SKU: S65BOX500
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Single 12" Square Subwoofer, Amplifier, Wiring Kit and Enclosure Package

Built for SPL

S65 Series square subwoofers are built to deliver exceptional SPL and the most bass for your buck.

The S6512-44 is a 12" dual voice coil, 400 watt, 4 ohm square car audio subwoofer built on the MTX tradition of getting more than expected.

MTX THUNDER500.1 is designed to work with an assortment of subwoofers and is capable of delivering up to 500 watts RMS power  in an incredibly small package.

This monster amp features a high efficiency class D topology. This type of circuit is preferred for driving subwoofers due to its ability to minimize power loss to heat when you rock all night long.


Wire, fuse, fuse holder and fittings required to connect amplifier to electrical system.

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The Perfect Package

This package includes everything bass lovers need to add killer bass to their vehicle's sound system. Featuring the feature rich, patented S65 square 12" subwoofer, the THUNDER500.1 class D high efficiency amplifier, a vented BassSlammer enclosure, and 4-AWG wiring from StreetWires, this package has it all. Each piece in this package has been specifically selected to maximize the performance of each of the other parts ensuring that you get More Than Xpected!

Patented Surround Geometry

Delivers increased Xmax resulting in higher SPL and less distortion.

Progressive Suspension

Controls excursion at high power lowering 3rd order distortion.

Radial Ribbed T-Yoke

Dissipates heat and decreases distortion.


The S65 Series

The S65 Series is designed for enthusiasts that want to add extreme bass to their system. With more surface area than a standard round subwoofer and patented corner geometry that increases Xmax, the S6512-44 square subwoofer delivers exceptional volume displacement that translates to exceptional SPL. The woofer features dual layer cooling technology with Spider Plateau Venting technology that utilizes the subs movement to cool it as it plays and a radial ribbed t-yoke dissipates heat away from the voice coil through the back plate, so it doesn't overheat even under intense use. 

S65 Series Key Features

  • Patented Surround Geometry US Patent #7,275,620
  • Surround Allows for Increased Xmax Resulting In Higher SPL and Volume Displacement
  • Spider Plateau Venting Mechanically Targets Cool Air at the Voice Coil
  • Radial Ribbed T-Yoke Dissipates Heat and Decreases Distortion
  • 2.0" High Temperature Voice Coil

S65 Series Spider Plateau Venting

This square subwoofer also incorporates Spider Plateau Venting which is a mechanical cooling process that targets cool air at the voice coil and a radial ribbed t-yoke that acts as a heat sink effectively managing the subwoofer temperature for long term performance.

Surface Mount Design

Resists vibration for reliability under the harshest conditions

Small Footprint

Easy install in any vehicle, anywhere

Variable Crossover

Tune a wide range of speakers to perfection

Extruded Heatsink

Keeps the amplifier cool without a fan

High Power High Value

The THUNDER500.1 is a high powered subwoofer amplifier capable of delivering up to 500 watts RMS power at 2Ω. Additionally, the unit is designed to be installed in almost any vehicle due to its small chassis size.

THUNDER 500.1 Key Features

  • Mono block amp for subwoofer(s)
  • Small Footprint
  • Extruded Aluminum Heat Sink
  • Surface Mount PCB Design
  • Variable Crossovers


Technologically Advanced

The THUNDER500.1 features surface mount technology. This design uses smaller more efficient parts that adhere to the circuit board much better than traditional through hole designs making it extremely vibration resistant.

Dimensions & Details


  • Recommended Amp Power (RMS): 250 - 500
  • Impedance: Dual 4Ω
  • Frequency Response: 23Hz - 130Hz
  • Sensitivity: 86.7dB (1W/1m)
  • Volume Displacement (cu in): 68.47
  • Voice Coil: 2" (5.08 cm)
  • Mounting Depth: 6.9375" (17.62cm)
  • Cut Out Diameter: 11.125" (28.26cm)


  • Owners Manual - MTX004553 THUNDER Series Owners Manual (32 pages)
  • Owners Manual - THUNDER500.1 Owners Manual (32 pages)
  • Installation Sheet - T/S Parameters Tech Data Sheet (2 pages)

Returns & Warranty

30-Day Money-Back Guarantee

At MTX Audio, we are serious about sound®. Therefore, if you are not "blown away" with your purchase, for any reason, you can return any items purchased directly from that are complete and like new within 30 days. Products purchased from authorized MTX retailers must be returned through that same retailer. Products purchased through non-authorized MTX retailers may not be returned.

About Returns
Warranty Information

MTX products purchased in the USA from an authorized MTX dealer are guaranteed against defects in material and workmanship for the period of time specified below, the warranty period begins the day the product is purchased by the end user. This warranty is limited to the original retail purchaser of product and extends only to products purchased from authorized MTX resellers. Product found to be defective during that period will be repaired or replaced by MTX at no charge.

About Our Warranty


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