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Harmony Audio 18" Competition SPL Subwoofer Dual 1 Ohm 2-Pack HA-ML181

Based on 24 reviews
Condition: New
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$724.99

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Availability: In Stock.
Fulfilled by HiFi-Soundconnection

Arrives Tuesday, Nov 17
Order within 18 hours and 36 minutes

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At a glance

Condition
New
Size
1 Ohm
Style
Two Pack
Model
HA-ML181x2
Color
Monolith - 2 Subs
Frequency Response
300 hertz
Audio Output Mode
Mono
Works with
Laptop, Desktop, Television, [Smartphone, Tablet, MP3 Player]

Features 4

  • IMPRESSIVE PEAK POWER: Boasting an impressive peak power handling capability of 3500 watts, the Monolith 18" Competition Subwoofer stands out for its ability to deliver exceptional and commanding bass. This makes it an ideal choice for audio enthusiasts seeking high-performance experiences.
  • TAILORABLE IMPEDANCE: With a dual 1-ohm impedance configuration, the subwoofer allows users to tailor the impedance to their specific amplifier setup. This customization ensures efficient power transfer and optimal performance.
  • OPTIMIZED HEAT DISSIPATION: The subwoofer is equipped with a vented T-yoke back plate for optimized heat dissipation during heavy usage. This design choice helps in keeping the subwoofer cool under demanding conditions, contributing to its overall reliability and extended lifespan.
  • ADDITIONAL ITEM SPECS: The 18" Monolith Series Car Subwoofer pair, with a combined weight of 122.5 pounds and product dimensions measuring 22 x 22 x 17 inches, delivers powerful and immersive audio experiences in a substantial yet compact design.

Description

Why do all Harmony Audio subs feature interwoven tinsel leads? The answer is simple we demand nothing but the best. A tinsel lead is a small wire that connects the voice coil to the input terminal and if you look at most other subs its positioned so when the subwoofer is playing the cone will actually slap into the leads creating a pop noise when playing. The advantage to an interwoven tinsel leads is both increased durability and performance which is what Harmony Audio is all about. The greatest enemy of a car audio subwoofer is heat which needs to be quickly dissipated for a sub perform correctly and is crucial to prolong the life of the subwoofer. Harmony Audio Rhythm, Alloy, Carbon & Monolith series subs feature large slotted vents directly under the spider which allows cool air to quickly reach all the sensitive components. The Flatline series features a unique fin-shaped heatsink that transfers heat away from the voice coil. Cutting corners is not the Harmony Audio way and while other manufacturers may be cutting out features to save a penny we are focused on producing a superior performing subwoofer. Take the wire terminal for instance probably one of the most important features of the sub which is what handles the power transfer from your amp to the sub. Many other brands now use a cheap spade terminal that takes longer to install and who knows if it will even stay connected once installed. All Harmony Audio subs feature a spring-loaded push terminal that will accept direct speaker wire ensuring the ultimate connection and power transfer.

Specs 35

Brand Harmony Audio
Speaker Maximum Output Power 7000 watts
Frequency Response 300 hertz
Connectivity Technology wired
Audio Output Mode Mono
Mounting Type Car Mount
Speaker Type Subwoofer, Surround Sound
Additional Features Durable

Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Tuesday, Nov 17

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


Quality built
Size: 1 Ohm Style: Two Pack
Solid construction and build quality. Currently breaking them in at low-med volume 1.5 -2 hrs a day during my commute to work. They are definitely punchy and get low 🤙🏽
Reviewed in the United States on April 27, 2026 by Rabon Lucas

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

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.

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

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

I want another HA-ML181
Size: 1 Ohm Style: Single Pack
🌟🌟🌟🌟🌟 I love my 181 HA sub this thing is massive and it sounds so good in the back of my Cadillac. I’m getting ready to make a blow through. The ski hatch is gonna be the port.. 4th # order blow through with this 18 on smart 5K BASS I'm sure I'll be in the 150+Dbz
Reviewed in the United States on August 17, 2025 by Bass Dezz

Super underrated
Size: 1 Ohm Style: Single Pack
These subs are super underrated i have them on an 8k watt amp and they're laughing at the power. Me that throw each one on per 8k.
Reviewed in the United States on August 8, 2022 by Bryan Somerville
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