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MB Quart ONX4.125

1000W RMS ONYX Series 4-Channel Amplifier (ONX-4.125)

MB Quart
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ONYX Series 4-Channel Class A/B Car Amplifier • 250W x 4 Chan @ 2 Ohm • 125W x 4 Chan @ 4 Ohm • Unbalanced RCA Input Jack • Preamp RCA Outputs • 4-Way System Protection Circuitry • Piano Black Gloss Finish

Learn more about the onx4125

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This item has been discontinued


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Product Highlights


ONYX Series 4-Channel Class A/B Car Amplifier • 250W x 4 Chan @ 2 Ohm • 125W x 4 Chan @ 4 Ohm • Unbalanced RCA Input Jack • Preamp RCA Outputs • 4-Way System Protection Circuitry • Piano Black Gloss Finish

Description


MB Quart brand icon

Authorized dealer

Success is a Measurement of Quality and Power

The success of any car audio amplifier depends on system quality and construction, ease of installation and configuration, and sound enhancing features. MB Quart engineers built the all new Onyx series amplifiers from the ground up to be an affordable amplifier with the audiophile and performance enthusiast in mind. This series is composed of value-packed class A/B amplifiers that boast affordability without sacrifice to power or quality. All Onyx Amplifiers come clothed in a beautiful new age piano black finish which accents interiors and brings a whole new level of sophistication to swallow. To match, the line of Onyx Speakers shows off the same piano black finish applied to their polypropylene cone woofers. It’s a perfect match every time.

Speaking of features, Onyx amplifiers bring the full tuning spectrum to your fingertips with variable high-pass, low-pass and subsonic filters built-in. To increase endurance, MB Quart designed Onyx amplifiers with military grade printed circuit boards and built-in system diagnostics that keep these amps running strong. High speed MOSFET output devices are used in the power supply to give you the best watts-per-dollar ratio. It’s not hard to see how success has been written all over these amplifiers, though with a piano finish that looks that good, we know you will be staring.

  • ONYX Series 4-Channel Class A/B Car Amplifier
  • RMS Power Rating:
    • 4 ohm: 125 watts x 4 chan.
    • 2 ohm: 250 watts x 4 chan.
    • Bridged, 4 ohm: 500 watts x 2 chan.
  • CEA-2006 compliant amplifier
  • Peak Power Handling: 2000 Watts
  • PWM (Pulse Width Modulated) MOSFET power supply
  • LED power (green) and protect (red) indicators
  • Variable Bass Boost (0 to +12 dB bass boost at 45 Hz
  • 4/3/2 channel operation
  • Unbalanced RCA input jack
  • Preamp RCA outputs to daisy chain multiple amps
  • 4-Way System Protection circuitry (DC, thermal, overload, and speaker short protection)
  • Piano black gloss finish with illuminated logo
  • Heavy duty aluminum alloy convection heatsink for superb heat dissipation
  • Silver-plated RCA level inputs
  • Silver-plated screw terminals
  • Input sensitivity:
    • Low level: 200mV-6V
  • Variable high-pass filter (60-13,000 Hz, 24 dB/octave)
  • Variable low-pass filter (30-250 Hz, 24 dB/octave)
  • Damping factor: >180
  • Frequency response: 10-45,000 Hz
  • Dimensions: 20"L x 9"W x 2-1/2"H
  • 4-gauge power and ground wiring is required for installation. Contact us for information regarding a discount on select amplifier kits when purchased together with this amplifier.
  • Authorized Internet Dealer
  • 1-year Manufacturer's warranty

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Specifications & Details


Power Specifications - Full Range Channels
RMS Power @ 4 ohms
125 watts x 4 channel
RMS Power @ 2 ohms
250 watts x 4 channel
Bridged RMS Power
500 watts x 2 channel
Amplifier Specifications
Amplifier Class
A/B
Number of Channels
4-Channel
Total Peak Power Output
2000 watts
Total RMS Power Output
1000 watts
Maximum Input Gauge Size
4 AWG
Minimum Impedance Unbridged
2 ohm
Minimum Impedance Bridged
4 ohms
THD at Rated RMS Power
0.05%
Speaker Level Inputs
No
Preamp Outputs
1 pair
Built-in Crossover
Low-Pass (LP)
High-Pass (HP)
Full (AP)
High-Pass Crossover Frequency
60 - 13,000 Hz
Low-Pass Crossover Frequency
30 - 250 Hz
Signal-to-Noise Ratio
>92 dB
Channel Separation
>80 dB
Bass Boost
0 - 12 dB
Remote bass/level controller
No
Fuse Rating
40A x 3 
Warranty and Return Policy
Parts Warranty Duration
1 year
Labor Warranty Duration
1 year
Warranty Provider
Manufacturer

Item Details


Manufacturer:

Model Number:

ONX4.125

Weight:

16.00lbs

Internal SKU:

onx4125

Internal Product ID:

27474

Product and How-to Videos


Customer Ratings & Reviews


MB Quart ONX4.125 thumbnail image

5 star
74%
4 star
15%
3 star
0%
2 star
4%
1 star
7%



Durability
4.4
Value
4.6
Features
4.4
Design
4.4
Usability
4.7

Customer Reviews

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AMAZING!!

The other reviews are correct. This amp is awesome and powerful and a steal for the price. I also owned the DSC4125 and I didn't notice as big of a difference as they are but it is a extremely powerful amp.

By Sean on May 18, 2011

47 found this helpful


why discontinue all the good stuff?!!!

I am still using this amp years later without fail, baaaaangin!!

By paul on January 21, 2015

45 found this helpful


Best Voice amp i EVER!!!! HAD

This 4 channel amp give off mad!!! Power, Its the best voice amp i ever had, its Kinda Big, but its well worth it in the end. Does not get hot, it fact i wonder if it ever will because i play it so hard.
Get this amp you wont be disappointed.

By MadGuitar07 on November 23, 2011

41 found this helpful


Surprising

Surprised with the kick for the price. Kinda big, but definitely thinking about purchasing another.

By Dubbin on May 3, 2012

41 found this helpful


Times a changing

I have always considered the old school US amps to be uncomparable in sound. I was wrong the new manufacturing of today's technology far out weighs the past. The amp does the job extremely well, Doesn't get hot and the dynamic headroom is as good or undetectable against my a/d/s of the past that I paid 10 times more than this. Time to upgrade everything. This amp is worth every dollar.

By Ben on June 20, 2011

41 found this helpful


Great!!!!

I connected this amp, never imagined the power and the sound quality you don't even need to adjust amp level too high. I recommend this product you would not regret it having one.

By Robert on November 27, 2012

40 found this helpful


Decent Power Per Dollar

Got this amp despite knowing it is not known for quality, because of the reviews. First, are a few notes. It claims it has three 40 amp fuses. However the picture and amp I got have three 35 amp fuses. The manual also recommends 2 gauge wire, although it will only accept as large as 4 gauge (that's what I ran). Also, the plastic on the housing feels cheap, although it's still functional. I'm only using two channels to power a pair of Hertz HSK 165 speakers. Both are rated at 125w rms so it seemed perfect. They get very loud and are very clear, and together overpower a single Alpine Type-R (on a seperate amp). I have no other full range amps to compare to, but the signal is fairly clear. This amp gets the speakers VERY loud and the gain is still fairly low, and I have yet to hear it clip. I temporarily hooked up another sub to make sure all channels worked and at least at that time they all did. I'd love to hook two Type-R's up to it to hear what it would do to for bass, but the budget has yet to allow it. Overall, it's a good amp for the money, it has a lot of features, but don't expect first rate quality.

By SilveradoZ71 on May 19, 2012

40 found this helpful


Great amp

Installed now for a few days and its really surprised me, very loud.

By kyle on March 22, 2012

40 found this helpful


Defective

Bought this amp to power some Polk db6501's and CDT full range speakers and it was defective. Only channels 3&4 work on this amp when used as a 4 channel setup, however channels 1&2 work if you are using it as a 2 channel setup. Waste of time, energy, money, etc. I do not recommend this amplifier.

By Shane on March 11, 2012

38 found this helpful


Good amp for price

I bought this amp to use for a new set of components I purchased at the same time a few months back and it is pretty rad. This amp is easy to use, had a very sleek and nice design, and is in unbeatable for the price. It pushes what it says and is very efficient. I use it to push a set of Rockford T2 components and some pioneers (temporary) and it does amazing. It has popped a couple tweeters sadly but at least I know it's powerful. Overall I would recommend this to anyone on a budget and looking for some power. I will most likely purchase another for my new rebuild.

By Eric on January 17, 2012

39 found this helpful




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