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Harmony Audio HA-ML181 Monolith 18" Car Stereo Competition SPL Sub 3500W Dual 1 Ohm Subwoofer

  • Based on 16 reviews
Condition: New
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Availability: In Stock.
Fulfilled by HiFi-Soundconnection

Arrives Wednesday, Apr 29
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Size: 1 Ohm


Style: Single Pack


Features

  • HIGH-QUALITY CONSTRUCTION: Crafted with premium materials, the subwoofer's cone is designed for rigidity and minimal distortion, even under intense use. The robust construction ensures durability, making it capable of handling the challenges of competition-grade setups.
  • 3500W PEAK POWER HANDLING: With an impressive peak power handling of 3500 watts, the Monolith 18" Competition Subwoofer delivers exceptional and authoritative bass, making it suitable for enthusiasts who crave high-performance audio experiences.
  • DUAL 1-OHM IMPEDANCE: The subwoofer features a dual 1-ohm impedance configuration, providing flexibility in wiring options. This allows users to customize the impedance to match their amplifier setup, ensuring optimal power transfer and performance.
  • VENTED T-YOKE BACK PLATE: Equipped with a vented T-yoke back plate, the subwoofer efficiently dissipates heat generated during heavy use. This feature ensures the subwoofer remains cool under demanding conditions, contributing to its reliability and longevity.
  • ADDITIONAL ITEM SPECS: The product weighs 61.1 pounds and has dimensions of 21.46 x 21.26 x 16.67 inches, featuring speakers with a maximum output power of 1750 Watts.

Brand: Harmony Audio


Speaker Maximum Output Power: 1750 Watts


Frequency Response: 300 Hz


Connectivity Technology: wired


Audio Output Mode: Stereo


Mounting Type: Car Mount


Material: Metal


Model Name: HA ML181


Speaker Type: Subwoofer, Surround Sound


Recommended Uses For Product: For Cars


Compatible Devices: Car, Home Theater


Subwoofer Diameter: 18 Inches


Unit Count: 1 Count


Surround Sound Channel Configuration: 1.0


Color: Monolith - 1 Sub


Product Dimensions: 21.46"D x 21.26"W x 16.67"H


Impedance: 1 Ohms


Is Waterproof: FALSE


Warranty Type: Extended


Control Method: Voice


Wireless Communication Technology: No Wireless Communication Technology


Speaker Size: 18 Inches


Power Source: Corded Electric


Woofer Diameter: 18 Inches


Audio Driver Type: Dynamic Driver


Audio Driver Size: 18 Inches


Subwoofer Connectivity Technology: Wired


Specific Uses For Product: In-car audio systems


UPC: 603167659076


Style: Single Pack


Manufacturer: Harmony Audio


Shape: Rectangular Prism


Item Weight: 61.1 pounds


Item model number: HA-ML181


Date First Available: June 20, 2019


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Wednesday, Apr 29

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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Leasing options through Acima may also be available during checkout.

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Top Amazon Reviews


  • Two thumbs up
Size: 1 Ohm Style: Single Pack
Great sound and good quality but beware heavy!
Reviewed in the United States on January 12, 2026 by Matt Sr

  • Read..
Size: 2 Ohm Style: Single Pack
I bought a single 18" and built a box for it and this subwoofer SLAPS. Very well made sub with a big heavy magnet, especially for the price. Running it with an American Bass 2000 watt rms amp with half tilt... it moves air and rattles my eardrums along with everything in the car... F.Y.I: Just make sure to buy a professionally made box or really know what you're doing if you make a box. This was my first box i made and within a couple of weeks this sub started ripping the internals of the box apart (ports) so I needed to go back into the box and use heavy duty caulk to fix everything. Sounds better than ever now. ... show more
Reviewed in the United States on July 11, 2020 by Luke Benjamin Luke Benjamin

  • Amazing value, sledgehammer bass
Size: 2 Ohm Style: Single Pack
Absolutely stunned by this sub. Hits like a semi truck. I'm powering it with the Skar 4600 for plenty of ceiling in terms of power. I would definitely get a big effing amp if you want to run this properly. Make sure you get a quality cabinet built custom for it or know what you're buying. I am blown away at the quality and sound for the price. Would definitely recommend this company to friends. ... show more
Reviewed in the United States on May 18, 2021 by Sam Sam

  • Overall happy with purchase, well built, sounds good
Size: 1 Ohm Style: Single Pack
Subwoofer is built well, nice and heavy . Have two of them running on a taramps bass 5k at 1 ohm. I feel they can take quite a bit more . But the sound is nice , the enclosure I have them in is 13cubic ft ported with 15” diameter octoport.. tuned to around 32 hz . Overall I’m happy with this purchase ... show more
Reviewed in the United States on April 20, 2021 by Kyle Crawford Kyle Crawford

  • nice
Size: 1 Ohm Style: Two Pack
100% the bass is crazy and they hit hard is hell
Reviewed in the United States on September 24, 2020 by Terrance Daniels

  • HA-ML181
Size: 1 Ohm Style: Single Pack
I got my sub a day early, it was double boxed and came with screws. I am impressed with the size of this sub and the quality of its built everything looks solid for the price. I made a sealed box @ 6.25cu' (5.76cu' after displacement) it sounds ok but I'm going to port it after I break it in. I would buy this sub again ... show more
Reviewed in the United States on April 15, 2021 by Howard M.

  • MONSTER subwoofer!!!
Size: 2 Ohm Style: Single Pack
This thing is a BEAST!!! Once I build my enclosure I'll post a video.
Reviewed in the United States on July 6, 2021 by Dustin M Spann Dustin M Spann

  • Excelcer
Size: 1 Ohm Style: Two Pack
Amazing subs Harmony Audio And super nice price to. I would say there underrated rms because they are built so well. I absolutely would recommend these subwoofers. What caught my eye was the position of the large foam surround and the huge 10 inch tensl woven spider. To me that said huge excursion. And sure enough I was right. ... show more
Reviewed in the United States on July 9, 2020 by tjz Johnson tjz Johnson

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