FOR HELP CALL 877-271-9355

KUBE 12b Subwoofer

Discover sound’s hidden depths with KEF Kube subwoofers. The Kube unleashes explosive power intelligently thanks to iBX technology that extends bass depth dynamically. Delivering immersive music and home theatre sounds that drive you deeper into the heart of the performance.

The Kube 12b features a 12" bass driver powered by a 300 watt RMS bespoke class D amplifier and 3 custom EQ settings for easy placement.

Availability: In stock


Shop the BEST gifts for DAD from KEF


KEF June Specials!  KEF Direct

Explore new dimensions in sound with Kube, KEF’s powerful range of subwoofers that open up sound’s hidden depths.

Each elegantly designed, fully sealed unit unleashes explosive power effortlessly, intuitively, intelligently. iBX technology extends the bass depth dynamically, unlocking the full potential of the driver’s power at normal listening levels or even the most extreme. And with KEF’s unique capability to design, build and integrate the driver in-house, we take optimisation to a whole new level. Delivering immersive music and home theatre sounds that drive you deeper into the heart of the performance.
KEF KUBE Subwoofer Line
KEF Kube Subwoofer FrontImmersiveness

Go deep or go home. KEF’s design and engineering team worked in chorus to develop iBX. This Intelligent Bass Extension algorithm creates an extended depth that unlocks the full potential of the custom driver. Giving you unparalleled precision and ultimate synchronicity between amplifier, driver and sealed cabinet.
Easy configuration

Your room, your rules. Kube subwoofers offer unmatched flexibility in configuration. With a range of LFE, line & speaker-level inputs, Phase selection and 3 DSP controlled EQ settings to help match your sub to any room placement, you’re in control right out of the box. Set up the Kube where it’s most convenient to you, match it to any main speaker or with any type of music system and start exploring new depths in your sound.
KEF KUBE Subwoofer Control Panel
KEF Kube Subwoofer IntegrationIntegration

We’re on the same page. KEF is quite possibly the only high-end manufacturer who designs, engineers and assembles the driver, cabinet and circuitry in-house. This level of integration is the hallmark of our commitment to pure sound and the Kube stays true to that ideal. What you get is a driver and amplifier so perfectly attuned they sing in absolute harmony.

• 56bit 50 MIPS DSP preamplifier
• iBX Intelligent Bass Extension
• KEF smartConnect intelligent inputs automatically detect mono or stereo and adjust the subwoofer volume level accordingly
• Sealed for greater accuracy and delicate musical detail while allowing the Kube subwoofers to be installed in a cabinet
• Placement tuning presets for: Free standing, Wall/in-cabinet and Corner
• 300Watt Class D amplifier with DSP preamplifier/EQ

Customer Reviews

Best bang for buck subwoofer on the market Review by Arthur
Build Quality
Sound Quality
Would you recommend?
If you're looking at KEF then you're probably seeking a certain type of sound quality. You're looking for responsive and tight audio that scales with volume and sounds cleaner than a space satellite construction room. My one concern going into this was that for the $500-$700 range, you wouldn't find a tight and powerful subwoofer as you only start to experience that in the $1200+ range. KEF has surprised me here! The subwoofer remains clean and tight throughout the range without any one frequency droning louder. It has sleek looks to match the quality bass sound.

I do wish there was a phase dial rather than a 0-180 switch but that's a small concern and shouldn't affect those with ample placement options. I have 2 places that I can put the sub so the sweet spot is off by a few feet but it's not a big deal because it still sounds great. The only reason I am giving this subwoofer a 4/5 for sound quality is because I have heard KEF's Reference 8b subwoofer and wish this sounded a bit more like that. The build quality and value for dollar is excellent though which is why my recommendation is 5/5.

I went to this from an SVS SB-2000 and think this sounds miles better.

Cheers and happy listening! (Posted on 1/12/2018)
Fantastic Review by Peter Hyatt
Build Quality
Sound Quality
Would you recommend?
I added this subwoofer to the KEF LS50 W series. Although the LS50W doesn't need a subwoofer, adding it has made a great sound even more enhanced. The sound is rich, deep, but it is very clean. It balances very nicely and is controlled by the KEF app. It is the type of sound that once you experience it, you cannot go back and listen to music without it. Well made, it lives up to the KEF reputation. (Posted on 11/22/2017)


Write Your Own Review

You're reviewing: KUBE 12b Subwoofer

How do you rate this product? *

Model Kube12b Subwoofer
DESIGN Powered Subwoofer
DRIVE UNITS 1 x 300mm (12in.)
FREQUENCY RANGE 22Hz - 140Hz (±3dB)
ANALOGUE INPUT RCA phono sockets
Speaker level inputs
POWER REQUIREMENTS 100V - 120V / 220V - 240V ~ 50 / 60Hz
DIMENSIONS (with Rear panel and feet / H x W x D)
410 x 393 x 410mm (16.1 x 15.5 x 16.1in.)
WEIGHT 20.6kg
** KEF reserves the right, in line with continuing research and development, to amend or change specifications. E&OE. **
KEF KUBE12b Subwoofer Review from AVS Froum KUBE12b Subwoofer - AVS Forum Review & AVS 2018 Top Choice Award
 "In the past, KEF may not have been on your radar when it comes to affordable high-performance subs. But competition among subwoofer makers is fierce and now things are different. For delivering something close to the ideal “living room sub” at its size and price point, I’m giving the KEF Kube 12b a well-deserved AVS Forum “Top Choice 2018” award.”
Year: 2018
Magazine / Issuing Body:
Country: United States
Product: KEF KUBE12b Subwoofer
Read full review.
KEF KUBE12b Subwoofer Review from AVS Froum
KEF KUBE12b Subwoofer Review from Hi-Def KUBE12b Subwoofer - Hi-Def Digest Review
 "Outside of the budget-busting (for me, at least) $1700 R400b, I've never been a huge fan of KEF's more affordable subwoofers, but that all changes with the KUBE 12b. Powered by a 300w Class D amp and custom circuitry, the 12b punches above its class and capabilities, producing deep, buttery bass perfect for those who love to FEEL music and movies.”
Year: 2018
Magazine / Issuing Body: High-Def Digest
Country: United States
Product: KEF KUBE12b Subwoofer
Read full review.
You may also be interested in the following products

Subscribe to our newsletter

Subscribe to our newsletter to receive news, updates, free stuff and new releases by email.