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MTX Amplified ThunderForms
Custom-fit powered subwoofer for 1999-07 GMC/Chevrolet Extended Cab (Charcoal)
Our take on the MTX Amplified ThunderForms by Crutchfield's John Pollard
Crinkled french fries, discarded receipts, old gum wrappers you probably have everything in the hidden corners of your vehicle except great bass. But with custom ThunderForm enclosures, you can fill the nooks and crannies of your car, truck, or SUV with low tones that stand out.
MTX engineers evaluate the "sonic signatures" of top-selling vehicles so they can design ThunderForms as custom acoustic matches. With "rotational molding," MTX ensures that each ThunderForm fits and blends inconspicuously into your vehicle. They're made of high-density polyethylene resin to curb resonances and deliver bass that's tight, hard-hitting, and way down low.
This molded MTX ThunderForm comes loaded with two premium-quality 10" Terminator subwoofers modified especially for amplified Thunderforms, with a specially-designed amp that puts out 200 watts of power. It mounts under the rear seat on the driver side of 1999-up GM/Chevy Extended Cab models, and 1999-2002 GMC pickups (3-door and Extended Cab 4-door models). It's seamless and airtight, with the correct internal volume to yield optimum bass response from the subwoofers.
The ThunderForm bolts to the floor of the vehicle, with the woofers firing downwards. There is no loss of leg room and the factory jack kit is not disturbed. Hardware is included.
Well it fits very good and sound is more than my truck needs. I might have wanted more bass if i was twenty but i'm 53 and just wanted good clean full sound. I love how discreet it is under the rear seat. I think i would like to have seen better quality speakers but it works fine for now.
George, lake tahoe, Ca
What's in the Box:
- Amplified ThunderForm enclosure loaded with two 10" Terminator subwoofers
- Two 20 amp fuses (1 in-line/1 installed in the ThunderForm)
- Wiring harness (20' power lead/3' ground lead and 3' remote turn-on lead)
- Speaker-level to RCA harness
- Electronic Bass Control (wired remote) with attached cable
- Mounting hardware
- Installation instructions
- custom-fit powered subwoofer
- enclosure fits under rear seats
- two Terminator 10" subwoofers
- built-in 200-watt RMS amplifier
- high-density polyethylene enclosure
- variable low-pass filter (50-150 Hz at 12 dB per octave)
- preamp- and speaker-level inputs
- warranty: 2 years
- Our 60-day money-back guarantee
MTX Amplified ThunderForms Reviews
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Vehicle-Specific Custom Enclosure: This MTX ThunderForm enclosure is specifically designed to fit select full size GM extra cab pickups. Please refer to the Crutchfield Car Selector to confirm fit for your vehicle.
Enclosure: The ThunderForm enclosure is made of molded high-density polyethylene resin, which dampens resonance and is rigid enough to resist flexing. The color of the enclosure matches factory GM colors. It is an acoustic suspension (sealed) chamber.
Mounting Location: This enclosure is designed and molded to mount under the rear seat. The jack does not need to be relocated. Note: The provided dimensions are taken at the widest points of the enclosure. Keep in mind that these enclosures are custom made to fit in this particular vehicle, so the enclosure will fit properly in only one specific location.
10" Terminator Subwoofers: This enclosure comes loaded with two 10" MTX Terminator subwoofers. The woofers have an unusual impedance, specifically designed for the built-in amp, and cannot be replaced with standard MTX models.
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.
Electronic Bass Control (EBC): The EBC is a wired remote and allows you to adjust the bass level from anywhere in the vehicle. Installing the EBC is optional.
Low-pass Crossover: The low-pass crossover point is adjustable from 50 to 150 Hz for a seamless transition between the output of this unit and that of the other speakers in the vehicle.
- Gain Control: rotary control; set the gain of the amplifier is match the input
- Crossover Control: rotary control; adjust the crossover from 50 to 150 Hz
Auto Turn-On Feature: When 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 preamp level inputs are used, connecting the remote turn-on lead is required.
Tools Required: The manual provides this list of required tools:
- Powered Screwdriver
- #2 Phillips Head Bit
- Wire Cutters
- T50 Torx
- 5/16" Wrench
- Terminal Crimper
- 6" Bit Holder Extension
- 7mm Nut Driver
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1 question already asked
I forwarded your question to an Advisor and they responded with the following: The range is 29-150 Hz. If you would like to discuss further you can contact an Advisor directly by phone (1-800-324-9695) or online chat. [ Krissy May 12, 2015 ] Staff