Series 12" shallow subwoofer with dual 4-ohm voice coils
Item # 575R2SD412 | MFR # R2SD4-12
This item is no longer available.
Our take on the Rockford Fosgate R2SD4-12 by Crutchfield's Jo Greene
Rockford Fosgate's Prime R2 shallow-mount subs deliver satisfying bass even in smaller cars where space is tight. A special elevated motor structure lets these low-profile subs work in extremely compact enclosures, while still handling plenty of power.
The R2SD4-12 sub features a 12" mica-injected polypropylene cone that works with a high-density poly-foam surround to punch out fat, deep notes. This shallow-mount workhorse will handle up to 250 watts RMS, with a mounting depth of only 3-5/8". Rockford Fosgate stitches the tinsel leads that carry the signal to the voice coils directly into the cone, so they'll hang tough through heavy use. The stamped solid-steel frame offers the same venting found in standard-mount Rockford Fosgate subs to keep this sub running cool.
Dual 4-ohm voice coils allow you to wire this sub for 2- or 8-ohm impedance, giving you more flexibility in setting up your system. Rockford Fosgate optimizes this Prime sub for both sealed and ported enclosures so you can choose the type of bass you want in your ride.
To drive this single subwoofer, we recommend a mono amplifier rated between 200 and 375 watts RMS at 2 ohms. For more information, please refer to our article on How to Match Subwoofers and Amplifiers.
great sub at a great price the sound is amazing and I cant say enough about crutchfield, ordering was easy, shipped and delivered quickly i'm only ordering from you guys from now on thanks!
ray l, Florida
What's in the Box:
- One shallow-mount 12" Dual 4-ohm voice coil woofer
- Eight 1-1/8" Self-tapping screws
- 4mm Allen bit
- Installation and Operation manual (English/ French/ Spanish/ German)
- 12" shallow-mount subwoofer with dual 4-ohm voice coils
- mica-injected polypropylene woofer cone with poly-foam surround
- stamped solid-steel frame
- power range: 100-250 watts RMS (500 watts peak power)
- frequency response: 29-250 Hz
- sensitivity: 85 dB
- top-mount depth: 3-5/8"
- sealed box volume: 0.9 cubic feet
- ported box volume: 1.79 cubic feet
- warranty: 1 year
- Our 60-day money-back guarantee
Rockford Fosgate R2SD4-12 Reviews
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Features and Specs
|Impedance||2 ohms or 8 ohms|
|Cone Material||Mica injected Poly|
|Ideal Sealed Box Volume (cubic feet)||0.9|
|Ideal Ported Box Volume (cubic feet)||1.79|
|Port diameter (inches)||4|
|Port length (inches)||11.8|
|Dual Voice Coil||Yes|
85 dB at 1 watt
|Frequency Response||29 - 250 Hz|
|RMS Power Range (Watts)||100-250|
|Peak Power Handling (Watts)||500|
|Top Mount Depth (inches)||3 5/8|
|Bottom Mount Depth (inches)||N/A|
|Cutout Diameter or Length (inches)||11 1/8|
|Parts Warranty||1 Year|
|Labor Warranty||1 Year|
Shallow Mount Design: The Rockford Fosgate Prime R2 Shallow Subwoofer is designed and engineered with a much smaller motor assembly which reduces the overall depth of the woofer allowing it to fit in shallower enclosures and tighter locations of your vehicle.
Dual 4-ohm Voice Coils: This woofer features dual 4-ohm voice coils to offer wiring flexibility. When the voice coils are wired in parallel the woofer presents a 2-ohm mono load, when wired in series it presents an 8-ohm mono load.
Spring Post Assembly: The woofer features compression input terminals with attached 16-gauge stitched tinsel lead wires. The nickel plated spring posts will accept pin connectors, single banana plugs, and bare wire up to 12-gauge.
Sealed Box Volume: Rockford Fosgate recommends a sealed enclosure with an optimum internal volume of 0.9 cubic feet (from 0.75 to 1.25 cubic feet is acceptable). Sealed enclosures provide the most control over a woofer, will handle a lot of power, and provide accurate sonic reproduction, making them suitable to all types of music.
Vented Box Volume: Rockford Fosgate recommends a vented enclosure with an internal volume of 1.79 cubic feet using a 4" diameter x 11.8" long port tube; this yields a tuning frequency of 40 Hz. Ported (or vented) enclosures typically provide better overall efficiency than sealed so they are suitable for use with smaller amplifiers, giving you more bass output from less power. However, this efficiency comes at the expense of very low frequency output (below 35 Hz).
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Why did you buy this?
Needed a reasonably priced speaker [ Gerold May 17, 2016 ]
I needed a shallow sub, since I drive a former police car, and have a full size spare tire, sitting in the dead center of my trunk. [ A Apr 24, 2016 ]
4 questions already asked
Thanks for your question. For information on selecting the best amp for your subs I would recommend reaching out to an Advisor by phone (1-800-324-9695) or online chat. They will be able to help determine the differences between the amp models and help you make the best choice for your system. [ Krissy Jan 04, 2016 ] Staff
I forwarded your question to an Advisor and they responded with the following: I'm not sure exactly what the value would be on a used sub but I personally think that is a good price for two. If you would like to discuss further you can contact an Advisor directly by phone (1-800-324-9695) or online chat. [ Krissy Jan 01, 2015 ] Staff
Thanks for your question. For information on selecting the best amp for your subs I would recommend reaching out to an Advisor by phone (1-800-324-9695) or online chat. They will be able to help determine the differences between the amp models and help you make the best choice for your system. [ Krissy Sep 05, 2014 ] Staff
I forwarded your question to an Advisor and they responded with the following: You can use those in either a sealed or ported box. A sealed box will need a volume around 0.9 and a ported 1.79. If you would like to discuss further you can contact an Advisor directly by phone (1-800-324-9695) or online chat. [ Krissy May 20, 2014 ] Staff