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Upgrade your power for better sound

You'll add a big upgrade to your listening pleasure when you put an MTX TD75.4 4-channel amp in your car. This compact amp will fit almost anywhere, driving each of your front and rear speakers with 75 watts RMS of detail-enhancing musical power. Install a nice set of speakers, and you'll hear sounds you've never heard before, even in your favorite songs.


You can also put this amp into 2-channel mode to drive two subwoofers with 200 watts RMS per channel. In 3-channel mode, you can run some nice components up front with two channels while running a sub off the third channel.

Advanced tone control

The crossover filters on the front and rear channels allow you to adjust the sound to your setup. The front channels use a variable high-pass filter to keep the bass away from your full-range speakers, so they play cleanly. The variable rear crossover can be set to high- or low-pass depending on whether you're running a subwoofer or full-range speakers on the rear amp channels. It also features a very wide range of crossover points, that'll be useful for tuning midrange and midbass speakers.

TD75.4 control panel

Product Highlights:

  • 4-channel car amplifier
  • 75 watts RMS x 4 at 4 ohms (100 watts RMS x 4 at 2 ohms)
  • 200 watts RMS x 2 bridged at 4 ohms (4-ohm stable in bridged mode)
  • frequency response: 10-25,000 Hz
  • Class AB amp technology
  • variable high-pass filter on front channels (10-200 Hz, 12 dB/octave)
  • variable high- and low-pass filters on rear channels (50-750 Hz, 12 dB/octave)
  • preamp inputs
  • 8-gauge power and ground leads and a 60-amp fuse recommended — wiring and hardware not included with amplifier
  • no onboard fuses — when installing multiple amps in a system, an additional 60-amp in-line fuse between the distribution block and the amplifier is recommended
  • 12-7/8"W x 2-3/16"H x 5-9/16"D
  • warranty: 5 years (free repair or replacement for 2 years; prorated replacement for years 3 through 5)
  • 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.

MTX TD75.4 Reviews

Average Customer Review:

7 Reviews

Great amp!

Written by: PNWHatch from Kingston, WA on February 9, 2014

Crutchfield Customer Review (What's this?)

An easy install; I bolted this amp to the underside of the front passenger seat. It works great in my super cab F-250 and the sound is awesome.

Pros: Small enough to fit under the seat, & having tabs to bolt it down is also a huge plus. Instructions are easy for those who may not have a ton of experience with installation. The amp works great, bang for the buck!

Cons: I've none to mention.

Excellent amp for the money

Written by: Phil from Charleston, SC on January 22, 2014

Crutchfield Customer Review (What's this?)

I bought this amp to breathe some life into my 1989 S10 Blazer's stereo after living with an anemic head unit for years. I couldn't believe the price, but bought it anyway as it was well-reviewed and I could always return it. 2 days later it's in my hands, and I have to say it's a perfect fit for under the driver's seat to run all 4 factory speakers (and possibly future kickpanel seperates). This amp performs better than I had any right to think it would. Couldn't be happier!

Pros: performance, price, size, quick shipment.

Cons: none

MTX TD75.4

Written by: Steve K. from Lexington NC on January 13, 2014

Crutchfield Customer Review (What's this?)

Custom Autosounds Radio have sony 4-way xs-r5743 rear Sony XS-GT1638F 6-1/2" 3-way in front sounds great

Pros: eazy to install , runs cool, small unit takes up little space

Cons: none so far


Written by: Sam from Myrtle beach sc on December 17, 2013

Crutchfield Customer Review (What's this?)

I got this for my son's Chevy 1500 regular cab. There is not much room behind the seat but I mad a custom sealed box with two 10" kickers. I was worried when I opened the box and saw how small the amp was. I was thinking I would have to get a different one so I hooked it up for a test. I was very impressed. It makes the 10's hit hard and sounds good. Well worth the price.

Pros: Good price, small size

Cons: None yet

MTX TD75.4

Written by: DM from North Chesterfield, VA on December 14, 2013

Crutchfield Customer Review (What's this?)

Used this in an '84 El Camino with a Retro Sounds stereo and MTX 6x9 Thunderdome 100W speakers. Great sound full deep bass, crisp clear mids and highs.



MTX TD75.4

Written by: Tomas from Oxford, NC on December 7, 2013

Crutchfield Customer Review (What's this?)

Love it pushing four 6×8 component speakers

Pros: Love it mtx is always a good product


Great little amp

Written by: MPohio from Central, Ohio on December 5, 2013

Crutchfield Customer Review (What's this?)

Picked this up for my door speakers(infinity Kappas) and to compliment my sub amp(MTX thunder500.1). Very easy to install, brings my door speakers to life(I can now actually hear bass out of them). I like the fact that the rear channels have a seperate Freq control knob, besides a gain. This allows me to filter out lower bass, and bring out the vocals. It is quite small compared to others, which helped fit it in under my rear seats in my F150.

Pros: cool running, small footprint, brings my speakers to life, seperate freq control for my rears

Cons: Seriously, none found!!

Hands-on research

What's in the box?

Download owner's manual

  • 4-Channel amplifier
  • Four 1/2" Self-tapping screws
  • Owner's manual (English/ Spanish/ Portuguese/ French)
  • Fuse and wiring kit note

Product Research



2-Ohm Stable: The MTX TD75.4 is capable of handling load impedances down to 2-ohms in stereo; the amplifier is rated at 75 watts RMS x 4 channels into 4-ohms and 100 watts RMS x 4 channels into 2-ohms.

Bridgeable: The front and rear sections of the amp are independently bridgeable; the bridged output is 200 watts x 2 channels at 4-ohms (or 200 watts x 1 and 75 watts x 2 if only one half of the amp is bridged).

THD: The Total Harmonic Distortion isn't given at the rated power output, therefore it isn't listed in the specifications table. The manual does list THD as <0.05% at 30% of rated power (22.5 watts per channel) into a 4-ohm load.

Protection Circuits: The TD75.4 provides protection against over heating, output short-circuit, and over/under power supply voltage.

Gain: The independent front and rear rotary gain controls are continuously variable from 200 mV to 5 V.

Crossovers: The front and rear crossovers are independent, and not identical:

  • Front: high pass only; 12 dB/octave; crossover point continuously variable from 10 Hz (full range) to 200 Hz
  • Rear: switchable: low pass, full range or high pass; 12 dB/octave; crossover point continuously variable from 50 Hz to 750 Hz

Power/Ground/Turn-On: The TD75.4 features screw terminals for power, ground and remote turn-on. The power and ground terminals will accommodate spade connectors up to 0.5" wide, while the Remote turn-on terminal will accept a spade connector up to 0.335" wide.

Warranty Note: MTX will add a year to the standard one year warranty (for a total of two years) when an appropriate StreetWires amplifier wiring kit is used with this amp (4 or 8 gauge). The amplifier includes no fuse, so a 60 amp fuse should be installed in the power wire. The StreetWires kits listed as accessories include a 60 amp fuse; if a wiring kit is used having a different size fuse, it should be replaced with a 60 amp fuse. Both the amp and wiring kit should be purchased on the same order and the usual warranty limitations apply (covers manufacturing defects, must be purchased from an authorized MTX dealer, etc.).

Line Level Input: The signal is input using two pair of stereo RCA inputs, front and rear.

Speaker Connections: The amplifier is equipped with four pair of speaker terminals, they are screw terminals and will accommodate spade connectors up to 0.325" wide.


5 Year Warranty Terms: This product carries a 5-Year Prorated Warranty with the following terms:

  • Years 1-2: Products found to be defective in materials or workmanship during the first two years will be, at Mitek's option, repaired or replaced by Mitek at no charge. The warranty period does not renew, but continues on from the original date of purchase.
  • Years 3-5: The purchase price of an item which becomes defective after the first two years and prior to the end of the warranty period will be prorated and credited toward the purchase of a new MTX product. The amount of proration is determined by dividing the original purchase price by the number of months in the warranty period (60), then multiplying the result by the number of months remaining in the warranty period.

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.