Why Choose Crutchfield?
Great gear and expert advice
Our experts help you pick the ideal gear for your needs.Meet our advisors
Free tech support for the life of your gear.Read about our one-on-one expert help
You may return items that are complete and like new for any reason within 60 days.See the details of our return policy
Earn one point for every dollar you spend and use those points to save on future purchases.Get full details on Crutchfield Rewards
Deep discounts on car installation gear
We offer vehicle-specific installation instructions, dash kits, wiring harnesses, and speaker accessories at deeply discounted prices with car stereo and speaker purchases. Available for most vehicles.Learn more
Trusted since 1974
Our customers have trusted us with their business, and they’ve helped us win awards for our service.Check out our most recent awards
The manufacturer’s warranty always applies.See more details
MTX Amplified Thunderforms
Custom-fit powered subwoofer for
2004-up Ford F-150 regular cab (Tan)
Our take on the MTX Amplified Thunderforms by Crutchfield's Ken Nail
Crinkled french fries, discarded receipts, old gum wrappers you probably have everything in the hidden corners of your vehicle except great bass. ThunderForm enclosures fill the nooks and crannies of your vehicle with low tones that stand out, but their factory look blends right in.
MTX engineers evaluate the "sonic signatures" of top-selling vehicles so they can design ThunderForms as custom acoustic matches. Each ThunderForm fits and blends inconspicuously into your vehicle, so you get great bass without losing any space. They're made of high-density polyethylene resin to curb resonances they deliver bass that's tight, hard-hitting, and way down low. The airtight enclosure provides the correct internal volume to yield optimum bass response.
This amplified ThunderForm comes equipped with a cool-running 200-watt amp that's custom designed to provide optimal power without straining your vehicle's electrical system. MTX's Electronic Bass Control (EBC) lets you adjust the bass level from the driver's seat. A variety of inputs allow easy integration into your vehicle's sound system, and the included 20' power harness simplifies supplying power to the amp.
Fits perfectly in my truck, looks great, sounds awesome. Couldnt be happier. I strongly recommend thunderforms if you have a regular cab F-150.
Rock, Torrance, CA
What's in the Box:
- Tan amplified ThunderForm enclosure loaded with two 12" Thunder4500 subwoofers and a 20A ATC fuse
- Wiring harness (20' power lead/3' ground lead and 3' remote turn-on lead)
- 1 Fuse holder with attached wire loop
- One 20A ATC fuse
- One 0.202" crimp-on ring
- One 0.414" crimp-on ring
- 1 Yellow butt connector
- Two 5' RCA high-level input wires (each wire has an RCA connector on one end and tinned wire on the other end)
- External bass control with attached 17.5' cable (has a right-angle minijack stereo connector)
- 1 Plastic knob (for the external bass control)
- 1 Metal mounting bracket
- Two 3/4" self-tapping screws
- 1 Medium flat washer
- 2 Small flat washers
- 2 Lock washers
- 1 Hex nut
- One 3-3/4" cable tie
- 1 External bass control sticker
- 2 Large flat washers
- 2 Large self-tapping screws
- custom-fit powered subwoofer
- enclosure fits behind seat
- two 12" Terminator subwoofers
- built-in 200-watt RMS Class-D amplifier
- high-density polyethylene enclosure
- variable low-pass filter (50-150 Hz at 12 dB per octave)
- preamp- and speaker-level inputs
- 20' power harness included
- warranty: 2 years
- Our 60-day money-back guarantee
MTX Amplified Thunderforms Reviews
Average Customer Review(s):
Thanks for submitting your review
Class D Amplifier: The enclosure contains a built-in 200-watt Class D (digital) amplifier that allows RCA or speaker-level input. The amplifier is highly efficient and designed specifically for use with the subwoofers in the enclosure.
Built-in Low-pass Filter: The low-pass filter frequency can be varied from 50 to 150 Hz for a seamless transition between the output of this unit and that of the other speakers in the vehicle.
Auto Turn-On Feature for Speaker Level Input: When the using a speaker level input signal (with the included speaker level to RCA adapter), the subwoofer's built-in amplifier will automatically turn on and off with the radio.
Note: The auto turn-on feature does not operate when a preamp level signal is used; the remote turn-on lead is necessary.
External Bass Control: The external bass control allows you to adjust the bass level from anywhere in the vehicle.
Thunder4500 Woofers: The enclosure comes loaded with two 12" Thunder4500 dual voice coil woofers.
Note: The woofers have an unusual impedance, specifically designed with the amp, and cannot be replaced with standard MTX models.
Carbon-filled Polypropylene Cones: Each woofer cone is made of carbon-filled polypropylene. Carbon adds strength and heat resistance to polypropylene; the result is reduced distortion and improved reliability. In addition, the cone is also very resistant to environmental extremes. Each woofer uses a polyether foam surround.
Asymmetrical Linear Drive System (ALDS): The Asymmetrical Linear Drive System consists of a flat, progressive spider that improves suspension and an extended vented pole piece that smoothes out the cone's linear motion. The result is high output and low distortion.
Spider Plateau Venting: Heat from the voice coil is vented through metal-mesh covered vents that surround the back of the spider.
Voice Coils: The voice coils are wound on high-temperature formers to promote high power handling.
Strontium Ferrite Magnets: The strontium ferrite magnets yield highly efficient speakers.
Molded Enclosure: The molded, high-density polyethylene resin enclosure resists flexing and dampens resonance.
- Gain Control: rotary control that allows you to set the gain of the amplifier
- Crossover Control: rotary control that allows you to adjust the crossover from 50 to 150 Hz
- Input: left and right RCA jacks; these jacks allow speaker-level input when the supplied RCA high-level input wires are connected
- EBC: mini-jack for use with supplied external bass control
- Harness: 3-pin jack for use with supplied wiring harness
- Fuse: installed 20A ATC fuse
Our Product Research Team
At Crutchfield, you'll get detailed, accurate information that's hard to find elsewhere. That's because we have our own in-house Product Research team. They verify what’s in the box, check the owner's manual, and record dimensions, features and specs. We stay on top of new products and technologies to help people make informed choices.