Want big bass? Look at our Subwoofers

Designed to pump out plenty of raw power for your subs, an MTX Thunder subwoofer amplifier provides you with the features you need to drive your system efficiently. MTX built the Thunder amps to work hard — Xtant Technologies Cooling (XTC) forces air from an internal fan over all of the important components, so the amp will stay cool when the going gets tough.

And since it's not all about power, MTX's Prizm EFX feature allows you to choose the lighting display color of the amp — pick from infinite shades of red, green, or blue — and you can set it to pulse with the music. Your system, your look, and great sound.

The Thunder4501 amplifier pushes out a solid 250 watts to a single 4-ohm subwoofer, while laying down 500 watts to two subs. A variable low-pass filter maximizes system performance by tailoring your sub's output to match its enclosure and your vehicle. A switchable bass boost gives you some extra bump when you need it.

StreetWires-designed connections transfer power with ultimate efficiency, and they're laid out on one side of the amp so wiring is easier than ever. The amp's controls are top-mounted and readily accessible. Thanks to MTX's rigorous quality control and advanced technologies, you always get quality performance with a Thunder amp onboard.

Product Highlights:

  • mono car subwoofer amplifier (Class D)
  • 250 watts RMS x 1 at 4 ohms (500 watts x 1 at 2 ohms)
  • fan cooling with XTC thermal regulation technology
  • Prizm EFX customizable lighting accents
  • variable remote bass boost (0-18 dB at 40 Hz)
  • variable low-pass filter (40-200 Hz at 24 dB per octave)
  • MOSFET power supply and output stage
  • CEA-2006 compliant
  • speaker-level inputs with Smart Engage
  • 4-gauge power and ground leads recommended — wiring and hardware not included with amplifier
  • fuse rating: 20A x 3
  • 16-3/4"W x 2-5/8"H x 10"D
  • warranty: 3 years
  • Our 60-day money-back guarantee

My system has plenty of power. Who needs an amp?

You might think you don't need an amp because you have a 400-watt system in your car, or because your new stereo puts out 50 watts a channel. But those are peak wattage ratings, which may boil down to 15 or 20 watts per channel, using the more realistic RMS rating. An amp sends your speakers the power they need to deliver your music with clarity and impact, whether you're using factory speakers or high-performance components. And low-frequency reproduction requires lots of power, so an amp is an absolute must if you're adding a sub to your system.

Hands-on research

What's in the box?

Download owner's manual

  • Mono amplifier with three 20A ATC fuses inserted into the chassis
  • External Bass Control with attached 19.5' cable (terminated with a minijack stereo connector)
  • 1 External Bass Control mounting bracket
  • 1 Self-adhesive "Min/Max" label
  • 1 Knob (for the External Bass Control)
  • 2 Self-tapping screws
  • 1 Large flat washer
  • 2 Small flat washers
  • 2 Lock washers
  • 1 Hex nut
  • One 3.75" wire tie
  • 9.75' Green high-level adapter cable (has an RCA connector on one end and tinned wire on the other end)
  • 9.75' Violet high-level adapter cable (has an RCA connector on one end and tinned wire on the other end)
  • 1 Allen wrench
  • 2 Plastic terminal covers
  • 1 "MTX Audio Motorsports" sticker
  • One 7" x 2" "Streetwires - Connected To The Streets" sticker
  • Instructions
  • Thunder Amplifier Dyno Certificate

Product Research

Inputs and Outputs Notes


Prizm EFX: With the MTX Prizm EFX, you can adjust the color of the display to match your vehicle interior. The display color can be set to red, green, blue, or any color in between. If desired, you can switch Prizm EFX lighting to "pulsate" with the beat of music.

Xtant Technologies Cooling (XTC): The Xtant Technologies Cooling (XTC) thermal-regulated, turbo-charged intercooler supplies fan forced cool air evenly and constantly through tightly packed, bonded fins. Fan speed is continuously variable and controlled by amplifier's output load, temperature of heatsink, and transformers. Exhaust of internal heatsink is strategically positioned to cool transformers to maintain maximum performance at all volumes.

Adaptive Class D Technology: While typical Class D amps tend to generate high frequency energy that must be filtered to prevent harmonic interference in the FM radio frequency range, Adaptive Class D Technology directs the amp's switching energy away from FM radio ranges as the amp's load and output increases. This improves the amp's overall signal-to-noise ratio and eliminates interference generated by more common Class D amps.

Smart-Engage: When using the speaker-level input, the amp automatically turns on when it senses signal from the head unit, eliminating the need for a remote turn-on connection. In many cases, this feature will allow you to install the amplifier without removing your radio.

External Bass Control: The External Bass Control lets you adjust the output level of the amplifier from anywhere in the vehicle. When attached to the mounting bracket, the External Bass Control has the following dimensions: W=1.602", H=0.979", D=2.578" (including the knob).

Bass Boost: For added low frequency performance, this amplifier has a 0 to +18 dB variable bass boost centered at 40 Hz.

Variable Low-Pass Filter: The internal low-pass filter can be adjusted from 40 to 200 Hz, and has a slope of 24 dB per octave.

Bi-level Inputs: The RCA inputs will accept both speaker-level and line-level signals. To accept speaker-level input, you must use the supplied high-level adapter cables.

Capacitor Terminals: This amp provides power and ground connections for an optional capacitor.

StreetWires Connectors: This amp features StreetWires connectors for efficient current and maximum voltage transfer.

Input Sensitivity: The input sensitivity switch can be set to x1 (line-level input) or x10 (speaker-level input). When set to x1, the input sensitivity can be adjusted from 100mV - 1V. When set to x10, the input sensitivity can be adjusted from 1V - 10V.

Performance Certificate: MTX tests each amplifier, and the technician records the "actual" power output on the Thunder Amplifier Dyno Certificate included with each amp. The amp must meet or exceed the rated specification in order to leave the factory.

Inputs and Outputs Notes

Set-screw Terminals: The power and ground set-screw terminals will accept up to 4-gauge wire. The remote turn-on, capacitor, and speaker set-screw terminals will accept up to 8-gauge wire.

RCA Inputs: The RCA inputs will accept both speaker-level and line-level signals. To accept speaker-level input, you must use the supplied high-level adapter cables.

Remote Gain: This minijack allows you to connect the supplied External Bass Control.

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 open the box, verify contents, 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.

MTX Thunder4501 Reviews

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MTX Thunder4501

Written By c~blaze, rock island tn on Monday, August 06, 2007

i upgraded from the kenwood 1800 watt maxx mono amp...i love this mtx amp.hits hard,dependable to.never over heated it and i keep it above its 500 rms most the time

Get everything you’ll need to enjoy your new MTX Thunder4501

Bring the music from your amp to your speakers.
Patch cables take the music from your stereo to the amplifier. Most amp wiring kits don't include them.
Helps protect your car's charging system and improves power handling. Required power and ground wires not included with cap.
The right tools will make the installation easier.
Have your new amplifier put in by a qualified professional in your area.
T-Spec 12-gauge Speaker Wire

T-Spec 12-gauge Speaker Wire

Black/white jacket — priced per foot

Item #: 120SW12WB1


T-Spec 2-Channel RCA Patch Cables

T-Spec 2-Channel RCA Patch Cables

Available in 7 different lengths (17-foot)

Item #: 120RCA172


Add to Cart
EFX 2-Channel RCA Patch Cables

EFX 2-Channel RCA Patch Cables

Reference Series Multi-Core RCA patch cables — available in 5 different lengths (17-foot)

Item #: 142RR17

Add to Cart
T-Spec Capacitor

T-Spec Capacitor

1.5-farad capacitor with red LCD meter

Item #: 12015DDC


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S&G Tool Aid 87650

S&G Tool Aid 87650

Door Trim and Panel Removal Tool

Item #: 18187650


Skewdriver Pro SPK4042

Skewdriver Pro SPK4042

Ratcheting straight and offset screwdriver set with 40 bits (Skewdriver Pro with ratchet handle, pictured)

Item #: 180SPK4042


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Metra Crimp Tool and Connectors

Metra Crimp Tool and Connectors

Package contains crimp tool and over 150 pieces

Item #: 120CRIMPKT


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S&G Wire Cutter/Stripper Tool

S&G Wire Cutter/Stripper Tool

Cuts and strips 12- to 22-gauge wire

Item #: 18119100


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Install Bay IB35400

Install Bay IB35400

Premium door panel and trim tool

Item #: 12035400

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Install Bay 3320

Install Bay 3320

Auto-ranging digital multimeter

Item #: 1203320

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InstallCard: Amp or Equalizer

InstallCard: Amp or Equalizer

Prepaid professional amplifier or EQ installation

Item #: 597421003


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