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BOSS Audio Systems OX4KD Onyx Series Car Audio Subwoofer Amplifier – 4000 High Output, Class D, 1 Ohm Stable, Low Level Inputs, Low Pass Crossover, Low Pass Crossover, MOSFET Power, Monoblock, Stereo

  • Based on 543 reviews
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Availability: In Stock.
Fulfilled by Amazon

Arrives Thursday, Jun 5
Order within 19 hours and 32 minutes
Available payment plans shown during checkout

Style: 4000W Monoblock


Features

  • Power - 4000 Max x 1 @1-Ohm, 2000 Max x 1 @2-Ohms
  • Class D - Power loss is significantly reduced making the amplifier highly efficient. Excess energy is stored until its needed instead of being converted into heat. Reduction in size/weight, reduced power waste, smaller heat sink, compact circuitry
  • 1 Ohm Stable - Able to continuously power loads of 1 Ohm without encountering difficulties such as overheating. Typically made to power up subwoofers that demand the heavier power load requirements to be able to perform the way they were made to
  • Strapping Capable - You are able to strap two OX4KD amplifiers and double the power that is being sent to your subwoofer(s). You now have the ability to connect more subwoofers to take advantage of the extra power
  • Variable Bass Boost - Bass Boost allows you to adjust the low bass within the boost range to just the way you like it
  • Variable Subsonic Filter - To prevent your subwoofer(s) from bottoming out, the variable subsonic filter filters out frequencies below the subwoofer(s) specified low frequency limits and allows the driver to reach a maximum safe excursion
  • Variable Low-Pass Crossover - Subwoofers reproduce sound based on a number of different low-range frequencies. You can set exact sound specifications for the bass frequency reproduction
  • Specs - Dimensions: 14.3 x 7 x 2.3, Weight: 7.8 lbs.

Item dimensions L x W x H: 14.3 x 7 x 2.3 inches


Voltage: 12 Volts (DC)


Manufacturer: BOSS Audio Systems


Maximum Supply Voltage: 12 Volts (DC)


Mounting Type: Surface Mount


Item dimensions L x W x H: 14.3 x 7 x 2.3 inches


Voltage: 12 Volts (DC)


Manufacturer: BOSS Audio Systems


Maximum Supply Voltage: 12 Volts (DC)


Mounting Type: Surface Mount


Brand: BOSS Audio Systems


Number of Channels: 1


Output Power: 4E+3 Watts


Package Type: box


Specification Met: Electronic_component_amplifier


Material: MOSFET


Global Trade Identification Number: 02


UPC: 791489125802


Product Dimensions: 14.3 x 7 x 2.3 inches


Item Weight: 8.14 pounds


Item model number: OX4KD


Other display features: Wireless


Country of Origin: China


Date First Available: February 26, 2019


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Thursday, Jun 5

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • Pushing 2 15's no problem
Style: 4000W Monoblock
Gotta say I'm impressed with this amp. I upgraded from a Boss 1500w due to my rca inputs going out, typical since the amp was 8yrs old and I put it through hell in those 8yrs. But this 4000w amp is legit, definitely worth the money. It's pushing my 2 15 Skars just fine, got them wired at 2ohms right now. Gonna drop it down to 1ohm and see how it's hitting. Very impressed and would recommend. ... show more
Reviewed in the United States on November 8, 2024 by Jason G.

  • Excellent sound
Installed in a motorcycle, the LED logo lights up blue and looks great. Sounds great as long as your speakers are the correct RMS rating.
Reviewed in the United States on January 1, 2024 by C. Blankenship

  • Strong amp
Style: 3000W Monoblock
Pushes hard but it's higher bass levels & not lower ones
Reviewed in the United States on May 14, 2023 by Richard Owens

  • Worst amp known to man kind
Style: 1500W Monoblock
If you want a low quality, non performing, amp buy this. If it says 1500 watts the most you will receive is 130 watts max output. Save your time and money and buy a Stinger 1500 watts rms.
Reviewed in the United States on September 1, 2024 by Simon

  • Great
Style: 1500W Monoblock
Works well
Reviewed in the United States on January 4, 2024 by margarita hernandez

  • Good price for this amp
Style: 1600 W 4-Channel
I used this amp to power 2 10’s 1100w subs connected to one terminal and 2 800w 6x9 and 2 400w 6.5 they slap! Only problem is when turning up the gain on the subs would go into protect for no reason but I managed to keep it low and have good bass. It sometimes overheats but I don’t mind it.
Reviewed in the United States on March 19, 2021 by Jorge G.

  • Worth the money
Style: 1600 W 4-Channel
Definitely exceeded my expectation. Thought my other amp was messing up so I ordered this. Got it wired in and it definitely has the power and sound quality.
Reviewed in the United States on July 6, 2021 by Georgia Man

  • mine made a pop sound and quit working i was not even using it hard or much
Style: 3000W Monoblock
really cheap and good amp but mine broke. I actually still recommend it
Reviewed in the United States on December 1, 2023 by Nate Foster

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