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MTX re-Q5

5-channel bass restoration signal processor
Get full bass response when adding amps to a factory system

4 Reviews

Item # 236REQ5

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Our take on the MTX re-Q5

Most factory stereos, even premium systems, protect speakers by reducing bass output when the volume is turned up. This limitation works great in a stock system, but it'll hamper low-frequency performance if you upgrade your factory stereo with amplifiers and subwoofers. MTX solves this problem with the re-Q5 signal processor.

Most factory stereos, even premium systems, protect speakers by reducing bass output when the volume is turned up. This limitation works great in a stock system, but it'll hamper low-frequency performance if you upgrade your factory stereo with amplifiers and subwoofers. MTX solves this problem with the re-Q5 signal processor.

The re-Q5 senses the input level from the factory stereo, adding more bass at high volume levels and keeping bass response balanced when the volume is low. You'll enjoy full, even bass response at all volume levels. Now you can keep your factory stereo and its steering wheel controls while truly improving your system's sound.

The re-Q hooks up to the speaker outputs of your factory stereo, and includes front, rear, and subwoofer preamp outputs for connection to your amplifiers. You'll find individual gain controls for all the outputs, plus low-pass and subsonic filters for maximizing your sub's performance. A bass enhancement switch lets you kick in a little more bump if you desire.

Another bonus — the re-Q5 includes an auxiliary input, so you can tie an outboard sound source into your factory system and control its level. The auxiliary input module comes with a 16.5-foot cable so you can mount it in a convenient location.

Product Highlights:

  • signal processor restores bass when adding amps to a factory system
  • front , rear, and mono subwoofer preamp outputs
  • variable low-pass (40-200 Hz) and subsonic (10-40 Hz) filters
  • Bass Enhance switch
  • auxiliary input module with 16-1/2" cable
  • processor dimensions: 10-1/2"W x 1-1/2"H x 4-1/2"D
  • warranty: 1 year
  • Our 60-day money-back guarantee

What's in the Box:

  • re-Q5 module
  • Auxiliary module
  • 13.5" Input harness
  • In-line fuse and fuse holder
  • 16.5' Connection cable for auxiliary module
  • 4 Mounting screws
  • Instruction sheet

MTX re-Q5 Reviews

Average Customer Review(s):

(4 Reviews)

It works

Anonymous from nevada on 11/6/2011

Crutchfield Customer Review (What's this?)

well the instructions that come with it work but much better off talking to crutchfield support team after some phone calls and them actually having some wiring diagrams for my factory sound system was great help thanks again crutchfield as for the mtx re-q5 it has done the job and has helped my upgraded sound system sound great with my factory system.



re-Q misunderstood

Smitty from Florida on 8/7/2010

The re-Q works... HOWEVER... for many applications you have to know more details about how the re-Q works. Setting up the re-Q based on the single sheet of instructions provided my MTX is vague at best. The re-Q boosts bass frequencies based on the voltage of the input signal. Many DIY installers don't have the proper equipment to measure the input signals accurately. In my case setup was not so simple. The factory radio cuts bass faster than the re-Q boosts it and when setup by the instructions it produces VERY disappointing performance. I used an O-scpoe, an RTA and a true RMS meter with signal generator to see the big picture with my system. I determined the amount of bass cut from the factory unit. I then used a flat signal to determine the boost rate of the re-Q. By matching the units properly I found a sweet spot that produces excelent flat response at mid to high volume. At low volume there is a slight boost in bass that is so subtle that nobody has noticed. In my case only 70% of the factory radio volume range is used by the time the system maxes out (not an issue for me). I don't have people in my truck that blindly crank the volume knob. The smart engage works fine. After installing this unit I have solved issues with re-Q's in four other vehicles. All of those were tuned using only and RTA and a pink noise CD. Before counting this unit out speak to a VERY qualified installer or call MTX. I have heard they are very helpful.



Great Box

Pete from Texas Panhandle on 3/22/2009

Crutchfield Customer Review (What's this?)

A wonderful piece of equipment to install in order to maintain the GM factory radio/receiver/CD player. Installed this puppy in an '04 Z71 along with a Sony 4 channel amp and a Kicker sub woofer amp. The MTX box is amazing. My mirrors vibrate without distortion. Seriously, this thing does what it says it will do. Great support from the MTX folks, too. Had to make a call to them to find out what would be the best way to connect the remote wire.



MTX re-Q5

Gary from Maryland on 9/5/2008

Crutchfield Customer Review (What's this?)

This is a really good unit, and much cheaper than the JL cleansweep! Great value I think. I bought it so I could keep my stock HU and upgrade the speakers. I'm only using it for the subwoofer I installed right now, but I plan on upgrading my door speakers and using it for that too. It really works great for the sub I bought and eliminates the bass drop-off the factory HU creates. Takes a little bit of time to get all the settings exactly where you want them, but that's part of the fun isn't it? Anyway, great unit, great price, and great for pushing my 12" sub in the back!




Hands-on research

Product Research


Overview: The MTX re-Q5 is a 5-channel volume sensing bass restoration device designed to restore bass when adding aftermarket amplifier to a factory audio system. Most OEM systems "roll off" the bass to avoid damaging the speakers at higher volume levels. While this is acceptable when using stock speakers, it's not desired when adding amplifiers as it limits the low frequency output of your system. The MTX re-Q5 solves this problem by sensing the input from the head unit to add more bass at high volume levels and balances the bass response at lower volume levels. You get the bass you want with added performance while keeping your factory radio and your steering wheel controls.

Balance Bass Enhancement: Rather than just turning up the bass linearly, the re-Q5 senses the factory radio output and adjusts its boost level to balance the sound of all 5-channels in your system (Right Front, Left Front, Right Rear, Left Rear, and Sub). You can select for the re-Q5 to perform its Balance Bass Enhancement after or before the factory amplifier.

Smart Engage: An input signal sensing circuit turns the re-Q5 on automatically. There is also a remote turn-on input if you prefer not to use the Smart Engage feature.

Speaker Level Input: There are speaker level inputs for the Front Left/Right, Rear Left/Right and Subwoofer channels. The compatible input range is 250 mV to 30 V. If your factory system has no sub, the re-Q5's sub output is taken from the left and right inputs.

Line Level Output: The line outputs for Front left/right, Rear Left/Right and Sub are individually adjustable. The maximum output is 2.5 volts for the full range channels and 8 volts for the sub.

Crossover: The subwoofer channel's crossover is continuously adjustable from 40 Hz to 200 Hz.

Subsonic Filter: The subsonic filter is continuously adjustable from 10 Hz to 40 Hz.

Front/Rear Sub Level: In some applications it may be necessary to reduce the low frequency output of the full range outputs on the re-Q5 when summing a factor subwoofer signal with full range signal. This is due to variances in the input signal which are inherent to some factory audio systems. After the re-Q5 is connected, if the low frequency output of the front or rear speakers is too high regardless of gain settings, you can adjust the settings on the Sub Level Front and Sub Level Rear switches to -3dB or -6dB. This will reduce the low frequency output on the front and rear full range outputs.

Auxiliary Module: The MTX re-Q5 comes supplied with a wired Auxiliary module and a 16.5' connection cable. The Auxiliary module features a 3.5mm input jack for connecting an external audio source. The supplied 16.5' connection cable and integrated mounting flanges on the module allow you to mount the Auxiliary interface in the front of your vehicle. The Auxiliary module features its own on/off-volume control knob. The Auxiliary interface measures 3.155" wide x 0.905" tall x 2.015" deep.

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.