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MTX Amplified ThunderForms

Custom-fit powered subwoofer for 2004-up Chevy Colorado or GMC Canyon Crew Cab (Tan)

3 Reviews

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Item # 236COLTAFP

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Our take on the MTX Amplified ThunderForms

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.

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.

Built-in 200-watt amp and 10" sub
This amplified ThunderForm comes equipped with a cool-running 200-watt amp that's custom designed to provide optimal power to its 10" FPR subwoofer 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.

Made for your vehicle
This enclosure installs under the rear passenger seat in your 2004-up Chevrolet Colorado or GMC Canyon Crew Cab, extending out in front of the cup holder. Please check with us before purchasing by using the vehicle selector on our site, or calling an Advisor at 1-888-955-6000 to verify fit information.

Product Highlights:

  • custom-fit powered subwoofer
  • enclosure fits under the rear seat and in front of the cup holder
  • one down-firing 10" FPR subwoofer
  • 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

What's in the Box:

  • Tan amplified ThunderForm enclosure loaded with one 10" FPR subwoofer 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
  • Manual

MTX Amplified ThunderForms Reviews

Average Customer Review(s):

(3 Reviews)

Looks Great, don't work.

Brian from Trenton, MI on 5/1/2016

2010 Chevrolet Colorado
Crutchfield Customer Review (What's this?)

I was looking for something to put in my truck with out giving up my back seat. It sat on my shelf until I finally got around to installing it 6 months ago. Sounded great for what it is. Was not expecting a great booming sound, like that from my full size box in my other SUV. But it added bass to my music. Color match was right on, and looked like it came from the factory the way it fit. Last week it stopped working, amp quit working. I did have it installed professional. Really disappointed.



MTX Thunderform for Cevy Colorado

Sam T. from Renton WA on 12/11/2014

2009 Chevrolet Colorado
Crutchfield Customer Review (What's this?)

Crisp sound, easy install and the bass thumps!

Pros: Crisp sound and easy install. The product came fast in the mail! Very happy

Cons: None that I can come up with


Gregory from Crimora, Va on 9/5/2014

Crutchfield Customer Review (What's this?)

I upgraded the factory system to a sony dvd with polk db's all around in my 05 colorado Crew Cab. Components in the front and 2 ways in the rear. Still little to no bass. System was a lot louder though. you could actually hear it with the windows down now. Then I added the amplified Thunderform under the rear seat. It is a 1000% improvement. Good low bass, and rather intense. You may not win any crank it up contest but its well worth the money. Install was easy too.

Pros: Sounds Great, Well made, Plenty loud for my needs, Install was easy even though I had to pull out the rear seat to do so.

Cons: Plastic power connector is fairly cheesy, Provided rca cables are very cheap. I opted to use a set of rockford cables I already had. The big thing for me was that the color did not quite match. I have dark pewter and the charcoal of the tform Did not match by a few shades but still ok. This is the only reason i did not give it 5 stars.


Hands-on research

Product Research


Molded Enclosure: The molded, high-density polyethylene resin enclosure resists flexing and dampens resonance.

FPR Woofer: This enclosure comes loaded with one 10" FPR woofer. The woofer has an unusual impedance, specifically designed with the amp, and cannot be replaced with a standard MTX model.

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 subwoofer 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: When the speaker level inputs are used, the system will automatically turn on and off with the radio.

Note: The auto turn-on feature does not operate when the preamp level inputs are used, unless the remote turn-on lead is connected.

External Bass Control: The external bass control allows you to adjust the bass level from anywhere in the vehicle.

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