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Harmony Audio

Harmony Audio 12" Competition Subwoofer Dual 1 Ohm 3000W HA-ML121 SPL Sub | 12 inch car stereo bass, high-excursion voice coil motor, deep low-end, hard-hitting slam, ported box ready, monolith series

  • Based on 16 reviews
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Availability: In Stock.
Fulfilled by HiFi-Soundconnection
Arrives Thursday, Aug 20
Order within 1 hour and 50 minutes
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Size: 1 Ohm


Style: Single Pack


Features

  • HIGH-QUALITY CONSTRUCTION: The subwoofer features a robust construction with a focus on durability and performance. The cone is crafted from high-quality materials to ensure rigidity and minimize distortion, even under demanding conditions. The subwoofer is built to withstand the rigors of competition and continuous high-power use.
  • 3000W PEAK POWER HANDLING: The Monolith 12" Competition Subwoofer boasts an impressive peak power handling of 3000 watts, making it capable of delivering thunderous and deep bass notes. This high power rating is ideal for users who crave an immersive and impactful audio experience.
  • DUAL 1 OHM IMPEDANCE: With a dual 1-ohm impedance configuration, this subwoofer provides versatile wiring options. Users can choose from various wiring configurations to match their amplifier setup and achieve the desired impedance for optimal performance.
  • DUAL VOICE COIL DESIGN: The dual voice coil (DVC) design enhances the flexibility of wiring configurations. It allows users to customize the impedance and match the subwoofer to their amplifier's capabilities, providing options for different setups and applications.
  • ADDITIONAL ITEM SPECS: The 12" Monolith Series Car Subwoofer, weighing 50.75 pounds and with dimensions of 16 x 16 x 14 inches, delivers powerful audio performance in a compact and substantial design.

Brand: Harmony Audio


Speaker Maximum Output Power: 3000 watts


Frequency Response: 300 hertz


Connectivity Technology: wired


Audio Output Mode: Stereo


Audio Output Mode: Stereo


Mounting Type: Car Mount


Enclosure Material: Aluminum


Speaker Type: Subwoofer


Antenna Location: car


Subwoofer Diameter: 12 inches


Color: Monolith - 1 Sub


Is Waterproof: FALSE


Warranty Type: Limited


Control Method: Voice


Speaker Size: 12 inches


Woofer Diameter: 12 inches


Controller Type: Voice control


Unit Count: 1 Count


Item Dimensions D x W x H: 15.87"D x 16.04"W x 13.36"H


Connectivity Technology: wired


Wireless Technology: No Wireless Communication Technology


Subwoofer Connectivity Technology: Wired


Connectivity Protocol: HDMI, RCA, USB, XLR, aux, coaxial


Audio Driver Type: Dynamic Driver


Audio Driver Size: 12 inches


Brand: Harmony Audio


Model Number: HA-ML121


Model Name: HA ML121


Number of Items: 1


UPC: 603167659038


Manufacturer: Harmony Audio


Speaker Maximum Output Power: 3000 watts


Frequency Response: 300 hertz


Number of Audio Channels: 1


Impedance: 1 ohm


Compatible Devices: MP3 Player, Smartphone, Tablet


Compatible with Vehicle Type: Car


Power Source: Corded Electric


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Thursday, Aug 20

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

    • Great subwoofer
Size: 1 Ohm Style: Single Pack
Review Image by Jamie munger
Review Image by Jamie munger
I originally ordered one of these 2ohm subs for my wife’s Nissan and I loved it. I ended up buying this 1ohm sub for my truck and I have it wired 2ohm and have the harmony sound box as well. I have an nvx nda104 3k mono block powering this sub and it delivers great sound and hard clean bass. The cone and dust cap are carbon fiber and stitched and rugged. The box and sub weighs over 100 pounds,fyi so if you’re just looking for a basic sub keep moving. This sub is power hungry either feed it the power it needs or don’t waste your time. I broke my sub in at half power for a solid two weeks and it’s been perfect since. I’ve had numerous other top brands and cheap china garbage and this sub is beyond worth the money and makes other top brands look really bad when the price comes to play. Again this is not a beginner or just a small upgrade subwoofer. If you by this sub know it’s 3k watts rms it requires a suitable amp and an amp powering range his sub is gonna draw at least 100 amps and it’s going to require the big 3 upgrade, a second battery and isolator and by all means not a cheap wiring kit. Zero guage is a must. With that said if you don’t plan on all of that don’t buy this sub because you will most definitely over work your amp because it will be starving for power and that will send a clipped signal to your sub it will get hot and it will destroy your sub your amp and if your fuse doesn’t pop it will definitely melt an under sized power wire and probably start a fire. I have close to 3100 watts of clean power going to this sub and it can take more no problem. If you are a bass head this sub destroys a lot of other brands on the market and is worth every penny and is equivalent to the exo line from ct sounds but half the price and all of the power and quality. ... show more
Reviewed in the United States on May 31, 2024 by Jamie munger
    • Dumpers ! Recommended
Size: 1 Ohm Style: Two Pack
Review Image by Jacob Brooks
They sure do dump. Straight dumpers. Do to be knowledge i was only able to hook up one to a 4 channel mono block. And just the one speaker hits so hard . I can here my durango coming from a mile away . I recommend these speakers. Cant wait to hook them both up ! Im impressed. 2400 watt quantum audio . Bridge mono block 4 channels . Running on 2 channel. With a 3rd 750 watt alpine bass. Wakes up the neighbors just fine 😎 ... show more
Reviewed in the United States on March 26, 2022 by Jacob Brooks
    • This thing slaps
Size: 1 Ohm Style: Single Pack
I was very indecisive about this sub because it was not a well known name brand and had no videos or not very many reviews. But I took the chance and this thing is amazing had it about 3-4 months and it hits hard every time needs a lot of air has beefy high temp voice coil with black glue huge motor and nice kinda stiff surround I have it on a 1800watt taramps turned all the way up and it sounds amazing ... show more
Reviewed in the United States on June 22, 2021 by Colby
    • Dual Harmony Audio Monoliths 12d1 Subs
Size: 1 Ohm Style: Two Pack
Review Image by George hughes
Bought two 12d1 monoliths after months of research on them I decided to give them a try!!! OMG!!! So glad I decided to try them they are by far some of the best subs I’ve owned and I have plenty of them… I am not going to name bash anyone but with 100% certainty I would put them up against any sub in its class ! In the correct enclosure these subs are hard to beat , just try me ! I’m really blown away by the monolith subs THEY ARE BUILT LIKE TANKS without a doubt. ... show more
Reviewed in the United States on May 10, 2026 by George hughes
    • There awesome subs well worth the 300$
Size: 1 Ohm Style: Single Pack
I wrote a review a few months ago when I first got one so now is the 6 month update. I love these bad boys!!! They def hit hard has hell in every box I’ve put em in. I’m doing a custom bench in back of my f150 with 4 of these and two hifonics colusses 6000 watt amps. I’m jus waiting on my other sub now and it’s going in. I can’t wait!!! But def worth the money compared to sundown and dc audio. It was a toss up because I heard Skar is good to but I went with these and I’m glad I did. Very sturdy construction good motor nice stiff sub but not to stiff and spider is big so it flexes more than the others. ... show more
Reviewed in the United States on April 4, 2020 by mike j Jones
    • Great bargain!
Size: 1 Ohm Style: Two Pack
These subs are bulletproof and sound great. To the guy that had the basket break, when you make the hole too small and you force the subwoofer in there, of course it's gonna be under pressure and crack at the weakest point. I don't fault the manufacturer for that but the user that put them in too small of a hole It put undue force on those thinner parts of the frame at the upper part of the basket... ... show more
Reviewed in the United States on December 12, 2022 by ndtforlife

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